COBOL Copilot

A free, open-source COBOL IDE and modernization toolkit. Analyze, edit, explain, translate, and test legacy COBOL codebases — powered by AI through the Quantum AI SDK.

Built with Rust + Tauri 2 + Svelte. Runs on macOS, Windows, Linux, iOS, and Android.

Features

IDE

• Code Editor with COBOL syntax highlighting, line numbers, and Cmd+S save
• Paragraph & full-file editing modes
• Split view for side-by-side COBOL and translated code
• Context menu with go-to-definition, find callers/callees, impact analysis

AI-Powered Analysis

• Instant Explanations — click any paragraph for plain-English business logic breakdown
• Impact Analysis — see what breaks when you change a field or paragraph
• Code Translation — generate equivalent Rust, Python, or Go code
• Test Generation — create test cases from business logic
• Interactive Chat — ask questions about your codebase
• Documentation Generation — auto-generate program docs

GitHub Integration

• Sign in with GitHub CLI — picks up gh auth credentials automatically
• Repos Dashboard — total repos, stars, languages, activity breakdown, size charts
• Remote Browser — navigate any GitHub repo's file tree, click COBOL files to load
• Search — find COBOL repositories across all of GitHub
• Clone & Load — one-click clone and project import

Git Operations

• Repository Status — branch, ahead/behind, staged/modified/untracked files
• Branch Management — switch branches, pull, fetch
• Commit Log — recent commit history with authors and timestamps
• Local File Browser — navigate cloned repos to find COBOL files

Project Management

• Batch Analysis — scan entire folders of COBOL programs
• Batch Translation — translate all programs to a target language
• Dossier Mode — generate comprehensive explanations for every paragraph
• Project Dashboard — file counts, complexity stats, risk distribution, LOC
• Knowledge Base — save and organize analysis reports
• Translation Rules Engine — learnable pattern library for COBOL-to-Rust mappings

Themes

11 built-in themes including 3 light modes:

Architecture

cobol-copilot/
├── src-tauri/                    # Rust backend (Tauri 2)
│   ├── src/
│   │   ├── parser/               # COBOL lexer, AST, symbol table
│   │   ├── analyzer/             # Dependency graphs, impact analysis
│   │   ├── llm/                  # AI providers (Quantum SDK + legacy)
│   │   ├── translator/           # COBOL → Rust/Python/Go code gen
│   │   ├── commands/             # Tauri IPC commands
│   │   │   ├── mod.rs            # Core commands + LlmBackend
│   │   │   ├── git_commands.rs   # Local git operations (qe-git)
│   │   │   ├── github_commands.rs # GitHub API integration
│   │   │   └── storage_commands.rs
│   │   ├── scanner/              # Batch COBOL scanning
│   │   ├── testing/              # Migration test harness
│   │   ├── storage/              # SQLite persistence
│   │   └── graph/                # SurrealDB knowledge base
│   └── Cargo.toml
└── ui/                           # Svelte + TailwindCSS frontend
    └── src/
        ├── lib/
        │   ├── components/       # 30+ Svelte components
        │   ├── stores.ts         # Reactive state + themes
        │   └── tauri.ts          # TypeScript IPC wrappers
        └── routes/

AI Providers

COBOL Copilot supports multiple AI backends through a unified LlmBackend:

Quantum AI (Recommended)

Single API key for all models — Claude, Gemini, Grok, DeepSeek:

Settings → INIT_LLM → Quantum AI → Enter API key

Get a key at quantumencoding.ai/developers

Direct Providers (Legacy)

Requires the summon_ai binary and per-provider environment variables:

Building

Prerequisites

• Rust 1.75+
• Node.js 18+
• npm or pnpm

Development

cd ui && npm install
cd ../src-tauri && cargo tauri dev

Production Build

cd src-tauri && cargo tauri build

GitHub Integration Setup

COBOL Copilot uses the GitHub CLI for authentication — no OAuth flow needed:

brew install gh
gh auth login

Once authenticated, the GIT tab shows your repos dashboard, search, and remote file browser.

Supported COBOL Features

• Fixed-format (columns 1-6 sequence, 7 indicator, 8-72 code)
• IDENTIFICATION, ENVIRONMENT, DATA, PROCEDURE divisions
• WORKING-STORAGE, LINKAGE, FILE, LOCAL-STORAGE sections
• PIC clauses with automatic type inference
• PERFORM, CALL, COPY, GO TO statements
• EXEC SQL / END-EXEC blocks (DB2)
• EXEC CICS / END-EXEC blocks (transaction processing)
• 88-level condition names
• REDEFINES, OCCURS, DEPENDING ON clauses
• Ambiguity detection for unclear control flow

Tech Stack

License

MIT