Neutron

One framework ecosystem across 8 languages, backed by Nucleus — a single database engine with 14 data models. Ship web, mobile, desktop, and AI from one mental model.

Website · Documentation · llms.txt · Contributing

Neutron is a modular, multi-language full-stack framework. Every component is independent and connected by one thing — the PostgreSQL wire protocol that Nucleus speaks. Import only what you need: SQL ships by default, and every other data model is an optional import that strips out at compile time.

Quick start

npm create @neutron-build@latest

Scaffolds a TypeScript app with file-based routing, SSR on Preact, and a typed Nucleus client. Then:

cd my-app && npm run dev

Full guide: neutron.build/docs.

For Python, install the published framework directly:

pip install neutron-framework

The package imports as neutron. See the Python quickstart.

Why Neutron

• 8 languages, one contract. TypeScript, Rust, Go, Python, Elixir, Zig, Julia, and Mojo. The six web-framework SDKs (TypeScript, Rust, Go, Python, Elixir, Zig) implement the same framework contract — RFC 7807 errors, a standard middleware order, GET /health, graceful shutdown — while the code stays idiomatic in each language. A language-agnostic conformance matrix in conformance/ verifies this live: all six booted SDKs pass 12/12 dimensions (Go, Rust, Python, TypeScript, Elixir, Zig — measured 2026-08-22). Julia (scientific computing) and Mojo (ML) are client libraries, not web SDKs.
• 14 data models, one database. Nucleus combines relational and specialty storage: SQL, KV, Vector, TimeSeries, Document, Graph, FTS, Geo, Blob, Streams, Columnar, Datalog, CDC, and PubSub — with a PostgreSQL wire endpoint and model-specific APIs. SQL/client compatibility is bounded by the recorded conformance results. 381,558 lines of Rust, 5,721 declared tests, MVCC + WAL crash recovery.
• Fast. On the TypeScript benchmark harness in typescript/benchmarks/, Neutron beat Next.js on all 8 scenarios in every recorded run (2026-02 to 2026-08) and Astro on 6–8 of 8 depending on the run. Absolute throughput varies several-fold across machines — recorded 8-scenario averages span ~3.3k–28.6k req/s — so run the harness on your own hardware before quoting a number.
• Honest about its limits. docs/RESIDUAL_RISKS.md is a standing register of what is not hardened — cross-model transactions, two index paths that read the whole table, what "formally verified" does and does not mean here — kept separate from the release notes on purpose, with each entry naming the test or measurement behind it.
• Agent-native. Ships llms.txt + llms-full.txt, a first-party MCP server (neutron mcp — 17 Nucleus tools plus search_docs/get_doc), and an AGENTS.md in every scaffolded app — so AI coding agents can build with Neutron from day one.

What's inside

Web & app frameworks

Directory	Language	Description
typescript/	TypeScript	UI framework — SSR, file-based routing, Preact, islands, signals
rust/	Rust	Web framework — Hyper, trie routing, HTTP/1–2 (+HTTP/3 behind the http3 feature), 19 composable crates
go/	Go	Backend framework — generics, OpenAPI 3.1, OAuth2, WebAuthn, jobs
python/	Python	AI app framework — Starlette + Pydantic, RAG, MCP integration
elixir/	Elixir	OTP fault-tolerant backend — Plug + Bandit, channels, presence

Database

Directory	Language	Description
nucleus/	Rust	Multi-model engine — SQL, KV, Vector, TimeSeries, Document, Graph, FTS, Geo, Blob, Streams, Columnar, Datalog, CDC, PubSub
studio/	TypeScript	Visual database manager — all 14 data models in one UI

Clients & libraries

Directory	Language	Description
zig/	Zig	Systems/embedded Nucleus client — comptime-typed queries, fixed-capacity connection pool
julia/	Julia	Scientific-computing client — DataFrames, DiffEq, Flux, CUDA, Makie bridges
mojo/	Mojo	ML library — tensors, quantization, inference (preview; built on Mojo 1.0)

Platforms & tooling

Directory	Language	Description
native/	TypeScript	Mobile — React-compatible components to native iOS/Android views (RN Fabric); Preact on web via compat alias
desktop/	Rust + TS	Desktop apps — Tauri 2.0 + Preact, 12 plugin crates, Nucleus embedded mode (bundle-size targets, not yet measured)
cli/	Go	Universal CLI — neutron new/dev/studio/generate/migrate, plus neutron mcp

Verification

Directory	Language	Description
lean4/	Lean 4	Machine-checked proofs of models of the core algorithms (MVCC, B-tree, WAL, Raft)
quint/	Quint	Bounded model-checking of the distributed protocols (Multi-Raft, resharding, distributed tx)

The ORM

Each language ships an idiomatic Nucleus client. The Nucleus engine's 14 data models are SQL, KV, Vector, TimeSeries, Document, Graph, FTS, Geo, Blob, Streams, Columnar, Datalog, CDC, PubSub — per-SDK model coverage varies and is not collectively certified; each bullet below states its own scope.

• TypeScript — @neutron-build/sql (alpha): Drizzle-shaped schema in code, no codegen, typed CRUD + nested relational reads in one statement (db.query.users.findFirst({ with: { posts: true } })), one readable SQL statement per call, toSQL() everywhere; verified on PostgreSQL 15, 16, 17 and 18 with both postgres and pg drivers (changing a generated column's expression needs 17+; Nucleus not claimed). See its support matrix. Existing Drizzle users keep Drizzle through @neutron-build/data's typed interop wrapper.
• Rust — Typed model handles via NucleusClient
• Go — Typed generics, struct tags
• Python — Pydantic models, async
• Elixir — Postgrex pool, OTP patterns
• Zig — Comptime, zero overhead
• Julia — Multiple dispatch, ecosystem bridges

See studio/ for the visual database manager and llms.txt for an AI-readable reference.

Working on the monorepo

# Rust  (nucleus/, rust/)
cargo build && cargo test

# TypeScript  (typescript/, native/ use pnpm; studio/ uses npm)
pnpm install && pnpm test

# Go  (cli/, go/)
go build ./... && go test ./...

# Python
cd python && pip install -e ".[test]" && pytest

See AGENTS.md for contributor and AI-agent guidance, and CLAUDE.md for the full ecosystem map. Each package directory has its own README.

CI

Path-filtered per directory — a change to rust/ only runs rust.yml, and so on for typescript.yml, nucleus.yml, mojo-validation.yml, cli.yml, and desktop.yml.

License

• MIT — all framework projects (typescript/, rust/, go/, python/, elixir/, zig/, julia/, mojo/, studio/, native/, desktop/, cli/, lean4/, quint/)
• BSL 1.1 — Nucleus database engine (nucleus/), converts to MIT on 2046-01-01