Hydrating Files

Use crab hydrate when your working tree has Crab pointer files and you need the real content on disk.

crab hydrate --all
crab hydrate 'models/**'
crab hydrate --manifest .crab/manifests/ci.txt

Hydration reads each pointer, resolves its chunk metadata, downloads missing chunks from object storage or the local cache, writes the reconstructed file atomically, and verifies the result by hash.

Choose What to Hydrate

Use selective hydration in large repositories. CI jobs should normally hydrate only fixtures, models, or datasets needed by that job.

Typical Flows

# After clone
crab clone crab://team-bucket/ml-repo
cd ml-repo
crab hydrate 'models/**'

# After pulling changes
crab pull --remote origin

# Before switching context
crab dehydrate --all
git checkout experiment/new-architecture
crab hydrate 'models/**' 'data/eval/**'

Troubleshooting

• Already hydrated files are skipped.
• Failed files remain as pointers, so rerunning the same command is safe.
• Missing chunks usually mean the producing machine did not complete crab push or the remote store was modified outside Crab.
• For local recovery from a copy of the original file, use crab hydrate --recover-from <path>.

Verify materialized content

Check the selected path instead of assuming a zero exit status hydrated every file in a broad pattern:

crab status
crab why models/v2.bin
test -s models/v2.bin

crab status gives the repository summary, while crab why explains the tracking rule and current representation for one path. The final shell check only proves that the file is nonempty; Crab's hydration path separately checks the reconstructed content hash before replacing the pointer atomically.

Hydration changes the working-tree representation but not the committed Git blob. A normal Git diff may therefore notice that full content differs from the pointer stored in the index. Use Crab state commands to distinguish expected materialization from an edited file before resetting anything.

For full pattern precedence, manifest format, output modes, and options, see the crab hydrate reference.