N3MO — Automated PR Review & Code Impact Analysis Tool

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Automated PR Review — Know What Breaks Before You Push

N3MO is a code review automation tool that parses your repository's ASTs and builds a call graph to trace the transitive blast radius of any pull request change instantly.

Benchmark: Indexed TensorFlow in 14.06 minutes (14,611 files, 79,523 symbols, 480,851 edges)

Affected Files: 3

Transitive Callers: 8

Severity: High Impact

auth_user

POST /login

admin_login

require_auth

Powerful Features for Automated Code Review

Stop guessing what your pull requests will break. N3MO builds a relational knowledge graph of your codebase to empower engineering teams with precise impact analysis.

Traces call links recursively to arbitrary depth, showing you direct and indirect downstream impacts of any refactor or deletion. Find hidden dependencies that standard search tools miss.

Root: auth.py Transitive Depth: 5 DB Resolution: Scope-Aware

SELECT symbol, file_path FROM callers WHERE target = 'db_pool';
> Found 12 matching transitive callers across 4 service layers.

Powered by GitHub's Tree-sitter. We parse Python, TS/JS, Java, Go, Rust, C++, Ruby, PHP, and more locally.

*Tree-sitter parsing supported for 27 languages. Deep semantic call graph mapping currently optimized for Python, JS/TS, and Java.

Python TypeScript Java

Integrate N3MO directly into Cursor, Claude Desktop, or Windsurf. Allow AI agents to trace structures without hallucinations.

Model Context Protocol Active

Enforce codebase size-aware checkpoints on every Pull Request, posting a comprehensive impact markdown report directly to PR comments in under 2 seconds.

◈ N3MO Impact Check: PASSED
• Modifying auth_user affects 3 downstream components.
• Transitive blast radius: High Impact (8 caller nodes).

Who is N3MO Built For?

A concise breakdown of our ideal user profiles.

Staff Engineers

Architects managing large, legacy monoliths who need a reliable way to map sprawling dependencies before initiating major refactors.

Code Reviewers

Senior developers acting as gatekeepers on PRs who want automated, mathematically-proven impact analysis instead of relying entirely on unit tests.

AI Code Agents

Autonomous coding bots like Claude and Cursor that require a precise, deterministic knowledge graph to avoid hallucinating file structures.

How It Works: A Practical Scenario

Step-by-step instructions on catching breaking changes.

01

Install the GitHub Webhook

Navigate to your repository settings and grant N3MO read access to your source code. You don't need to configure CI/CD pipelines or write custom workflows.

02

Open a Pull Request

A junior developer opens a PR modifying a seemingly isolated utility function, `format_date()`. Unbeknownst to them, this function is indirectly used by the core billing service.

03

Review the Impact Report

Within 2 seconds, N3MO intercepts the webhook, parses the entire AST, and posts a comment on the PR detailing the exact downstream services that depend on `format_date()`. You catch the breaking change before it hits production.

Native MCP Server Integration

Give AI agents like Cursor and Claude deterministic structural context instead of random file chunks.

Automatically configure N3MO as an MCP tool for Claude to map blast radius before it writes code.

$ cd /path/to/project
$ n3mo mcp install

Add N3MO directly to Cursor settings to enable instant transitive impact queries during refactoring.

  • Go to Settings -> Models -> MCP
  • Type: command
  • Command: n3mo mcp start

Plans & Pricing

Scale N3MO's PR impact check capabilities dynamically to fit the size of your team's codebases.

No seat-based pricing. Ever.

N3MO prices by repositories, not users, so your entire engineering team can collaborate without buying additional licenses. Each repository receives continuous indexing, dependency analysis, PR impact detection, and code intelligence. Start free with local MCP — upgrade only when you want automated PR checks across your team.

  • Up to 1 repo
  • 30,000 LOC per repo
  • 30,000* max total LOC
  • Real-time PR Impact Analysis
  • Interactive Dependency Graph
  • Community support

Popular

  • Up to 3 repos
  • 100,000 LOC per repo
  • 300,000* max total LOC
  • Everything in Standard Plan
  • Multi-repo dashboard
  • Email & community support
  • Up to 5 repos
  • 200,000 LOC per repo
  • 1,000,000* max total LOC
  • Everything in Pro
  • Slack notifications & RBAC
  • Priority SLA support
  • Up to 7 repos
  • 500,000 LOC per repo
  • 3,500,000* max total LOC
  • Everything in Team Basic
  • Custom webhooks
  • Advanced Org RBAC
  • Unlimited repos
  • Unlimited LOC
  • Everything in Team Pro
  • Self-hosted & Offline JWT
  • SSO/SAML & Audit logs
  • Dedicated Success Engineer

*Fair use applies. Repository limits are intended for typical engineering teams. Extremely large monorepos may count against your codebase quota. Contact us for larger deployments.

Works with

GitHub GitLab Bitbucket

Supports

Python Go Java TypeScript Rust C++ C#

Why repositories instead of seats?

Traditional SaaS N3MO
Pay per developer Pay per repository
More employees = higher bill Unlimited teammates
Seat licenses Repository intelligence
Penalizes team growth Encourages collaboration

Frequently Asked Questions

What counts as a repository?

Any GitHub repository that you connect to N3MO and actively analyze using our webhook integrations.

Can I invite unlimited teammates?

Yes! Once a repository is indexed, anyone on your team can view PR impact reports and use the interactive graph without needing their own license.

What is a monorepo?

A single repository containing multiple distinct projects or services. Monorepo support on the Team plan ensures we index all nested dependencies properly.

What happens if I exceed the limit?

You'll get a heads-up before any repo stops syncing, with a one-click upgrade — no PRs are ever silently blocked without warning.

Local CLI Reference

N3MO is fully functional locally right from your terminal.

1. Installation

Install the N3MO CLI package directly from PyPI.

pip install n3mo

2. Setup Database & Crawler

Spin up N3MO's PostgreSQL docker container and verify local variables in one command.

n3mo setup

3. Index the Workspace

Index AST structures and build the relational call links inside Postgres.

n3mo index

4. Run Impact Queries

Trace the impact chain and launch the orbital interactive visualizer in your local browser. 

n3mo impact "symbol_name" --graph

◈ IMPACT ANALYSIS
──────────────────────────────────────────────────
Target: authenticate_user
──────────────────────────────────────────────────

◉ Direct Callers (3 symbols)
  ▸ login_endpoint            api/auth.py:12
  ▸ refresh_token             api/token.py:23
  ▸ validate_session          middleware/auth.py:89

◎ Ripple Effects (5 symbols)
    ╰─▸ POST /login           routes.py:67
    ╰─▸ admin_login           admin/views.py:34
    ╰─▸ require_auth          decorators.py:12
    ╰─▸ dashboard_view        views/dashboard.py:8
    ╰─▸ settings_view         views/settings.py:22
──────────────────────────────────────────────────
Total impacted: 8 references │ depth ≤ 3

Privacy and Code Governance

We believe code should be analyzed where it lives. N3MO is designed from the ground up to respect security boundaries and data governance rules:

Zero Stored Source Code

For SaaS users, N3MO analyzes code entirely in-memory on highly secure, ephemeral GitHub runners. We extract only the structural graph metadata, and the runner is instantly destroyed. We never store your raw source code.

Zero-Trust Deployments

Enterprise users run the N3MO CLI natively inside their own private, air-gapped CI/CD pipelines. In this mode, your code literally never leaves your Virtual Private Cloud (VPC).