Building the Bun JavaScript Runtime from Source: A Bootstrapping Journey
By
zerf
4mo ago· 9 min readen
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Summary
The article details the author's technical journey of building the Bun JavaScript runtime from source without using its pre-built binaries, a process known as bootstrapping. The author faced challenges when trying to install OpenCode for LLM-assisted coding, which required Bun, but found that neither OpenCode nor Bun were available in their Linux distribution's package repositories. The article chronicles the step-by-step process of compiling Bun from source, including dealing with dependencies, build system issues, and the technical complexities involved in creating a self-contained build of the JavaScript runtime toolkit.
Key quotes
· 5 pulledThis article describes my journey running the build system for the Bun JavaScript toolkit without relying on any of its usual binary dependencies—namely itself.
It all started when I wanted to try OpenCode for LLM-assisted coding. I found that it wasn't easy to install—my distro packaged neither OpenCode itself, nor Bun, the JavaScript runtime used by OpenCode.
The aur didn't come to the rescue either as the latest revision of the Bun package failed to build.
Note: Bun was packaged for Arch Linux on 2025-12-30 🎉! However Debian, Fedora, and Ubuntu still do not package it.
I also uncovered an unf
My journey building the Bun JavaScript runtime from source.
