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Bare Runtime Reference
Reference for the Holepunch Bare runtime — the JavaScript runtime used by SPLectrum for prototyping and targeted for production deployment.
What Bare Is
Bare is a small, modular JavaScript runtime for desktop and mobile. Like Node.js, it provides an asynchronous, event-driven architecture built on libuv. Unlike Node.js, it ships with no standard library — everything is a userland module installed via npm. This makes it minimal by design: what you compose in is what exists.
This aligns directly with the architecture of absence: capabilities are present because they were composed in, not because they came bundled.
Source: https://github.com/holepunchto/bare
Installation
npm i -g bare
Prebuilt binaries included for Tier 1 platforms.
Architecture
Bare is built on two dependencies:
- libjs — low-level V8 bindings (https://github.com/holepunchto/libjs)
- libuv — asynchronous I/O event loop (https://github.com/libuv/libuv)
The runtime itself provides only three things:
- A module system (CJS and ESM with bidirectional interop)
- A native addon system (static and dynamic)
- Lightweight threads with synchronous joins
Everything else — filesystem, networking, crypto, streams — is a separately installed npm module.
Key Differences from Node.js
| Aspect | Node.js | Bare |
|---|---|---|
| Standard library | Built-in | None. All userland. |
process global |
Always available | Not present. Require explicitly. |
Buffer global |
Always available | Not present. Require explicitly. |
| Module system | CJS or ESM (one-way) | CJS and ESM (bidirectional) |
| Mobile support | Not a goal | Core goal. Android/iOS Tier 1. |
| Embedding | Difficult | Core goal. Clean C API. |
| Streams | Node.js streams | streamx-based |
CLI
bare [flags] [filename] [...args]
| Flag | Description |
|---|---|
--version, -v |
Print version |
--eval, -e <script> |
Evaluate inline |
--print, -p <script> |
Eval and print |
--inspect |
V8 inspector |
--expose-gc |
GC APIs |
No script — starts REPL.
Reference Pages
- Dual-Runtime Code — writing code that runs on both Bare and Node.js
- Global API — the Bare global namespace
- Module Catalog — all modules with sources and version numbers
- Module System — resolution, conditions, protocols
- Platforms — supported platforms
- Sources — all documentation links
Module npm versions verified April 2026.