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From the hiring side

What decides a senior mobile interview.

Written by Mike Salari after 500+ technical interviews: the follow-up questions, the system design and architecture rounds, and the leveling that sets the offer.

An abstract note card with ruled lines labeled evidence, signal and level; one line is highlighted in gold and feeds into a single decision node.
iOS and Android · 12 min read

What I write in the debrief after a senior mobile interview

The notes behind a hiring decision, from the person who writes them, and what a candidate can do to end up in them.

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A timeline diagram of an interview: the first answer continues as a grey line while a follow-up branch splits off in gold and carries to the decision point.iOS and Android · 10 min read

The follow-up decides the senior mobile interview

An interviewer's view of the moment one fact changes, and why that moment carries the offer.

A stepped level ladder with scope rings widening from the senior step to a gold staff stepiOS and Android · 9 min read

Senior vs staff mobile interview: the signals that set level

The same correct answer can be scored at senior or at staff; the difference is scope, trade-off ownership and what you say you would measure.

Diagram of an actor box with two task timelines entering it; one timeline suspends at an await marked in gold while the actor's state changes underneath it.iOS · 13 min read

Swift concurrency interview questions where answers break

The six Swift concurrency questions senior and staff iOS loops keep asking, the answer that sounds right, and the follow-up that decides the score.

Module dependency tree on a dark background; the leaf modules at the bottom are ticked in gold and a gold band moves up toward the app target labeled Swift 6.iOS · 14 min read

Swift 6 strict concurrency migration: what breaks first and the fix

The order I migrate targets in, the six kinds of errors every existing iOS app hits, and the fix for each one, checked against the Swift 6.3 compiler.

A tree of coroutine jobs under viewModelScope with a gold cancellation signal reaching every child, beside a detached GlobalScope branch it never reaches.Android · 12 min read

Kotlin coroutines interview questions: where answers break

An interviewer's view of the coroutine and Flow questions in senior Android loops, and the follow-up that separates a memorized answer from a reasoned one.

Architecture diagram of a phone with a local database and an outbox queue, connected to a server by a dashed intermittent link, with the sync path drawn in goldAndroid · 12 min read

Android system design interview: offline sync at staff level

The offline notes app is the most common mobile design prompt in senior and staff Android loops, and the diagram is the easy part.

A module graph diagram: a tangle of crossing grey dependencies on the left, and on the right a clean layered graph where one boundary is drawn in gold and every arrow points inward toward an API module.iOS and Android · 11 min read

Mobile architecture interviews: modularization that holds up

An interviewer's view of the architecture round, where "modularize everything" is the answer that ends the conversation early.

A repository file tree drawn in grey lines on black, with a numbered gold path running from the README to the decisions, then the tests, then the UI files.iOS and Android · 12 min read

How senior mobile take-home assignments are actually graded

A reviewer's view of the senior take-home, where the README is read before the code and the most patterns rarely wins.

A gold cancellation signal travels down a coroutine, is caught by a box labelled runCatching, and the path beyond it keeps going in gold where it should have stopped.Android · 11 min read

runCatching swallows cancellation, and code review rarely catches it

A reproducible write-up of the runCatching CancellationException bug: the test that proves it, the shapes it hides in, and what each fix costs you.

A strip of fourteen day cells that grow in intensity from left to right, with the mock loop day and the interview day marked in goldiOS and Android · 9 min read

A 14-day prep plan for a senior iOS or Android interview

Two weeks is enough if you spend them on the one gap that would cost you the point, not on reading more answers.