Consulting / SwiftUI & TCA Migration

SwiftUI & TCA Migration Consulting

UIKit-to-SwiftUI migrations, The Composable Architecture adoption, legacy codebase modernisation. I led the SwiftUI/TCA rewrite that took a medical app to 99.9% crash-free and a CES Innovation Award.

  • full UIKit-to-SwiftUI rewrites for production apps
  • TCA adoption with the judgment calls about reducer granularity and effects
  • rescuing migrations that stalled at 40% and got worse than before
  • Composable Architecture 2.0 migrations using the @Feature macro, spawned stores, and the new event/preference/trigger patterns
Recognition
App Store Best New Apps 2026 Product Hunt Product of the Day 2025 CES Best of Innovation 2021 CES Innovation Award 2021 Webby Honoree 2021 Google Material Design 2020
Credentials
Member of British Computer Society 2024 BEng (Hons) 2017 Apple WWDC Scholarship 2015

Tell me what you're working on. I reply within 48 hours.


"Vadim was instrumental to the success Epsy enjoyed on iOS, taking it from an idea on a Miro board to the highest rated and most downloaded app of its kind on the store."

James C. · Mobile Engineering Lead, Epsy

"We had a strict deadline, and Vadim managed to complete the job in time. He gave us meaningful feedback and suggested better approaches, not trying to blindly stick to our specification."

Founder · Pre-seed streaming service

"I can say with confidence that it will be difficult to find a better developer. Vadim is achievement-oriented, highly organized, with very good communication skills."

Alex Z. · Co-Founder, eda.so




Advisory
£110
per hour

Architecture reviews, hiring help, second opinions on that thing that's been bugging you.

Available now
Retainer
£4,000
per month

Priority support: review agency code, join architecture calls, catch problems before they ship.

Apr '26 May '26 Jun '26

Can you migrate us to SwiftUI without TCA?

Yes. About a third of my SwiftUI work is vanilla SwiftUI plus @Observable. TCA fits apps with substantial business logic and multi-person teams. For smaller or UI-focused apps, vanilla is cleaner and often faster.

Will our UIKit screens still work during the SwiftUI migration?

Yes. UIHostingController at the seams, UIViewRepresentable for UIKit views SwiftUI can't yet do cleanly, and a clear rule about who owns state at each boundary. I document this early so the team doesn't invent conflicting patterns.

We use MVVM / VIPER / Redux-style. Does TCA help?

Sometimes. TCA has specific strengths around testability, effect handling, and navigation modelling. If those are your current bottlenecks, the adoption cost is usually worth it. If your architecture problems are team-process problems, a new framework won't fix them.

Our UIKit migration stalled at 40%. What's the path out?

Two options. Either resume the gradual migration and finish module-by-module (months, but safer). Or commit to a full rewrite of the remaining 60% (shorter timeline, higher risk). Which one fits depends on how much of the migrated code is worth keeping and what's currently blocking the team.

Should we adopt TCA or stick with vanilla SwiftUI?

TCA fits apps with substantial business logic and multi-person teams. The structure pays for itself in testability and navigation modelling. Vanilla SwiftUI plus @Observable fits smaller apps, UI-focused products, and one-person teams. The adoption cost is only worth paying when the codebase has the state and effects that TCA is designed to organise.

Can you work alongside our existing iOS team during a migration?

Yes. Most of my migration work is pairing with an internal team: I architect and migrate the highest-risk modules, the team replicates the pattern on the rest. Leaves behind conventions the team can enforce in PR review after I'm out. 6-16 weeks depending on scope.

How quickly can you start?

Advisory calls can happen within days. For project work, I typically need 1-2 weeks notice to clear the calendar, though I keep some buffer for urgent firefighting. Check the availability badges above for current openings.

Do you work with early-stage startups?

Yes, from pre-seed to Series C and beyond. For very early teams, the advisory tier often makes more sense than project work: you get architecture guidance without committing to a large engagement before you've validated the product.

What's included in the day rate?

Everything: code, architecture decisions, code review, documentation, async Slack availability during working hours. No surprise add-ons. I bill for time spent working on your project, not for "thinking about it in the shower."

We're in a different timezone. Will that slow things down?

I'm currently in Vancouver (PST), with full overlap for North American teams. For UK and Europe, I'm online by their afternoon. For Gulf or APAC, we'd agree on overlap hours and handle the rest async. I've worked with teams from San Francisco to Dubai.


Migration strategythree different projects get called 'SwiftUI migration': net-new feature, screen-by-screen replacement, or full rewrite. Which one fits depends on team size, app age, and whether the domain model makes sense in the new architecture or needs redesigning.
TCA reducer granularitydeciding how much of a feature each reducer owns. A reducer that's too narrow forces more action plumbing between reducers. One that's too broad makes every test depend on the whole feature.
Effects vs Async/Awaitthe decision has moved over TCA versions. Picking the wrong one shows up later in every feature that handles side effects.
Shared state & @Sharedthe @Shared property wrapper changes how you model cross-feature data. Apps adopted pre-@Shared often have duplicated state that should consolidate.
When NOT to use TCAsmall apps, one-person teams, UI-heavy apps with little business logic. The adoption cost outweighs the gains when the codebase doesn't have enough shared state or effects to justify the structure.

Where I've worked CV · LinkedIn

Drobinin Limited Founder · 2025 - present 12+ apps from idea to App Store. Featured by Apple in EMEA & Americas.
LivaNova (NASDAQ: LIVN) Senior iOS · 2020-2025 Epsy, an epilepsy management app. Shipped inside an FDA-regulated medical-device company. HIPAA, CES Innovation Award.
Sphere (acquired by Twitter/X) Senior iOS · 2017-2020 Early Employee. $30M funding to acquisition.
VK.com iOS Consultant · 2016-2017 Authored & delivered an onsite course on iOS development.
ToBox Lead iOS · 2015-2016 Built team, MVVM architecture, full Swift rewrite.

Planning a SwiftUI migration?

Tell me what you're working on. I reply within 48 hours.

work@drobinin.com