A .gitignore that is only yours

Every shared repository eventually collects files that are yours alone. A scratch script, a notes.md, a dump of production data you are debugging against, the config for an editor nobody else on the team uses.

They do not belong in the project’s .gitignore, because they are not the project’s business. But they do need ignoring, because git status full of noise is git status nobody reads.

Git has two answers. The first is simpler than most people realise, and the second has a sharp edge.

The simple one: .git/info/exclude

This file already exists in every repository you have ever cloned, and it does exactly this job. Same syntax as .gitignore, never committed, applies only to your copy.

echo "notes.md" >> .git/info/exclude
echo "scratch/" >> .git/info/exclude

That is the whole feature. No configuration, nothing to set up, nothing that can conflict with anything else.

Its one real drawback is that it is buried inside .git/, which makes it easy to forget and awkward to edit — and if you ever delete and re-clone the repository, it goes with it.

The other one: a file in the working tree

If you would rather have the list somewhere you can see it, you can keep it as a normal file and point Git at it.

Create it:

touch .local.gitignore

Stop Git from offering to commit it, using the mechanism above:

echo ".local.gitignore" >> .git/info/exclude

Tell Git to read it:

git config --local core.excludesfile .local.gitignore

Now it behaves like a .gitignore that nobody else has:

echo "my-secret-file.txt" >> .local.gitignore
echo "debug_logs/" >> .local.gitignore

The sharp edge

core.excludesFile is a single value, not a list. Setting it locally does not add your file to the ones Git already consults — it replaces whatever was there, which for most people is the global ignore file in ~/.gitignore_global.

Here is that happening, in a fresh repository:

$ git config --local core.excludesfile ~/.gitignore_global
$ git status --short
?? local-secret.txt          # .DS_Store etc. correctly ignored
 
$ git config --local core.excludesfile .local.gitignore
$ git status --short
?? global-ignored.txt        # ← back, and it will not come out again
?? .local.gitignore

Everything your global file was quietly handling — .DS_Store, *.swp, .idea/, whatever you accumulated over the years — stops being ignored in this repository. Nothing warns you. You just start seeing noise you have not seen in so long that you may not connect it to a setting you changed last week.

That caveat is why I use .git/info/exclude and not this. The convenience of having the file in the working tree is real, and it is not worth switching off a safety net you set up years ago and have not thought about since.

Before you undo a commit

One more, which applies to both approaches.

Ignored files are untracked files. Git is not storing them anywhere, so anything that rewinds your working tree — git reset --hard, git checkout of another branch over them, git clean most of all — treats them as expendable, because as far as Git is concerned they never existed.

# Will delete every ignored file, including the ones you meant to keep.
git clean -fdx

If you are about to rewind history and there is anything in those directories you care about, copy it out first. There is no reflog for a file that was never committed.