A practical onboarding path for an existing serverless system

Onboarding to an AWS system is difficult when the architecture lives only in the memories of the people who built it. A resource inventory helps, but it does not explain ownership, critical paths, or the operational choices behind the resources.

Give the system a narrative

Start with one customer outcome and trace its API, events, workflows, data stores, and external dependencies. Pair that map with the decisions that matter: where retry is owned, which queues can be replayed, what roles are read-only, and where an operator looks first during an incident.

Then assign a safe first task: improve a runbook, validate an alarm, trace a non-critical event, or update a resource map. The task should create confidence without granting broad production authority.

Good onboarding turns an unfamiliar account into a system someone can explain and safely improve.