Dirac Delta Labs · 2026-04-28 · major
Dirac — Open-Source Coding Agent Tops Terminal-Bench-2 on Gemini 3 Flash Preview
A Cline fork hits #1 on Terminal-Bench-2 with 65.2% running on Gemini 3 Flash Preview, edging out closed-source Junie CLI (64.3%) and the official Google harness baseline (47.8%). Apache-2.0, 937 stars in days.
A solo-built Cline fork takes #1 on Terminal-Bench-2 with a Flash-tier model — the harness, not the model, was the bottleneck.
Key specs
| License | Apache-2.0 |
|---|---|
| GitHub stars | 937 |
| Terminal bench 2 score | 65.2% |
| Junie cli score | 64.3% |
| Google official baseline | 47.8% |
| Show hn points | 367 |
What is it?
Dirac is an open-source CLI and VS Code coding agent forked from Cline by Dirac Delta Labs. The author submitted a Show HN on April 28 reporting Dirac scored 65.2% on the public Terminal-Bench-2 leaderboard using Gemini 3 Flash Preview, putting it ahead of closed-source Junie CLI (64.3%) and well ahead of Google's own harness baseline (47.8%) on the same model.
How does it work?
Three key tricks stack: hash-anchored edits identify code regions by content hash so the model never re-reads unchanged context; AST-native patching emits syntactically valid edits the agent doesn't have to retry; multi-file batching collapses several reads or edits into a single tool round-trip. Native tool calling only — no MCP. Custom skills load via an agents.md format.
Why does it matter?
It is a clean experimental data point that the agent harness — not the underlying model — is gating Terminal-Bench scores: a Flash-tier model in a tight harness beat agents running on much more expensive backends. Useful both as a low-cost day-to-day coder and as a reference design for harness builders.
Who is it for?
developers who want a low-cost CLI coding agent and harness authors looking for ideas worth copying.
Try it
npm install -g dirac-cli