For companies
Senior mobile delivery, without the ramp-up
I'm David Cruz Anaya, an independent senior mobile engineer. I help companies modernise Android apps, adopt Kotlin Multiplatform, and add native Rust where it pays off, with 12+ years shipping apps used by millions at Sky, MGM, WWE and BritBox.
Services
Where I help
Primary service
Android app modernisation
- The problem
- An ageing Android codebase is slow to change, hard to test, and expensive to keep alive.
- When it fits
- Legacy Java or XML, a fragile architecture, slow releases, or rising crash and regression rates.
- What I deliver
- A prioritised migration to Kotlin and Jetpack Compose, a modular architecture, a real test and CI/CD setup, and a plan your team can follow after I leave.
Strategic service
Kotlin Multiplatform adoption
- The problem
- Android and iOS drift apart because the same business logic is written, and fixed, twice.
- When it fits
- You want a shared core across platforms without pausing the roadmap or rewriting the apps.
- What I deliver
- An incremental migration proven on one feature first, a shared module structure, and a team able to keep going on their own.
Advanced specialisation
Native Rust for performance-critical components
- The problem
- A latency- or CPU-bound problem the platform SDKs handle poorly, needed identically on Android and iOS.
- When it fits
- Real-time audio, media processing, cryptography or parsing, where a native layer is genuinely justified. Not by default, and I will tell you when it is not.
- What I deliver
- A Rust module with a clean Kotlin- and Swift-facing API, shared across platforms, with tests and benchmarks.
Additional modality
Embedded senior mobile delivery
- The problem
- You need senior mobile capacity now, not a three-month hiring process.
- When it fits
- A team that needs to ship, raise its engineering bar, and level up while doing it.
- What I deliver
- I embed as a senior engineer or technical lead: I write the hard parts, make architecture decisions stick, and mentor the team that stays.
How I work
Clear scope, senior work, clean hand-over
- 01
Scope
A short, paid discovery to map the codebase, the constraints, and what "done" means. You get a written plan whether or not we continue.
- 02
Deliver
Fixed-scope project or embedded senior engineer, whichever fits. Senior work end to end: I write the hard parts myself and keep your team in the loop.
- 03
Hand over
Documentation, decisions, and enough context transfer that your team owns the result. No lock-in, no dependency on me to keep it running.
Proof
Shipped, not theoretical
The work page walks through real cases: streaming apps for Sky, WWE and BritBox, a regulated sportsbook and casino for BetMGM, and Klarinet, a low-latency audio SDK for Kotlin Multiplatform. Each one is written up as a problem, the engineering pressure, and the decisions behind it.
Read the case studiesHave a mobile problem worth solving?
Tell me what you're building and where it's stuck. If I'm the right fit, we'll scope it. If I'm not, I'll say so.
Discuss your mobile projectFAQ
Frequently Asked Questions
Do you work remotely?
Yes. I work with companies remotely from London and can overlap with European and US-East hours. On-site visits are possible for kick-off or key milestones.
Do you take fixed-scope projects or ongoing work?
Both. A modernisation or KMP migration usually runs as a fixed-scope project; senior delivery and team support usually run as an embedded engagement. We agree the shape during scoping.
When does native Rust actually make sense?
When you have a latency- or CPU-bound problem that the platform SDKs handle poorly, such as real-time audio, media processing, or cryptography, and you want one implementation shared across Android and iOS. If it does not earn its place, I will tell you.
What kinds of apps have you shipped?
Consumer apps used by millions, including streaming (Sky Go, WWE, BritBox, My5) and regulated betting and casino (BetMGM), plus multiplatform libraries. See the work page for cases.