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Cross-platform · System design
Mobile System Design Blueprint
Evolve, migrate and operate mobile systems
Practise the decisions behind evolving, migrating, releasing and operating real mobile systems.
“great book, it’s exactly what we need in 2026, and it’s exactly as advertised”
20 decision chapters · 12 system scenarios · 50 exercises and answer key · PDF and EPUB
Mike Salari · Staff mobile engineer · 500+ technical interviews from the hiring side
From $199Buy on GumroadRead the free sample
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What is inside
Mobile System Design Blueprint in its own order: what each part teaches, so you can see whether it covers the round you have next.
- 01
The twenty decision chapters
Twenty chapters, each built around one architecture decision: authority, state ownership, offline, sync, idempotency, version skew, migrations, background work and budgets.
- 02
Releases, incidents and reversibility
Release trains, staged rollout, flags and kill switches, then incident response for the case where the installed binary cannot be patched quickly.
- 03
Platform and organisation chapters
Modularisation and CI cost, shared SDKs, platform teams, RFCs and governance, cross-platform ownership, and on-device AI treated as a versioned system.
- 04
Longitudinal architecture laboratories
Twelve scenarios, from payments and messaging to a super app and an AI assistant, each followed from a fast first version through evolution and incidents.
- 05
Fifty decision exercises
Fifty numbered exercises with an answer key, each asking for a concrete artefact for a system rather than a recited answer.
- 06
The Blueprint frameworks and case library
The reusable frameworks and scoring rubric behind the book, plus a case study library for architecture reviews.
Is it the right book for you?
Who gets the most from it, and when a different book is the better use of your time. The last list is as important as the first.
Use it when
- Your loop includes a dedicated mobile system design interview and you want practice beyond drawing boxes.
- You are preparing for a staff mobile system design interview where migration, mixed app versions and rollback get probed.
- You own an iOS or Android architecture that has to evolve while old binaries stay installed on user devices.
- You run architecture reviews and want a shared rubric and artefacts your team can score against.
- You lead a platform or shared SDK effort and need the ownership, governance and adoption side of the design.
Skip it when
- You still need platform fundamentals such as the basics of Swift, Kotlin or the UI frameworks.
- Your interview is in two days and you need last-minute answer triage, not a working lab.
- You want a book to read cover to cover; this one is built to be worked chapter by chapter with exercises.
- Your target role is junior or early mid-level, where the book's starting point is above what the round expects.
By level
- Senior
- The book's own path for senior engineers moving toward staff focuses on migration, mixed versions, operations and reversal, worked through scenarios S01 to S07.
- Lead
- Tech leads get a path through ownership boundaries, governance and shared foundations, with scenarios S08 to S11.
- Staff
- Staff readers use it as calibration: score a current design against the rubric, read the matching chapter, then score again.
- Architect
- Architects get a decision vocabulary and review artefacts for systems where the slowest-updating client sets the pace.
What a page looks like
Each decision chapter opens with a production failure story, states one durable principle, then works through the core decisions and failure modes before ending in an exercise and a required artefact. Scenarios are long labs that follow one system across evolution and incident stages. The exercises ask you to produce something for a system you work on.
The facts
- 20 decision chapters
- 12 system scenarios
- 50 exercises and answer key
- PDF and EPUB
- Light and dark editions
- Swift and Kotlin companion
- Last updated 5 Aug 2026
- Levels: senior, lead, staff, architect
What readers wrote
★★★★★
great book, it’s exactly what we need in 2026, and it’s exactly as advertised
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Questions buyers ask
Short answers about Mobile System Design Blueprint, from the book itself and the store page.
What format is it and how big is it?
The catalog lists 20 decision chapters, 12 system scenarios and 50 exercises with an answer key. It ships as PDF and EPUB, in light and dark editions, with a Swift and Kotlin companion.
Is this for iOS or Android engineers?
Both. The book covers iOS and Android system design, and the companion code comes in Swift and Kotlin.
Who is it for?
Senior engineers moving toward staff, tech leads, staff engineers and architects. The book gives each of those levels its own starting chapters and scenarios.
Can I see a sample first?
Yes. A free sample PDF is linked from the book page on salari.dev.
How much does it cost?
From $199, per the catalog.
How is it different from Altitude?
Altitude is a read-in-order curriculum on the whole system around the app: BFF, auth, cloud, distributed systems and the staff role. The Blueprint is a working lab for evolving, releasing and operating the mobile system itself, driven by scenarios, exercises and a scoring rubric.
Where is it sold?
On Gumroad, at the price shown there (From $199 when this page was built). Gumroad handles payment, the receipt and the download.