fast-dev-compaction
Codex port of fast-jev-compaction that re-injects Jev-selected verbatim history after compaction; the author advises against using it.
Overview
This repository (published as fast-jev-compaction for Codex) wraps Codex session compaction with Jev decisions. Before Codex compacts, every tool call and result is scored in fast requests; after compaction, the verbatim history Jev kept is re-injected as context. User and assistant text stays verbatim and in order. It is both an npm library and a Codex plugin using lifecycle hooks, porting tamaratran's original Claude Code adapter.
The README opens with a clear warning: the author does not recommend using it and calls it an experimental proof of concept. It cites a critique by Theo (t3.gg) arguing that pruning tool calls on a probability threshold misunderstands compaction: it discards reasoning traces frontier models do not expose, ignores that models are trained on their own compaction flows, and makes history edits trigger expensive cache rewrites. It is best read as a write-up of an idea.
What the decision model decides
| Type | Question | Answers |
|---|---|---|
| Yes / no | Is this tool call or result still needed?(inferred) | yes · no |
How it works
- Before compaction, score each tool call and result with Jev
- Let Codex compact natively
- Re-inject the Jev-kept verbatim history as context
Strengths
- Illustrates a verbatim-preservation approach
- Usable as an npm library
Caveats
- Author explicitly does not recommend using it
- Critiqued for breaking caches and ignoring hidden reasoning
- Proof of concept
Getting started
Not recommended for real work; see the README for installing the Codex plugin if experimenting.At a glance
- Type
- Plugin
- Status
- prototype
- Language
- TypeScript
- Runtime
- Codex plugin + npm library
- Has code
- yes
- License
- MIT
Use cases and integrations
How curated lists describe it
Context management: Codex port of the Jev-guided compaction idea, restoring context verbatim around a session compaction rather than summarizing it.
yibie/awesome-jevCodex plugin for context compaction, using Jev within session lifecycle hooks to preserve essential history while pruning noise.
logicrw/awesome-jev-projectsCodex port that restores Jev-selected verbatim history around native session compaction.
cobanov/awesome-jevCodex plugin: verbatim Jev-guided context restoration around session compaction. Port of tamaratran/fast-jev-compaction to Codex lifecycle hooks.
hellogumbo/awesome-jev
Frequently asked questions
Should I use it?
The author says no; it is an experimental proof of concept.
What is the critique?
Pruning by probability discards hidden reasoning, conflicts with trained compaction flows and breaks caching.
What is it ported from?
tamaratran/fast-jev-compaction for Claude Code.
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