# facebook/prepack

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14,118 stars · 412 forks · JavaScript · NOASSERTION · archived

## Links

- GitHub: https://github.com/facebook/prepack
- Homepage: http://prepack.io
- awesome-repositories: https://awesome-repositories.com/repository/facebook-prepack.md

## Description

Prepack is a build-time transformation tool and static analysis engine designed to optimize JavaScript source code. By executing code during the build process, it evaluates program logic and state to precompute results, effectively simplifying complex operations before the application is deployed.

The tool functions as a bundle optimizer that integrates into existing development pipelines to refine application logic. It employs abstract interpretation and symbolic execution to track program behavior across various paths, allowing it to perform constant folding, eliminate unreachable code, and simplify subexpressions. By capturing the final heap state and serializing it into optimized source code, the tool reduces the complexity of the resulting bundle.

These capabilities support broader performance engineering goals by minimizing resource consumption and improving execution efficiency in target environments. The project provides a command-line interface for automation and is intended for use within standard module bundling workflows.

## Tags

### Programming Languages & Runtimes

- [JavaScript Optimizers and Minifiers](https://awesome-repositories.com/f/programming-languages-runtimes/javascript-optimizers-and-minifiers.md) — Reduces the size and complexity of JavaScript files during the build process to improve performance.
- [Abstract Interpretation Frameworks](https://awesome-repositories.com/f/programming-languages-runtimes/abstract-interpretation-frameworks.md) — Employs abstract interpretation to evaluate program logic and state during the build process.
- [Optimized Serialization Engines](https://awesome-repositories.com/f/programming-languages-runtimes/ahead-of-time-compilation/serialization-code-generators/optimized-serialization-engines.md) — Generates a new program by transforming the computed heap into efficient code through constant folding and subexpression elimination. ([source](https://github.com/facebook/prepack/wiki/Suggested-reading))
- [Constant Folding](https://awesome-repositories.com/f/programming-languages-runtimes/constant-folding.md) — Performs constant folding to replace complex expressions with pre-calculated results at build time.
- [Build-Time Interpreters](https://awesome-repositories.com/f/programming-languages-runtimes/javascript-engines/embedded-javascript-interpreters/build-time-interpreters.md) — Executes source code during the build process to determine the final state and effects of the program. ([source](https://github.com/facebook/prepack/wiki/Suggested-reading))
- [Symbolic Execution Engines](https://awesome-repositories.com/f/programming-languages-runtimes/runtime-execution-environments/runtime-environments/runtimes/graph-symbolic-execution-engines/symbolic-execution-engines.md) — Tracks operations on abstract values to evaluate code behavior across all possible environment interactions. ([source](https://github.com/facebook/prepack/wiki/Suggested-reading))
- [Build-Time Transformation Tools](https://awesome-repositories.com/f/programming-languages-runtimes/source-code-compilers/build-time-transformation-tools.md) — Integrates with module bundlers to perform constant folding and subexpression elimination.

### Development Tools & Productivity

- [JavaScript Execution Optimizers](https://awesome-repositories.com/f/development-tools-productivity/performance-optimization-tools/javascript-execution-optimizers.md) — Simplifies complex code logic during the build process to ensure faster execution in target environments. ([source](https://github.com/facebook/prepack#readme))

### Software Engineering & Architecture

- [Control-Flow Graph Generation](https://awesome-repositories.com/f/software-engineering-architecture/control-flow-logic-models/control-flow-graph-generation.md) — Generates control flow graphs to identify and eliminate unreachable code paths.
- [JavaScript Optimization](https://awesome-repositories.com/f/software-engineering-architecture/performance-reliability/performance-optimization/application-performance-tuning/javascript-optimization.md) — Refines application logic through constant folding and loop unrolling to minimize resource consumption.
- [Static Analysis Engines](https://awesome-repositories.com/f/software-engineering-architecture/static-analysis-engines.md) — Evaluates execution paths and abstract values to simplify complex logic before code deployment.

### System Administration & Monitoring

- [Heap State Serializers](https://awesome-repositories.com/f/system-administration-monitoring/heap-memory-monitoring/heap-snapshot-capturers/heap-state-serializers.md) — Captures the final heap state and serializes it into optimized source code for the target environment.

### Testing & Quality Assurance

- [Static Code Analysis](https://awesome-repositories.com/f/testing-quality-assurance/static-code-analysis.md) — Evaluates JavaScript execution paths at build time to simplify logic before deployment.

### Part of an Awesome List

- [Build Tools](https://awesome-repositories.com/f/awesome-lists/devtools/build-tools.md) — Tool for optimizing JavaScript code via pre-execution.