A thinking system, not a note-taking app

Remember why you made
that decision

Six primitives. No folders. No tags. Just structured thinking that compounds over time. Built for engineers who value clarity over flexibility.

Six primitives. That's it.

Technical people don't think in "notes." They think in hypotheses, tests, and outcomes. These six primitives map directly to how engineers actually work.

Assumption

Something you believe but haven't verified

"Redis will handle our read volume at scale"

Experiment

A deliberate test to validate an assumption

"Load test Redis with 10k concurrent reads"

Decision

A choice with context and trade-offs recorded

"We'll use Postgres over MongoDB because..."

Failure

Something that didn't work, with analysis

"The caching layer added latency instead of reducing it"

Conclusion

A validated insight from experiments or failures

"Our bottleneck is network I/O, not database queries"

Question

An open problem you're actively thinking about

"Should we rewrite the auth system or patch it?"

What's intentionally excluded

The constraints are the product.

Tasks / Todos

This is not a project management tool. Use Linear or GitHub Issues.

Meeting notes

Low-signal, high-volume noise. Not thinking.

Bookmarks / Links

Hoarding is not thinking. Extract the insight as a Conclusion.

Daily journals

Encourages volume over clarity. Not supported.

Tags

Leads to over-categorization and maintenance burden. Use full-text search.

Folders / Hierarchy

Forces premature structure. Everything is flat with links.

Built for a specific kind of person

This is for you if...

  • You've abandoned Notion because you spent more time organizing than thinking
  • Tried Obsidian but your "second brain" became a graveyard of orphaned notes
  • Currently using a single markdown file because everything else is too much
  • You value constraints over flexibility
  • You want to remember why you made decisions 6 months ago

This is NOT for you if...

  • You want customization and flexibility
  • You need team collaboration features
  • You want to publish or share your notes
  • You need offline-first functionality
  • You describe yourself as a "PKM enthusiast"

Simple, honest pricing

No free tier bait-and-switch. No dark patterns. Cancel anytime.

Free

Try the mental model

$0/forever
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Up to 50 entries
All 6 entry types
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$6/month
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Priority support

No team plan

And that's intentional

Team features would change:

  • -The product focus
  • -The target user
  • -The simplicity

This is individual memory, not collaboration software. Your thinking is yours.

Full data portability

Export everything in open formats anytime. Your data is yours. No lock-in, no hostage situations.