Retry & Offline Fallbacks
Recover gracefully from transient failures.
Retry & Offline Fallbacks is a free Kotlin Multiplatform Academy lesson on CoddyKit — lesson 4 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the Kotlin Multiplatform Academy learning path, one of 4 lessons in the course, and your progress syncs across the web and the CoddyKit app.
Some Failures Are Temporary
A timeout often clears on a second try. Treat transient errors as worth retrying, not as a final dead end for the user.
Retry the Right Errors
Only retry transient kinds like network timeouts. A parsing error will fail again every time, so retrying it just wastes effort.
A Simple Retry Loop
Wrap the call in a small loop that tries a few times. If it finally succeeds, return Success; otherwise fall through to Failure.
repeat(3) {
val r = fetch()
if (r is Success) return r
}Back Off Between Tries
Hammering instantly rarely helps. Add a growing delay between attempts so a struggling server gets room to recover.
delay(attempt * 500L)Cap Your Attempts
Never loop forever. A hard max of two or three tries keeps the user from waiting endlessly on a truly down service.
Reach for the Cache
When retries are exhausted, look in local storage. Showing slightly old data beats showing an empty, broken screen.
Serve Stale, Then Refresh
A friendly pattern is stale-while-revalidate: display cached data instantly, then quietly fetch fresh data in the background.
Tell the User It Is Offline
When you fall back to cache, set an offline flag in your state so the UI can show a subtle banner about stale content.
Coroutines Make It Clean
Because this runs in a suspend function, delays and retries read like simple sequential code, with no callbacks or threads to manage.
suspend fun loadWithRetry(): Result<User>Keep It Cancellable
Respect cancellation: if the screen closes mid-retry, structured concurrency stops the loop so you never leak background work.
One Resilient Entry Point
Callers just invoke loadWithRetry and get the best outcome: fresh data, cached data, or a clear Failure, all decided in shared code.
Quick Check
Think about which failures deserve another attempt.
Recap
You retried transient errors with backoff, capped attempts, fell back to cached data with an offline flag, and kept it cancellable in shared code. 🔄
Frequently asked questions
Is the “Retry & Offline Fallbacks” lesson free?
Yes — the full text of “Retry & Offline Fallbacks” is free to read here on the web, and the Kotlin Multiplatform Academy course includes 4 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the Kotlin Multiplatform Academy course, upgrade to CoddyKit PRO.
What will I learn in “Retry & Offline Fallbacks”?
Recover gracefully from transient failures. You practise Kotlin Multiplatform Academy with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.
Do I need any experience to start Kotlin Multiplatform Academy?
No prior experience is required. Kotlin Multiplatform Academy on CoddyKit is structured for beginners through advanced learners; this is — lesson 4 of 4, so you can start here or from the beginning and move at your own pace.
How long does the “Retry & Offline Fallbacks” lesson take?
Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.
Can I write and run code in this Kotlin Multiplatform Academy lesson?
Yes. Every Kotlin Multiplatform Academy lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.
All lessons in this course
- A Sealed Result Type
- Catch Network & Parsing Errors
- Map Errors to UI Messages
- Retry & Offline Fallbacks