Content guard

This is a public repository about a private activity. The guard keeps course material, the names of institutions, platforms and people, captured lectures, credentials and personal data out of it.

Layers

Layer	When	What
.gitignore	Always	Capture output, decks, recordings, .env, eval results, private session cases
pre-commit hook	git commit	Scans staged files
commit-msg hook	git commit	Scans the message
pre-push hook	Any push	Scans every commit the remote lacks (message, author, paths, files) and the whole tree
tools/publish.sh	The only supported push	Same checks, then pushes; a plain git push to origin fails because its push URL is disabled
CI	After a push or on a pull request	Scans the tree and the pushed commits again

Turn it on once per clone: tools/setup_hooks.sh.

What it looks for

1. Blocked terms. Stored only as SHA-256 hashes in tools/guard/blocked_terms.sha256, so the repository never spells out what it must not contain. Text is lower-cased and split into words; every run of one to six words is hashed and compared. Words of five letters or more are also found when glued inside a longer word. Ordinary words that contain a blocked one go in allow_tokens.txt.
2. Your plaintext list, .guard/terms.local.txt, if present. It is ignored by git.
3. Forbidden paths and types: lecture output, notes, feedback, decks, documents, recordings, databases, .env, images outside the docs site.
4. Secrets: private keys, common token formats, credential assignments.
5. Personal data: absolute home-directory paths, e-mail addresses other than no-reply and example addresses.
6. Files over 1 MB.

Adding a term

echo "some name" >> .guard/terms.local.txt
tools/guard/make_hashes.py .guard/terms.local.txt
git add tools/guard/blocked_terms.sha256 && git commit -m "guard: add a blocked term"

When it stops you

It prints the file, the line and the text it found in your file. Replace the name with a generic one ("the institute", "the course portal", learn.example.edu), or move the file to an ignored folder, and commit again. If the hit is an ordinary word, add that word to allow_tokens.txt and say why in the commit message.

Limits

• It prevents accidents, not intent. Hooks can be skipped with --no-verify and a push URL can be typed by hand. CI detects that afterwards, but a public push cannot be recalled: anything pushed should be treated as published.
• Hashes are not secrecy. Anyone can test a guess against the list. It keeps names out of the text and out of search; it does not hide them from someone who already suspects them.
• It cannot recognise paraphrase. A lecture's ideas restated in your own words pass. Judgement is still yours.
• It is not legal advice. It implements a cautious policy: name nothing, quote nothing.