Code Roast Bot

An AI-powered code analysis tool built with Next.js and Google Gemini. Paste your code, choose a mode, and get structured feedback on bugs, security issues, complexity, and refactoring opportunities.

Features

• Three analysis modes
  • Strict Review — identifies bugs, security vulnerabilities, and anti-patterns
  • Optimize — reports time and space complexity with improvement suggestions
  • Refactor — rewrites the code for cleaner structure
• Five supported languages — JavaScript, TypeScript, Python, Java, C++
• Monaco Editor — syntax-highlighted input and refactored output
• Structured output — all results rendered from validated JSON fields; no raw LLM text displayed
• 500-line input limit — enforced server-side before the LLM is called
• Rate limiting — configurable per-IP request throttling

Tech Stack

Layer	Technology
Framework	Next.js 16 (App Router)
Language	TypeScript
LLM	Google Gemini (@google/genai)
Validation	Zod
Editor	Monaco Editor
Styling	Tailwind CSS v4

Getting Started

1. Clone and install

git clone https://github.com/your-username/code-roast-bot.git
cd code-roast-bot
npm install

2. Configure environment variables

Create a .env.local file in the project root:

# Required
LLM_API_KEY=your_google_gemini_api_key

# Optional — defaults shown
LLM_MODEL=gemini-2.5-flash
RATE_LIMIT_MAX=10
RATE_LIMIT_WINDOW_MS=60000
GLOBAL_REQUEST_LIMIT=500

Get a Gemini API key from Google AI Studio.

3. Run the development server

npm run dev

Open http://localhost:3000 in your browser.

Project Structure

app/
  page.tsx               # Main UI — editor, language/mode picker
  layout.tsx
  api/analyze/route.ts   # POST /api/analyze — validation, LLM call, response
components/
  Header.tsx
  OutputPanel.tsx        # Renders summary, issues, complexity, refactored code
lib/
  schema.ts              # Zod schemas for request and LLM response
  validation.ts          # Request validation and 500-line limit check
  rateLimit.ts           # In-memory per-IP rate limiter
  llm.ts                 # Gemini API integration
types/
  analysis.ts            # Shared TypeScript types

API

POST /api/analyze

Request body:

{
  "language": "javascript",
  "mode": "strict",
  "code": "// your code here"
}

Field	Type	Allowed values
language	string	javascript typescript python java cpp
mode	string	strict optimize refactor
code	string	Non-empty, max 500 lines

Success response 200:

{
  "success": true,
  "data": {
    "summary": "...",
    "issues": [
      {
        "type": "security",
        "severity": "high",
        "line": 12,
        "description": "...",
        "fix": "..."
      }
    ],
    "complexity": { "time": "O(n)", "space": "O(1)" },
    "refactoredCode": null
  }
}

Error response:

{
  "success": false,
  "error": "..."
}

Condition	Status
Invalid language, mode, or empty code	400
Code exceeds 500 lines	400
Rate limit exceeded	429
LLM or schema failure	500

Scripts

npm run dev      # Start development server
npm run build    # Production build
npm run start    # Start production server
npm run lint     # Run ESLint

License

MIT