checkpoint.ts

Stop rerunning 10 functions to debug the 11th.

Interactive checkpoint system for TypeScript/JavaScript development. Inspect state, skip functions, inject values, profile execution.

Like Minecraft parkour map checkpoints, but for your code

Written in Rust 🦀 | Works with Bun, Node, Deno

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Quick Start

# Install
cargo install checkpoint-ts

# Run with checkpoints
checkpoint myfile.ts

# Use specific runtime
checkpoint myfile.ts --interpreter bun # deno, node

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How it works

Checkpoint transforms your code by injecting instrumentation points at function calls and variable assignments. When execution hits a checkpoint, it pauses and opens an interactive TUI where you can:

• Inspect current variable states
• Edit variable values on the fly
• Skip function execution and inject cached results
• Continue execution with modified state
• Profile execution time for each function

The system uses AST analysis to identify checkpoint opportunities and maintains a serializable execution context throughout your program's runtime.

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Features

Interactive Debugging Pause execution at any function call and inspect the complete variable state without restarting your program.

Function Skipping Skip expensive function calls during debugging and use cached or manually injected return values.

State Manipulation Edit variables in real-time through the TUI and continue execution with your modifications.

Execution Profiling Measure and track execution time for each function call with millisecond precision.

Runtime Agnostic Works seamlessly with Bun, Node.js, and Deno through adaptive runtime detection.

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Installation

From Cargo

cargo install checkpoint-ts

From Source

git clone https://github.com/ErenayDev/checkpoint-ts
cd checkpoint.ts
cargo build --release

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Usage

Basic Usage

checkpoint script.ts

Runtime Selection

checkpoint script.ts --interpreter bun
checkpoint script.ts --interpreter node
checkpoint script.ts --interpreter deno

Pre-instrumented Files

checkpoint --instrumented script.instrumented.ts

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TUI Interface

The terminal interface provides three main views:

Checkpoint Navigator Shows current execution position, available checkpoints, and execution timeline.

State Editor Interactive table for viewing and editing variable values at the current checkpoint.

Execution Visualizer Performance metrics and execution flow visualization with timing information.

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Supported Features

• Function-level checkpoints
• Variable state inspection and editing
• Execution timing and profiling
• Cached result injection
• TypeScript and JavaScript support
• ES modules and CommonJS compatibility
• Async/await support (experimental)

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Limitations

• Circular references in objects are not fully supported
• Some complex TypeScript syntax may not be instrumented correctly
• Async operations have limited checkpoint support
• Maximum object depth for serialization is 10 levels

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Contributing

We welcome contributions! Please see our Contributing Guide for details.

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License

Copyright (c) ErenayDev [email protected]

This project is licensed under the MIT license (LICENSE or http://opensource.org/licenses/MIT)

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Sponsors

Special thanks to our sponsors who make this project possible:

#1 Sponsors

• Become a sponsor

#2 Sponsors

• Become a sponsor

#3 Sponsors

• Become a sponsor

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Acknowledgments

Built with:

• SWC for TypeScript/JavaScript parsing
• Ratatui for terminal user interface
• Tokio for async runtime support