Rails at Scale company blog

How Ruby executes JIT code

by Stan Lo railsatscale.com published 2025-09-085 min read

Where does JIT-compiled code live? How does Ruby switch between bytecode and native execution? Why does TracePoint slow everything down? This post answers the JIT questions most Ruby developers have but rarely see explained.

Points

141

HN comments

29

Submissions

1

Cited by

0 commenters

Software EngineeringSystems & Performance2025

Related posts from the same era

Ghostty is leaving GitHub

Mitchell Hashimoto20263,521 points1,051 commentscited by 3 details

Astra can read and write weights to improve Qwen

RRikiya Takehi20262,956 points898 comments details

Git commands I run before reading any code

Principal Software Engineer & Codebase Rescue20262,338 points509 comments details

Reverse engineering Ticketmaster's rotating barcodes

conduition20242,305 points714 comments details

Uv is the best thing to happen to the Python ecosystem in a decade

Dr. Emily L. Hunt20252,214 points1,324 comments details

Anthropic acquires Bun

Bun Blog20252,192 points1,072 commentscited by 7 details