TLDR Dev · MISCELLANEOUS

I PUT A FULL JVM INSIDE A BROWSER TAB. IT "WORKS". TECHNICALLY. EVENTUALLY

bmarti44.substack.com9 min read

Summary from the TLDR Dev newsletter

JavaBox is a project that runs a full OpenJDK Java Virtual Machine entirely within a web browser tab, without requiring any server-side processing. This system involves a 227MB WebAssembly blob that emulates a Linux environment via QEMU, which then hosts OpenJDK, with a custom "CompileServer" daemon improving compile times. While technically functional, the system is slow, taking approximately 55 seconds to display "Hello World" from page load.