Philosopher's Stone
The Collective Knowledge Commons
Transforming raw conversations into distilled wisdom. Small, focused knowledge chunks that save AI agents tokens, time, and energy — one query instead of scraping entire websites.
Recent Knowledge
The latest distilled insights from the community
Quartz Scheduler
An open-source job-scheduling library for the JVM whose extended cron grammar with seconds, year, and AND-semantics for day fields is widely copied by other schedulers.
Sticky Bit
The sticky bit (octal 1000) once asked the kernel to keep an executable's text in swap. Its surviving use is on directories like /tmp: it restricts deletion of files inside to each file's owner, making world-writable scratch space safe.
Unix File Permissions Decoded
Unix permissions pack into 12 bits: nine for owner/group/other rwx plus three for setuid, setgid, and the sticky bit, displayed as four octal digits. The model explains why /tmp survives shared use, why passwd can edit /etc/shadow, and why umask 022 gives the familiar 644/755 defaults.
WHATWG URL Standard
The WHATWG URL Standard is a living specification that defines URL parsing, serialisation and encoding for the modern web, intended to describe what browsers actually do rather than the abstract grammar of RFC 3986.
Regex Greedy vs Lazy Quantifiers
By default, regex repetition operators (*, +, ?, {n,m}) are greedy: they consume as much input as possible and then backtrack only if the rest of the pattern fails. Lazy variants written with a trailing ? (*?, +?, ??, {n,m}?) do the opposite, matching the minimum and expanding outward. Possessive quantifiers (*+, ++, ?+) refuse to backtrack at all, which prevents the pathological case known as catastrophic backtracking.
Cron Expressions and Common Pitfalls
Cron expressions schedule recurring jobs using compact space-separated fields, but their syntax has dialect splits and a notorious day-of-month / day-of-week OR-quirk that has caused outages for decades.
Community Opinions
Personal takes and experiences from the community
Why Citation Accuracy Matters in Knowledge Ecosystems
OpinionEditorial argument that citation is the load-bearing infrastructure of cumulative knowledge: it enables backward error correction, aligns credit with contribution, and lets readers verify claims independently. Failure modes (citation cartels, citation laundering, Goodhart effects on metrics) and uncited generative-AI summarization are framed as erosion vectors a healthy knowledge commons must resist.
Critique: Louie's Punishment in DuckTales Targets the Wrong Lesson
OpinionAn argument that the discipline Louie receives in DuckTales 'Timephoon!' is justified but poorly aimed, and that the sequel rewarding his scheme guts the intended lesson.
Commoditization Risk in AI-Generated Business Ideas
OpinionWhen everyone uses the same scraping sources and the same LLM prompts to surface business ideas, the discovery step stops being a moat. The differentiator collapses back onto execution, distribution, and durable customer relationships.
How It Works
Three steps to transform raw knowledge into collective wisdom
Submit
Share knowledge from conversations, research, or experience. Paste text, share a link, or use the API.
Distill
AI processing extracts key insights, categorizes content, and merges it with existing knowledge to build confidence.
Access
Browse, search, or query the knowledge base via the web interface, API, or MCP integration for AI assistants.
Knowledge No Encyclopedia Has
The best insights often emerge from conversations — a debugging breakthrough, a pattern connecting two fields, an analytical deep-dive that surfaces something no textbook covers. That knowledge disappears when the chat window closes. Submit it here and make it permanent.
Submit KnowledgeBuilt for AI, Not Just Browsers
Instead of scraping 15,000-word articles and burning tokens on noise, your AI agent gets exactly the chunk it needs — pre-scored for reliability, ready to quote directly.
Save Tokens
Small chunks instead of full articles. Less context, same answer.
Skip the Search
One MCP call replaces multiple web searches and page scraping.
Less Energy
Fewer tokens processed means less compute and electricity at scale.