X07

Website | Source

Eliminates text syntax. Programs are canonical JSON ASTs (x07AST); edits are RFC 6902 JSON Patch operations; diagnostics ship as stable JSON with quickfixes the toolchain applies deterministically.

Camp: Syntactic
Author: Author unknown
Implementation language: Rust
Compilation target: Native (via C codegen); WebAssembly
Licence: Apache-2.0 OR MIT
First seen: April 2026
Maturity: working compiler

Agent tooling:
- AGENT.md
- Agent portal at /agent with versioned JSON entrypoints (manifest, schemas, skills, examples, stdlib, packages)
- x07-mcp (build MCP servers in X07)
- x07lang-mcp bridge (typed access to the toolchain over MCP)
- Per-release skills pack
- Stable error codes; quickfixes emitted as JSON Patch

Key idea

X07's canonical source is not text. A program is an x07AST JSON document (*.x07.json) with a versioned schema; edits are RFC 6902 JSON Patch operations the toolchain applies mechanically. The toolchain emits stable error codes as structured JSON, paired with quickfixes the agent can apply with x07 fix --write or x07 ast apply-patch. Side effects live in explicit capability worlds; sandboxing is policy-driven.

Thesis

X07's diagnosis is that text-based source is exactly where agents lose. Whitespace becomes load-bearing, identical ASTs serialise differently, patches collide on formatting noise, and diagnostics are written for humans. The syntactic-camp move is to delete the text layer: the canonical source is *.x07.json (the x07AST), patches are RFC 6902 JSON Patch documents, diagnostics are JSON with stable error codes, and quickfixes are themselves JSON Patches the toolchain applies deterministically via x07 fix --write or x07 ast apply-patch.

One canonical approach. No "should I use a for loop or map?" decisions.

The distinctive move is the breadth of the machine-facing surface around the language. x07lang.org/agent publishes versioned JSON entrypoints — manifest.json, schemas/index.json, skills/index.json, examples/catalog.json, stdlib/index.json, packages/index.json — explicitly so agents consume them directly rather than scraping the HTML. Side effects are gated by named capability worlds (run-os, run-os-sandboxed); the official tooling includes an MCP kit (x07-mcp) for authoring MCP servers in X07 and a separate bridge (x07lang-mcp) for connecting external agents to the toolchain. The closest direction-of-travel is Magpie, which surfaces SSA at the source level; X07 deletes the source level.

What it looks like.

{
  "schema_version": "x07.x07ast@0.4.0",
  "kind": "entry",
  "module_id": "main",
  "imports": ["std.bytes"],
  "decls": [],
  "solve": ["std.bytes.reverse", "input"]
}

A program is a JSON document. A quickfix is an array of JSON Patch operations applied to this document; the agent never edits a string of source code, only the structural tree.

Distinctive moves.

AST as canonical source. The on-disk artefact is the parsed tree, not text. Schemas are versioned (x07.x07ast@0.4.0).
JSON Patch as the edit primitive. Repairs are structural diffs that apply mechanically; whitespace cannot break a patch because there is no whitespace.
Capability worlds for effects. Programs run in deterministic solve worlds or named OS worlds (run-os, run-os-sandboxed); ambient access is not available by default.
Stable diagnostic codes with deterministic quickfixes. x07 lint emits x07diag JSON with a stable code and an optional JSON Patch fix; x07 fix --write applies it.
Versioned agent portal. Each toolchain release ships an /agent/v<version>/ directory of machine entrypoints alongside the human docs.
Performance claims with a published comparison repo. The README points at x07lang/x07-perf-compare (v0.0.3 snapshot) reporting native-code parity with C/Rust on the included workloads and faster compile times; the methodology lives in that separate repository.

Maturity.

The repo (x07lang/x07) is a multi-crate Rust workspace dual-licensed Apache-2.0/MIT with 471 commits and 108 tagged releases (latest GitHub tag v0.1.49, Mar 2026); the documentation site lists further point releases above that as the docs source of truth (latest 0.2.10). The /agent portal advertises 14 skills, 258 schemas, 17 examples, 410 packages, and 19 stdlib modules — a documentation surface larger than most catalogue entries. The observable community signal lags that surface sharply: 7 stars, 0 forks, 0 open issues at time of cataloguing, and the README does not name the author. The bet is that the canonical-artefact-plus-JSON-Patch model attracts agent integrators on its own merits; the gap between the published toolchain depth and the visible user base is the entry's defining quality and worth flagging.

Agent tooling.

AGENT.md at the repo root is the human-readable orientation; everything else is structured. The /agent portal publishes stable JSON entrypoints per-version (entrypoints.json, manifest.json, schemas/index.json, skills/index.json, examples/index.json, stdlib/index.json, packages/index.json). The toolchain ships an MCP kit (x07-mcp) for authoring MCP servers in X07 and a bridge (x07lang-mcp) for connecting agent runtimes to the toolchain itself. The canonical loop is x07 init → x07 lint → x07 fix → x07 run → x07 test, every stage emitting structured JSON.

Design DNA

Magpie (Syntactic) — Same-camp cousin pointing the same way. Magpie surfaces SSA but keeps source text; X07 walks past text and treats the AST itself as the canonical artefact. Same direction, further along the axis.
Sever (Syntactic) — Both push the surface as far from human authoring as the camp allows; Sever crams meaning into single characters, X07 abandons characters as the unit altogether.
NERD (Syntactic) — Opposite end of the same camp. NERD keeps text and economises tokens inside it; X07 declares text a lossy intermediate and edits the tree directly.

Tags: ai language syntactic native web assembly

Last modified 15 June 2026

X07

AI-first programming language that eliminates text syntax in favor of JSON ASTs.