Alma
Alma Pay
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iOSSwift
Apple platform consulting
Senior iOS Consultant
Senior judgment for iOS architecture reviews, technical audits, modernization decisions and team mentoring — when the engineers are in place but the answer is not.
Discuss the engagement Explore the expertise- 2008
- Building digital products since
- 40+
- Apps shipped
- 400M+
- Cumulative downloads
Clément Sauvage · Bits’n Coffee
Senior judgment when the team has capacity, but not the answer.
Clément Sauvage is a senior iOS consultant and product engineer who helps engineering teams make the technical decisions that shape native Apple products: architecture, modernization, code quality, delivery and team capability. He has built Apple products since 2008 and remains hands-on in Swift, SwiftUI and UIKit. Experience as both lead developer and CTO keeps every recommendation connected to its implementation cost.
Companies bring him in when they have the engineers but not the answer: whether to rewrite or modernize, how to introduce SwiftUI into a mature UIKit app, why delivery has slowed, or what a codebase is worth before further investment. Based in France, he works directly with CTOs, engineering leaders and product teams in English and French across Europe, the United Kingdom, the United States and Switzerland. Larger or multidisciplinary delivery can continue through Bits’n Coffee, the product engineering studio he founded and leads.
When to bring me in
Where an experienced diagnosis changes the outcome.
The role brings senior judgment to a team that already has capacity: understand what exists, decide what should change and in what order, then make sure the team can carry the change.
What is the team facing?
You need an independent view of the codebase
Review architecture, state and navigation, data, dependencies, concurrency, testing and release practices before a major investment, hiring decision or team handover.
The rewrite-or-modernize decision is blocking the roadmap
Separate foundations that actively constrain the product from working code that should remain, then sequence targeted modernization without freezing delivery.
Your iOS team needs a senior counterpart
Add architecture review, mentoring, code-level support and decision facilitation while strengthening the team instead of creating dependency on an external expert.
A difficult Apple-platform problem has stalled delivery
Investigate a production-only crash, performance issue, blocked migration or App Store rejection, then turn the diagnosis into a practical path forward.
What the role covers
Architecture, modernization and team capability.
The engagement can be a scoped audit, a recurring presence alongside the team or a short intervention on one consequential question.
Architecture review and technical audit
A structured assessment of architecture, state, navigation, data, dependencies, concurrency, testing, builds and releases, ending with a sequenced plan rather than a textbook gap list.
Rewrite or modernize
Decide what is sound, what creates friction and what is risky, then improve the foundations in an order that lets the product continue to ship.
SwiftUI and Swift concurrency adoption
Plan UIKit interoperability, incremental SwiftUI adoption and strict-concurrency migration around real product and team constraints instead of platform fashion.
Team mentoring and capability
Combine focused workshops with code reviews, pair programming and design discussions so the team can make better Apple-platform decisions after the engagement.
Hands-on investigation and reference code
Use a prototype, proof of concept, production investigation or reference implementation when working code is the fastest way to settle the decision and unblock the team.
Relevant experience
Judgment tested on products in production.
Selected Apple-platform engagements spanning long-running partnerships, financial products and native experiences at scale.
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iOSSwift
How I work
Inspect the system. Make the trade-off. Transfer the reasoning.
There is no fixed consulting package. The format follows the problem, but every important recommendation should be understandable, actionable and owned by the team.
- 01Frame
Define the decision before reviewing the code
Clarify the product, team, roadmap, evidence available and cost of being wrong so the investigation answers a useful question.
- 02Inspect
Follow the product through the system
Review code, architecture, delivery and team practice together, because most persistent iOS problems live across those boundaries.
- 03Decide
Recommend a sequence, not an idealized destination
Make trade-offs explicit, rank work by impact and risk, and identify the next changes the team can ship without losing the roadmap.
- 04Transfer
Leave reasoning the team can inherit
Document the important decisions, demonstrate patterns in code when useful and give the team enough context to revisit them as constraints change.
Frequently asked questions
The decision before the engagement.
The scope, format and expected decision should be explicit before the review begins.
What is the difference between an iOS consultant and an iOS developer?
If the main need is something built, you need a developer. If the engineers are already in place and the missing piece is diagnosis, direction or experience, you need a consultant. Many engagements include both; the distinction is where the centre of gravity sits.
Should we rewrite our iOS app or modernize it?
Modernize in most cases. A full rewrite is rarely necessary and often takes longer than planned. The first step is to identify what is sound, what creates friction and what actively prevents the product from evolving, then sequence targeted changes while delivery continues.
Should an existing UIKit app move to SwiftUI?
Only where SwiftUI solves a real product, engineering or team problem. UIKit does not become debt because SwiftUI exists. For many mature apps, the right answer is incremental adoption with explicit interoperability and stable UIKit left in place.
What does an iOS technical audit include?
Architecture, state and navigation, data, dependencies, concurrency, testing, build and release, plus the fit between the code and the product’s constraints. The deliverable is a diagnosis and sequenced plan: what to keep, fix or replace, and in what order.
How long does an iOS consulting engagement last?
A scoped audit can take days to a few weeks. Supporting a migration may mean one recurring day a week over several months. A narrow production or App Store problem can be a short intervention. The format is proposed after the situation is understood.
Do you write code as a consultant?
Yes, when code is the fastest way to unblock the team: a prototype, proof of concept, reference implementation, production investigation or pair programming on the difficult part. It is not used as a substitute for the team’s own work.
How do coding agents fit into the engagement?
Agents can accelerate implementation when they operate inside an architecture a responsible engineer defines, reviews and owns. Clément can help teams establish that discipline without confusing AI-assisted engineering with unsupervised delivery.
Do you work with companies outside France?
Yes. Clément is based in France, works in English and French, and takes engagements across Europe, the United Kingdom, the United States and Switzerland. Remote collaboration is standard, with on-site sessions where useful.
Tell me what the team is facing.
I’ll tell you how I would approach it.
Share the product, the team, the codebase as it stands and the decision you are trying to make. I’ll personally review the context and explain the consulting format that would create the most useful outcome.
Discuss the engagement