gfix

A Git helper for adding staged changes to an older commit, rather than only the latest one. Git is a version-control system that records changes to code over time.

In plain words
What is it for?
Use it when a fix belongs inside a previous commit, passing that commit's ID and optionally a replacement commit message.
Why use it?
It avoids manually performing the multi-step history editing needed to amend an earlier commit and includes handling for local unstaged changes and conflicts.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/ryanb/dotfiles/gfix
Any agent
npx skills add ryanb/dotfiles --skill gfix
Clone the repo
git clone --depth 1 https://github.com/ryanb/dotfiles

Made for: Claude Code, Codex.

Per session 14 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 876 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00014 $0.00876
Opus 5 $0.00007 $0.00438
Sonnet 5 $0.00003 $0.00175
Haiku 4.5 $0.00001 $0.00088

Measured yesterday against content hash 95a39da449ef, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

gfix scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

claude/skills/gfix/SKILL.md · 62 lines

How it starts

The opening of the file, as written. The whole thing — 62 lines — stays where its author put it; the contents beside it link to each section on GitHub.

gfix — Amend a Past Commit

Use the gfix shell command to fold staged changes into a commit that is not the most recent. This is the preferred way to amend historical commits in this repo.

MUST use gfix. When this skill is loaded, every modification to a past commit goes through the gfix command. Do not reach for git rebase -i, hand-crafted fixup!/amend! commits, or GIT_SEQUENCE_EDITOR=true git rebase --autosquash directly — gfix already does all of this, with stash/restore guarantees and conflict handling.

How gfix works

Source: ~/code/dotfiles/plugins/git.zsh (the gfix function)

gfix [-m <message>] <commit-sha> does the following:

  1. Guards against running during an in-progress git operation (rebase, merge, cherry-pick, etc.)
  2. Stashes any unstaged changes (preserving the index)
  3. Creates a fixup commit from whatever is currently staged:
    • With no -m: git commit --fixup <commit-sha> (content-only fixup)
    • With -m <message>: creates a manual amend! commit with subject amend! <original-subject> and body <message>, which autosquash then folds into the target (replacing its message, and including any staged changes; --allow-empty is used if nothing is staged)
  4. Runs GIT_SEQUENCE_EDITOR=true git rebase -i --autosquash <commit-sha>^ to automatically squash the fixup into the target commit
  5. Restores any stashed unstaged changes

When to use gfix

Use gfix when you need to amend a commit that is not the HEAD commit. For example:

  • A review comment asks for a change to code introduced 3 commits ago
  • You notice a typo or bug in an earlier commit while working on something else
  • You want to keep a clean, logical commit history where each commit is self-contained

If you only need to amend the most recent commit, use git commit --amend instead.

Steps

  1. Determine the safe range — The target commit must be within the current branch's own commits, not on or before the base branch. Find the base branch via the tracked parent in git config branch.$(git branch --show-current).parent, falling back to bin/base-branch if that script exists. As a last resort, ask the user.

Read the full file on GitHub · 62 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 62 lines · 14 tokens per session scan A 95a39da449ef

Subscribe to this mod's changes

gfix is a skill published in the GitHub repository ryanb/dotfiles (2,399 stars, last pushed 12d ago), licensed MIT. It adds 14 tokens to every session and 876 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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