Overview
Oath Language is the v0 kernel of a single question: what would a programming language look like if it were designed only for AI authors — no human ergonomics, no files, no style, just verifiability and locality?
Definitions are content-addressed — a definition's identity is the SHA-256 of its canonical AST. They carry machine-checkable properties as part of their signature, and live in an immutable object database instead of source files. Names are metadata. The kernel refuses ill-typed code at the gate, runs every property with deterministic inputs before a name is trusted, and records an honest guarantee level on every definition.
The positioning, settled after two external reviews: the syntax is disposable, the substrate is the product. The s-expression surface is an input format that elaborates to the canonical AST and is thrown away.
What's real today
- Two independent kernels. A Go reference implementation (zero dependencies) and a Rust kernel built blind from the specification alone. They produce byte-identical hashes and agree on every verdict across six conformance checks.
- A real guarantee system. asserted → tested → PROVEN, with FALSIFIED as a first-class outcome. 134 properties across 56 definitions are proven for all inputs by Z3; 37 definitions are fully proven.
- Four verdict dimensions. Termination (a lexicographic structural checker), confinement (capability escape tracking), spec strength (mutation testing with justified waivers), and provenance (an append-only, tamper-evident journal).
- Honest exhibits kept on purpose. A falsified
bad-reverse, a non-terminatingspin, and anabs-smallthat tests green but is refuted by proof.
The shape of a definition
A definition is an object. Its bytes are the canonical binary encoding of its AST; its hash is its name-independent identity. Around it sits mutable metadata: the human-readable names that point at it, the guarantee verdicts the kernel derived, and the provenance of who put it there. Change the body and you have a different object with a different hash — the old promise is never silently overwritten.
Read on: Quickstart to run the kernel, The guarantee ladder for how much a verdict actually means, or Architecture for how the pieces fit together.