What you can now build, and what the exam checks

Course 1 was building safely. Course 2 was rebuilding. Course 3 was testing. This one was composing — and composition is where most personal projects quietly fail.

The part that was never about dashboards

You can say where state lives. Panel-local, shared, persisted — and you know that shared state hidden inside a component is the bug that costs a weekend. That question applies to every application with more than one screen.

You can migrate persistence without losing data. Read-with-fallback, upload-once-then-flag, remove-fallback. Three revertible steps rather than one hopeful commit, and a version column because two tabs will both write.

You can design a contract before an implementation. Data in, config in validated, communication out, no sibling imports. Handing an assistant a contract instead of a feature request is the single biggest quality difference in this course.

You can price a feature before building it. The union of what your panels need, times the published cost, times how often. That is why you can say your alert loop needs 936 calls a day without deploying anything.

What is still missing

Your cockpit runs on your machine, for you. It has no CI beyond the key scan, no documentation anyone else could follow, no dependency audit, no error reporting, and nothing that keeps it alive when you stop paying attention to it.

That is course 5, and its wall is the one the whole track has been building toward: continuity. A tool that is shipped is a tool that has to keep working.

What the exam asks

Ten questions, seventy percent to pass, twenty-four hour cooldown, drawn from a pool so a retake is a different paper. Every fixture is fixed. Expect:

• Price a refresh. A panel list and the measured cost table; you give calls per refresh and per day.
• Place the state. A piece of state, and you say panel-local, shared or persisted, and why.
• Find the loop. A cross-panel selection wiring that feeds back on itself; you name the missing guard.
• Order the migration. The three persistence steps, out of order; you fix them and say what breaks otherwise.
• Read the timestamps. A multi-symbol response with differing times; you say what the header should show.
• Pick the error. A status code and what the panel should say — 402, 429 and 404 are different situations.

Before you sit it

Open your cockpit and force all five panel states by hand, then read your REVIEW.md against the running product. If the review passes but the product feels wrong to use, trust the feeling and find out why — a checklist that agrees with a bad experience is an incomplete checklist, and improving it is the actual skill.

Try it now

Write the one-paragraph description of your cockpit you would give someone else: what it is for, what it shows, what it cannot do. If that paragraph is hard to write, the cockpit is doing too many things — and course 5 opens by asking you to write it properly.