What you are learning
Keyvaultline is choosing the right credential type and keeping secrets out of git. The teaching focus is Credentials (API keys, OAuth clients, service accounts, secrets hygiene).
Work in order. Early parts set vocabulary and environment; later parts assume the earlier checkpoints.
How to use these lessons
Read the goal, open the matching GitHub folder, complete the lab or exercises, then return for the explanation. If a command fails, check you are in the numbered folder first.
Parts in order
Each chapter below is one checkpoint in this track.