https://github.com/restsend/pipa
A fast, minimal ES2023 JavaScript runtime built in Rust.
https://github.com/restsend/pipa
javascript rust-library script-engine
Last synced: 10 days ago
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A fast, minimal ES2023 JavaScript runtime built in Rust.
- Host: GitHub
- URL: https://github.com/restsend/pipa
- Owner: restsend
- Created: 2026-05-20T06:20:50.000Z (24 days ago)
- Default Branch: main
- Last Pushed: 2026-05-20T07:01:04.000Z (24 days ago)
- Last Synced: 2026-05-20T09:57:46.381Z (24 days ago)
- Topics: javascript, rust-library, script-engine
- Language: Rust
- Homepage:
- Size: 403 KB
- Stars: 4
- Watchers: 0
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
Awesome Lists containing this project
README
# pipa (枇杷) - A fast, minimal ES2023 JavaScript runtime built in Rust.
## Features
- **ES2023 compliant** — implements the ECMAScript 2023 specification
- **Async/await built-in** — first-class async/await support without transpilation
- **Bytecode support** — compile JavaScript to `.jsc` bytecode files for fast loading and execution, with configurable optimization levels (`-O0` through `-O3`)
- **Fast** — outperforms QuickJS in benchmarks
- **Small** — ~5.2 MB binary (with `repl` feature)
- **Zero-dependency** built-in implementations for:
- Regex/JSON/Base64/BigInt
- Unicode
- `fetch` (HTTP client), `rusttls` required
- WebSocket
- Server-Sent Events (SSE)
No external C libraries or system dependencies for the above — everything is implemented from scratch in Rust.
## Benchmarks (2026-05-31)
V8 benchmark suite comparison (higher is better):
| Benchmark | qjs | node | boa | pipa | vs qjs |
|------------------------|-------|--------|-------|-------|--------|
| Richards | 980 | 46846 | 133 | 895 | -8.7% |
| DeltaBlue | 951 | 94979 | 140 | 923 | -2.9% |
| Crypto | 1059 | 60072 | 125 | 993 | -6.2% |
| RayTrace | 1462 | 79697 | 315 | 965 | -34.1% |
| EarleyBoyer | 2107 | 95129 | 281 | 1307 | -38.0% |
| RegExp | 330 | 12703 | 41.6 | 1016 | +207.9% |
| Splay | 2405 | 48609 | 536 | 2904 | +20.7% |
| NavierStokes | 1793 | 56392 | 288 | 1825 | +1.8% |
| **SCORE (total)** | **1201** | **53836** | **184** | **1240** | **+3.2%** |
Ranking: **#1 node** (53836) · **#2 pipa** (1240) · **#3 qjs** (1201) · **#4 boa** (184)
## test262 Compatibility (2026-05-31)
Tested against [tc39/test262](https://github.com/tc39/test262) (excluding `intl402`).
