---
title: Compiler Architecture
description: High-level pipeline overview of the Mist compiler and crate organization.
icon: Building2
---

### Pipeline Overview

The Mist compiler operates in distinct phases:

```
Source (.mist)
    │
    ▼
┌─────────────┐
│   Lexer     │  (pest PEG grammar)
│   & Parser  │
└─────────────┘
    │  AST
    ▼
┌─────────────┐
│  Semantics  │  (field init checking)
└─────────────┘
    │
    ▼
┌─────────────┐
│  Codegen    │  (AST → Rust source)
└─────────────┘
    │  .rs + .map.json
    ▼
┌─────────────┐
│    cargo    │  (Rust compilation)
└─────────────┘
    │
    ▼
  Binary / Library
```

### Crate Organization

The compiler is written in Rust and Mist itself, organized into four main crates:

| Crate | Language | Role |
|-------|----------|------|
| **mist-parser** | Rust | PEG parsing via pest, AST construction, semantic checks, position mapping |
| **mist-codegen** | Rust | AST → Rust source code generation |
| **mist-analyzer** | Rust | Language server bridging mist-editor ↔ rust-analyzer |
| **mist-api** | Mist | Orchestrates transpilation, module tree building, cargo invocation, error remapping |