Core Concepts

Fundamental concepts and primitives in τ

Core Concepts

Understanding τ starts with understanding its four fundamental primitives:

File Structure
Primitives
Tau (τ)
Schedule
Frame
Lens

The Four Primitives

1. Tau (τ)

An immutable delta valid for an explicit time range. Store only what changed, when it changed.

Learn more about Tau →

2. Schedule

An ordered collection of related Taus. Reconstruct any point in time by replaying deltas.

Learn more about Schedule →

3. Frame

A grouping of schedules that belong together. Organize related time-series data with clear boundaries.

Learn more about Frame →

4. Lens

A transformation that acts as both view and migration. Define once, auto-evolve forever.

Learn more about Lens →

Design Philosophy

Immutable by Design

τ is built on the principle that data should never be lost. Every change is recorded as a new Tau, preserving complete history.

Comparison with Traditional Databases

| Feature | Traditional DB | τ (tau) | |---------|---------------|---------| | Updates | Overwrite | Append new Tau | | History | Optional/Complex | Built-in | | Time Queries | Slow/Unsupported | First-class | | Migrations | Downtime required | Zero-copy with Lenses |

Next Steps

  • Start with Tau (τ) - the fundamental unit
  • Learn about Schedules for time-series
  • Explore Frames for data organization
  • Master Lenses for views and migrations

Last updated: 2/1/2026