| Category | Tests | Pass Rate | Notes |
|----------|-------|-----------|-------|
| **Core Builtins** | | | |
| Math | 324 | **100%** (324/324) | |
| Boolean | 50 | **100%** (50/50) | |
| parseFloat | 96 | **100%** (96/96) | |
| parseInt | 104 | **100%** (104/104) | |
| Number | 339 | **100%** (339/339) | |
| Object.is | 21 | **100%** (21/21) | |
| Object.defineProperty | 1131 | **98.8%** (1118/1131) | |
| Object.create | 320 | **99.4%** (318/320) | |
| Object.getPrototypeOf | 39 | **100%** (39/39) | |
| Date | 594 | **93.6%** (556/594) | |
| global | 29 | **96.6%** (28/29) | |
| Infinity | 6 | **100%** (6/6) | |
| eval | 10 | **80.0%** (8/10) | |
| URI encode/decode | 118 | **77.9%** (92/118) | |
| Function | 507 | **85.2%** (432/507) | |
| **Other Builtins** | | | |
| Symbol | 98 | **73.5%** (72/98) | |
| JSON | 165 | **50.9%** (84/165) | |
| Error | 92 | **44.6%** (41/92) | |
| RegExp | 1878 | **42.3%** (794/1878) | |
| String | 301 | **17.0%** (51/301) | |
| Reflect | 153 | **20.9%** (32/153) | |
| Map | 203 | **21.2%** (43/203) | |
| Set | 382 | **18.3%** (70/382) | |
| BigInt | 77 | **23.4%** (18/77) | |
| Promise | 676 | **5.5%** (37/676) | Limited async support |
| Proxy | 311 | **0%** (0/311) | Not yet implemented |
## Usage
```bash
cargo install pipa-js
# Run a script
pipa script.js
# Run precompiled bytecode
pipa script.jsc
# Compile JavaScript to bytecode
pipa -compile input.js output.jsc
# Disassemble bytecode (debugging)
pipa -diss script.jsc
# Specify optimization level (default: -O2)
pipa -O3 script.js
# Start REPL (requires the repl feature)
pipa
```
## Embedding in Rust
Use pipa-js as a library to embed JavaScript in your Rust project:
```toml
[dependencies]
pipa-js = "0.1.2"
```
### Evaluate JavaScript
```rust
use pipa::{JSRuntime, eval};
let mut rt = JSRuntime::new();
let mut ctx = rt.new_context();
let val = eval(&mut ctx, "1 + 2").unwrap();
assert_eq!(val.get_int(), 3);
```
### Read strings & values from JavaScript
```rust
use pipa::{JSRuntime, eval};
let mut rt = JSRuntime::new();
let mut ctx = rt.new_context();
eval(&mut ctx, r#"
function greet(name) {
return "Hello, " + name + "!";
}
"#).unwrap();
let val = eval(&mut ctx, r#"greet("world")"#).unwrap();
assert!(val.is_string());
let s = ctx.get_atom_str(val.get_atom());
assert_eq!(s, "Hello, world!");
```
### Call custom Rust functions from JavaScript
```rust
use pipa::{JSRuntime, eval, JSValue};
fn js_print(ctx: &mut pipa::JSContext, args: &[JSValue]) -> JSValue {
for arg in args {
if arg.is_string() {
print!("{}", ctx.get_atom_str(arg.get_atom()));
} else if arg.is_int() {
print!("{}", arg.get_int());
}
}
println!();
JSValue::undefined()
}
let mut rt = JSRuntime::new();
let mut ctx = rt.new_context();
ctx.register_global_builtin("print", 1, js_print);
eval(&mut ctx, r#"print("hello from Rust!")"#).unwrap();
```
### Async/await with event loop
```rust
use pipa::{JSRuntime, eval, eval_async};
let mut rt = JSRuntime::new();
let mut ctx = rt.new_context();
eval_async(&mut ctx, r#"
var result = null;
(async () => {
result = await fetch("https://httpbin.org/json");
})();
"#).unwrap();
let val = eval(&mut ctx, "JSON.stringify(result)").unwrap();
println!("{}", ctx.get_atom_str(val.get_atom()));
```
> Requires the `fetch` feature (enabled by default). `eval_async` is `eval` + `run_event_loop` in one call.
### Bytecode compilation
```rust
use pipa::{JSRuntime, eval, compile_to_register_bytecode};
let mut rt = JSRuntime::new();
let mut ctx = rt.new_context();
// Compile JavaScript to register-based bytecode
let (code, constants) = compile_to_register_bytecode(
&mut ctx,
"function fib(n) { return n < 2 ? n : fib(n-1) + fib(n-2); } fib(20)",
).unwrap();
// code: Vec, constants: Vec
assert!(!code.is_empty());
```
## Build
```bash
# Default build (includes REPL, fetch, and process support)
cargo build --release
# Minimal build (no REPL, no fetch, no process)
cargo build --release --no-default-features
```
> If using pipa as a library dependency and you don't need REPL/fetch/process features, add it with `default-features = false`:
> ```toml
> [dependencies]
> pipa-js = { version = "0.1.1", default-features = false }
> ```
## License
MIT