All Startup Ideas

AI Code Reviewer

Build an AI-powered GitHub bot that automatically reviews pull requests, catches bugs, and suggests improvements. Full build guide with AI prompts.

Code reviews are a bottleneck. Senior developers spend hours reviewing PRs, often catching the same issues repeatedly: missing error handling, security vulnerabilities, style inconsistencies. Meanwhile, junior devs wait days for feedback, and bugs slip through when reviewers are rushed or tired.

Built for Developers, Solo Founders.

CodeRabbit publicly reports 10K+ repos on the platform and closed a $16M Series A (TechCrunch, 2024) — category is validated, not invented.

Developer tools market is projected past $13B by 2027 (Gartner); Copilot runs at ~$10/seat and normalized a $10–30/dev price band per tool.

A GitHub bot that automatically reviews every PR using AI. It catches common bugs, security issues, and code smells instantly—before human reviewers even look at the code.

Suggested stack: GitHub App + Octokit, Claude + GPT-4o fallback, Postgres (Neon or Supabase), BullMQ + Redis, Fly.io (Node + TypeScript), Stripe + Next.js dashboard. Weekend scope: about 10 hours.

The Problem

Code reviews are a bottleneck. Senior developers spend hours reviewing PRs, often catching the same issues repeatedly: missing error handling, security vulnerabilities, style…

The Solution

A GitHub bot that automatically reviews every PR using AI. It catches common bugs, security issues, and code smells instantly—before human reviewers even look at the code. Humans…

Market Research

GitHub passed 100M developers in 2023 (Octoverse); the PR review surface is where AI value shows up without changing developer workflow.

Competitive Landscape

CodeRabbit — Current category leader. Deep PR context, language coverage, learning per repo. Pricing angles toward mid-market; free tier exists but gates most value behind Pro.…

Business Model

OSS / Free ($0) — Public repos, unlimited PRs, standard review depth; personal Pro trial on private repos for 14 days

Recommended Tech Stack

GitHub App + Octokit — Install-once GitHub App with pull_request and pull_request_review_comment webhooks. Octokit for scoped API calls; signed webhook validation is…

AI Prompts to Build This

Copy these build prompts into Claude, Cursor, or your AI coding tool. Create a free account to unlock the full research behind them.

  1. 1. Project Setup

    Create a Next.js app for an AI Code Reviewer GitHub App.

The app needs:
- GitHub App OAuth flow for installation
- Webhook endpoint to receive PR events
- Dashboard showing: installed repos, recent reviews, settings
- Landing page explaining the product with "Install" CTA

Use Probot library to simplify GitHub App development.
Set up webhook handling for pull_request.opened and pull_request.synchronize events.

  2. 2. Core Feature

    When a PR webhook is received:

1. Fetch the PR diff using GitHub API
2. For each changed file, send to Claude/GPT-4 with this prompt:
   "Review this code diff. Identify: bugs, security issues, performance problems, and style issues. For each issue, specify the line number and provide a suggested fix."
3. Parse the AI response and create GitHub review comments on specific lines
4. Post a summary comment with overall assessment

Handle rate limits and large PRs by chunking files.

  3. 3. Configuration

    Add per-repo configuration via .ai-reviewer.yml file:

- review_focus: ["security", "performance", "style"] - what to check
- ignore_patterns: ["*.test.js", "vendor/*"] - files to skip
- severity_threshold: "warning" - minimum severity to comment
- auto_approve: false - whether to approve clean PRs

Parse this config on each review and adjust AI prompt accordingly.
Build an AI-powered GitHub bot that… | Weekend MVP