Axis.

The thesis.

Axis names a different bet from the rest of the syntactic camp. Most catalogue entries target “LLMs” generically and assume the model has enough context and capability to navigate a large surface. Axis targets the smallest practical agents explicitly — the v0.2 spec declares “target authors: 1B, 3B, 7B parameter models with 2K–32K context windows” — and constrains the surface accordingly. Twelve top-level keywords (SHAPE, SOURCE, REALM, FLOW, SAGA, SURFACE, POLICY, SERVICE, MIGRATE, STREAM, FUNC, STORAGE) cover a production backend; the grammar is LL(1) with one token of lookahead and no backtracking; expressions are prefix-only (FILTER id EQ path.id, never id == path.id); the “one operation per binding” principle forbids compound expressions.

Axis is not a better Python. It is the negation of human-centric programming.

The distinctive move is constrained decoding shipped as toolchain output. axis --constrain exports the parser as a state machine in JSON; axis --logit-masks exports a per-state binary mask over the Axis token vocabulary. The implementation in src/editor/constrain.rs enumerates 41 parse states (TopLevel, ShapeBody, FlowBodyField, FilterClause, …) and emits the allowed token set for each. A host harness maps these masks onto an LLM tokeniser at decode time; the model can then only emit syntactically valid Axis. Most agent-targeted languages assume free generation followed by verification; Axis tries to make syntactic invalidity unreachable at generation time. Mog reaches a comparable surface bound from the spec direction (3,200 tokens fits the language); Axis reaches it from the grammar direction and adds the masks.

What it looks like.

SHAPE Todo
  id UUID PK AUTO
  title STRING 200 REQUIRED
  completed BOOL DEFAULT false
SOURCE todos POSTGRES
SHAPE Todo
INDEX completed
REALM api
CAPABILITY read todos
CAPABILITY write todos
FLOW get_todo get /todos/:id
REALM api
LET todo
FETCH todos
FILTER id EQ path.id
OR 404
RETURN 200 todo

Distinctive moves.

• Targeted at 1B/3B/7B-parameter models. The spec names the audience explicitly. Design principles include “context locality: a single endpoint must be fully generatable within 512 Axis tokens (~2K LLM tokens)” and “failure is syntax: unhandled errors, missing auth, unindexed queries are parse or compile errors, not runtime surprises.”
• Twelve constructs cover a production backend. SHAPE (data model), SOURCE (database binding), REALM (permission scope and tenancy), FLOW (HTTP endpoint), SAGA (distributed transaction with compensating steps), SURFACE (API routing and versioning), POLICY (compile-time invariants across flows), SERVICE (external integration), MIGRATE (schema migration), STREAM (WebSocket/SSE), FUNC (pure function), STORAGE (file backend).
• Grammar-aware logit masks shipped as JSON. axis --constrain emits the parser state machine; axis --logit-masks emits a binary mask per state over the Axis token vocabulary. The harness maps these masks onto an LLM tokeniser at decode time. The masks live in src/editor/constrain.rs; the CLI plumbing in src/main.rs writes them as {vocabulary, masks} JSON.
• Two execution modes from one source. The compile pipeline (lex → parse → link → verify → plan → codegen) emits SQL DDL (--sql), an axum server (--rust), TypeScript and Rust client SDKs, OpenAPI 3.0, GraphQL, Kubernetes manifests, migrations, and a generated test suite, each behind its own flag. axis --serve runs lex → parse → verify → serve, interpreting the AST directly through axum + sqlx against Postgres, MySQL, or SQLite (auto-detected from DATABASE_URL). No codegen step on the serve path.
• Prefix operators, one operation per binding. FILTER id EQ path.id puts the operator first; the design principle forbids compound expressions like a + b * c. Every LET binds exactly one operation, removing precedence ambiguity at the syntax level.
• POLICY as compile-time cross-cutting rules. Tenant isolation, capability checks, rate limits, and auth requirements are declared once in a POLICY block and verified across every FLOW at compile time rather than re-asserted per endpoint.

Maturity.

A single initial commit on 24 May 2026 dropped the entire project as a working Rust workspace: compiler front-end (lexer, parser, link, verify, plan), codegen backends for SQL, Rust/axum, WASM stubs, and client SDKs, generators for OpenAPI, TypeScript, GraphQL, Kubernetes manifests, migrations, and test suites, plus a stdio LSP, a VS Code extension, and a 73 KB specification (docs/axis-spec.md v0.2). Cargo metadata reports version = "0.1.0" against Rust 1.85 (edition 2024). The repository ships three working projects: todolist/ (CRUD proof, 20/20 integration tests), advanced/ (auth, tenants, guards, rules, funcs, MATCH, TRY/RECOVER, rate limiting, caching, surfaces — 32/32 tests), and helperbook/ (a client-provider marketplace with Postgres, Redis, Meilisearch, Prometheus, and Grafana wired through Docker Compose, “zero application source code” outside .axis files).

3 stars, 0 forks, 0 open issues at time of cataloguing; no GitHub releases tagged. The repository does not ship a LICENSE file and the GitHub API reports the licence field as null; the Cargo.toml manifest declares license = "MIT", but the absence of a top-level licence file leaves the question open until the author resolves it. The bet is the one named in the spec’s framing sentence (“the negation of human-centric programming”) — that a domain-specific surface drawn tight enough for a 1B model to navigate, plus grammar-aware decoding to keep it on rails, will outperform a general-purpose language plus a frontier model. No catalogue entry has previously shipped grammar-aware logit masks; integration with a downstream decoder is the next milestone to watch for.

Agent tooling.

CLAUDE.md (7.5 KB) targets agents writing the Axis compiler itself, not agents writing in Axis: it names the build commands, maps the repository module by module, names canonical AST field names to head off guessing (“TypeExpr — not FieldType, not ScalarType”), and states the two pipelines explicitly. No AGENTS.md, no SKILL.md, no MCP server, no llms.txt. The surface for authoring Axis is the constrained-decoding pipeline: axis --constrain for the grammar state machine, axis --logit-masks for the per-state vocabulary masks, axis --completions for parser state and valid next tokens at a cursor position, and axis --lsp for editor integration. Compile-mode outputs (--plan, --openapi, --testgen, …) emit structured JSON for downstream agents to consume.