Stop pasting code.
Start prompting with architecture.

Sigil scans your codebase — Next.js, Express, Fastify, React, Drizzle, Prisma, and more — and generates a token-efficient context.yaml giving your AI the deep structural understanding it needs.

Get Started View on GitHub
$ npm i -g @sigil-engine/cli copy copied!
MIT Licensed TypeScript Plugin Architecture

Get Started

1 npm i -g @sigil-engine/cli or: brew tap riomyers/sigil && brew install sigil
2 sigil profile init Set up your AI identity (once, globally)
3 sigil init Extract architecture + inject profile & rules
4 Your AI now has full context + your identity + your rules.
What You Get

See your architecture instantly.

Run sigil show and see every entity, component, route, and pattern in your codebase.

sigil show ~/my-app
$ sigil show

  my-app — Context Summary
  ────────────────────────────────────────
  Extracted: 2026-03-19
  Time: 2929ms
  Plugins: typescript@0.1.0

  Stack
    framework: next.js@16
    orm: drizzle
    database: postgresql
    ui: tailwind, shadcn
    auth: next-auth

  Architecture
    Entities:   31
    Components: 28
    Routes:    20
    Exports:   115

  Entities
    Users  (8 fields)  ← src/db/schema.ts
    Posts  (6 fields)  ← src/db/schema.ts
    Invoices (12 fields) ← src/db/schema.ts
    ...28 more

  Patterns
    auth: next-auth with JWT strategy
    styling: tailwind + CVA variants
    data_fetching: server components
Visualization

Explore the dependency graph.

Run sigil graph to launch an interactive force-directed graph of your entire codebase.

Sigil Graph — Cal.com architecture visualization

Open live demo →  ·  Cal.com: 1,072 components · 67 routes · 1,676 exports · parsed in 5.8s

The Difference

Before & After

What refactoring with AI looks like — without Sigil, and with it.

Without Sigil: The Context Cram

  1. Spend 10 minutes hunting for all relevant files across the project
  2. Copy & paste each file into Claude or ChatGPT, prefixed with file paths
  3. Hit the context window limit — cut half the files and hope for the best
  4. AI hallucinates function names, misunderstands DB relations, ignores conventions
  5. Get code that's 50% correct and 100% untrustworthy
Result: an hour wasted. Back to manual refactoring.

With Sigil: The Architectural Prompt

  1. Run sigil init — 3 seconds, one time
  2. Your AI automatically has the full context.yaml
  3. AI understands every entity, component, route, pattern, and convention
  4. Get system-aware code that respects your architecture and naming
  5. Production-ready implementation, drop-in ready
Result: a working plan in 5 minutes.
How It Works

Four commands. Full cycle.

Define rules, extract architecture, visualize it, track drift — all from the terminal.

Profile

Set up your global AI identity once — how the AI should behave, communicate, and handle your workflow. Applies to every project.

$ sigil profile init

Name: Rio
Role: Senior engineer
Style: concise

Profile saved to ~/.sigil/profile.yaml

Init

One command injects three layers into your AI tool. Run from anywhere — Sigil finds your projects and lets you pick.

$ sigil init

✓ Context extracted
✓ Loaded behavioral profile
✓ Loaded 2 rules
✓ Created CLAUDE.md

Graph

Launch an interactive dependency graph. Click nodes, search, filter by type.

$ sigil graph

⚡ Sigil Graph — my-app
🌐 http://localhost:4040

Nodes: 176 | Edges: 89

Diff

Detect architectural drift. See what changed structurally since the last extraction.

$ sigil diff

+ entity: PaymentMethod (5 fields)
~ component: Dashboard
  + prop: billingEnabled: boolean
- route: /api/legacy-auth
Use Cases

When to use Sigil

Real scenarios where structured context changes everything.

sigil profile + sigil init

AI That Knows You

Set up your identity, communication style, workflow rules, and code standards once. Every AI tool — Claude, Cursor, Copilot — gets the same behavioral context. Stop repeating "be concise" and "run tests first" every session.

sigil graph

Onboard in 15 Minutes

New to a project with hundreds of files? Launch the interactive graph. Click through components, trace dependencies, understand the architecture visually — without reading a single line of code.

sigil diff

Catch Breaks in PRs

Run sigil diff against main. It flags removed database relations, disabled auth on endpoints, and changed component contracts — architectural bugs you'd never catch in a file-by-file code review.

Comparison

Why Sigil?

Existing tools solve pieces of the puzzle. Sigil is the complete picture.

Feature Sigil repomix aider repo-map Cursor Indexing
Structured output YAML/JSON flat text ~ tree-sitter map proprietary
Architecture-aware entities, routes, patterns, call graphs file dump ~ symbols only ~ basic
Interactive graph force-directed
Drift detection structural diff
Auto-configures AI tools 6 tools self only
Behavioral profiles global + local
Custom project rules sigil.config.yaml
Plugin system any language
Open source MIT MIT Apache 2.0 proprietary

Structured YAML/JSON Output

Not a flat text dump — structured architecture with entities, components, routes, and relationships.

repomix: flat text · aider: tree-sitter map · Cursor: proprietary

Interactive Dependency Graph

Force-directed visualization of your entire codebase. Click, search, filter by type.

No other tool offers this.

Architectural Drift Detection

Compare snapshots to see what changed structurally — added entities, modified props, removed routes.

Auto-Configures 6 AI Tools

Claude Code, Cursor, Windsurf, Cline, Copilot, Continue — one command configures all.

Behavioral Profiles

Define your identity, style, and workflow rules globally. Every project, every AI tool.

Plugin Architecture

Supports Next.js, Express, Fastify, Hono, Drizzle, Prisma out of the box. Add any language via plugins.

MIT Licensed & Open Source

Use it everywhere. Embed it in anything. No vendor lock-in.

Development

Recent Activity

Live from the GitHub repository.

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