tynix

Roadmap

Status legend: ✅ shipped · 🚧 in progress.

Phases 0–4 shipped in the integrated 0.5.0 toolchain release. Phase 5 hardening is largely shipped; the remaining production-readiness work is tracked under the Production Ready (v1.0) milestone.

Phase 0: Spec First ✅

  • document the language design
  • lock down the core type-system concepts
  • define monorepo package responsibilities

Phase 1: Core ✅

  • parser
  • AST
  • pretty printer
  • type representation
  • subtype and consistency
  • basic inference

Deliverables:

  • .tynix -> .nix
  • tynix check
  • tynix emit

Phase 2: Ambient + Workspace ✅

  • .d.tynix parser
  • workspace declaration discovery
  • import declaration resolution
  • declaration emitter stabilization

Phase 3: Type Puzzle Features ✅

  • conditional types
  • infer
  • higher-kinded type application
  • improved solver diagnostics

Phase 4: Tooling ✅

  • Haskell LSP server
  • VS Code extension
  • Zed extension
  • neovim helper

Phase 5: Hardening 🚧

  • larger fixture corpus ✅
  • golden tests ✅
  • regression suite ✅
  • performance tuning 🚧
  • incremental cache ✅ (LSP analysis cache)

Toward v1.0: Production Ready 🚧

Tracked under the Production Ready (v1.0) milestone, organized as epics:

  • Nix-language parity ✅: attrset patterns with defaults and @ binders, inherit (src), nested and dynamic attribute paths, or defaults, every operator (/, ->, |>, <|, prefix -), <nixpkgs>, ~/ and interpolated paths, string escapes. Compiled output of 4000 sampled nixpkgs files parses to the same AST as the source under nix-instantiate --parse.
  • Span-carrying diagnostics ✅: line:col in the CLI, exact underlines in editors, argument-level call mismatches, field-level record errors
  • Checker soundness ✅: Hindley-Milner let-polymorphism with per-SCC generalization, rigid (skolemized) signatures, row-polymorphic open records, optional fields, AttrsOf dictionaries
  • Gradual adoption of unannotated Nix ✅: soft injected dependencies, literal widening, a typed prelude for every builtin; about 98% of a sample of 800 unannotated nixpkgs files type-check
  • LSP features ✅: scope- and type-aware completion, rich diagnostics with related information, unused-binding and deprecation lints, code actions, signature help, navigation
  • Editor setup and distribution ✅: tynix ide install, tynix doctor, the tynix.dev installer, flake packages, overlay and NixOS / nix-darwin / Home Manager modules
  • CLI output contract and exit codes ✅; watch mode 🚧
  • Release/cross-platform packaging and CI hardening (lint, security scan, coverage) 🚧
  • Property-based, integration, golden, and benchmark tests 🚧

Next: Type System

Planned after v1.0, roughly in priority order:

  • type classes, so that constraint contexts such as Functor f => (already parsed) are enforced
  • flow-sensitive narrowing through guards: isAttrs x, x ? a, x._tag == "some" and x != null refining x inside the branch
  • config-aware typing of NixOS, nix-darwin and Home Manager modules, with option declarations driving the type of config
  • implementing records whose fields carry their own forall (instances of Functor-style dictionaries) in .tynix
  • reporting more than one diagnostic per file
  • kind annotations

Shipping Criteria

  • erased .nix preserves source semantics
  • existing .nix files can be typed with .d.tynix alone
  • hover and diagnostics are practically useful
  • the main type-puzzle examples are expressible