Janus Documentation

Read like Python. Ship like systems. Built for AI agents.

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Quick Start

Write your first Janus program in 5 minutes. Install, build, run. → Get started

Why Janus?

What problem does Janus solve, and why it’s different from Rust, Go, Zig, or Python. → Read the manifesto

Profiles

From :script to :sovereign — six capability tiers that grow with your project. → Explore profiles

Fundamentals

Syntax, types, control flow, error handling, generics, and the pipe operator. → Learn the language

Build a CLI Tool

Ship a native binary from a single .jan file. → Tutorial

Network Services

HTTP servers, async I/O, structured concurrency with nurseries and channels. → :service profile

Distributed Actors

Message-passing, actor state, persistent stores, tombstone compaction. → :cluster profile

Embedded & Sovereign

No ambient authority, pledge/unveil, raw pointers, bare-metal targets. → :sovereign profile

Algebraic Effects

Side effects as part of the function contract, not hidden convention. → Tutorial · → Reference

Hinge Package Manager

Content-addressed modules, signed capsule manifests, supply-chain identity by hash. → Architecture · → CLI Reference

ASTDB Architecture

Every declaration gets a stable UUID. Code is a queryable semantic database. → Architecture

Sovereign Supply Chain

Why names lie and hashes don’t. The philosophical case for content identity. → Read

The Manifesto

Why Janus exists — the 15-year journey from frustration to forge. → Read

Rust Is the Control Group

Why hardcore Rust developers should care about Janus without abandoning Rust. → Read

Janus vs Odin vs Zig

Honest three-way comparison. Where each wins, where each loses. → Read

Eight Axes of Provability

Beyond memory safety: authority, effects, termination, value predicates, and more. → Read

Language Reference

Complete syntax, semantics, and type system documentation. → Read

CLI

janus build, janus run, janus fmt, janus test, and more. → Read

Standard Library

std.cli, std.sync, std.net.http, std.compute, std.text, std.crypto, and more. → Browse reference

Release Log

Every release with what landed, what changed, and what’s next. → Browse releases