Senior Mobile Engineer (Swift and/or Kotlin)
Summary
Senior Mobile Engineer at Exerizon, a technology consulting firm, building and modernising native iOS (Swift) and/or Android (Kotlin) apps for banking, insurance and healthcare clients — high-traffic, security- and regulation-heavy apps involving mobile security, CI/CD, API integration and server-driven UI. Remote within Poland with a Warsaw office, B2B contract.
Exerizon is a fast-growing strategy and technology consulting firm founded by former senior leaders from global consulting and cloud organizations. We help current and future market leaders tackle their greatest challenges — from digital strategy and cloud transformation to data & AI platforms and application modernization. We redefined the traditional consulting model: we share risk with our clients through impact-based remuneration, and we share ownership with our people from day one.
We are looking for a Senior Mobile Engineer to build and modernise native mobile apps for our clients in banking, insurance and healthcare — on iOS (Swift), Android (Kotlin), or both. You will work on apps that are the client's primary customer channel: high traffic, strict security and regulatory requirements, and real consequences when a release goes wrong.
Benefits
- Real ownership of the apps you build and direct contact with client product owners — no ten-layer review pyramid
- Competitive compensation on B2B contract
- Annual training and certification budget
- Remote work model with access to a central Warsaw office
- A seat at the table in shaping a young firm: our mobile practice, engineering standards, hiring and culture
- 6+ years of native mobile development, including 3+ years in Swift (iOS) and/or Kotlin (Android); at least two apps shipped to production and maintained through multiple rele
- Deep knowledge of your platform — iOS: SwiftUI and UIKit, Swift Concurrency or Combine, Xcode toolchain; Android: Jetpack Compose, Kotlin Coroutines and Flow, Android Jetpack, Gradle — with a working understanding of the other platform
- Hands-on experience with mobile security in regulated environments: OAuth2 / OIDC and strong customer authentication flows, secure storage, certificate pinning, OWASP MASVS, and closing pen-test findings
- Solid testing and CI/CD practice: XCTest or JUnit, UI and snapshot tests, automated pipelines, code signing, store submission and release management
- Proven ability to own architecture decisions and refactor large legacy codebases safely, with measurable improvements in build time, crash rate or release cadence
- Experience designing or integrating a server-driven UI framework: component schemas, a client renderer, schema versioning and A/B-tested layouts; you know where SDUI pays off and where it hurts (offline, performance, accessibility)
- AI-driven development as part of your workflow: you use coding agents and copilots daily, understand their failure modes, and review AI-generated code to the same standard as your own
- Fluent in API integration: REST and GraphQL, OpenAPI contracts, and working with backend teams on API design
- Experience delivering apps in banking, insurance, fintech or healthcare, including PII handling and regulatory constraints (PSD2 / SCA, GDPR)
- Clear communication with non-engineers: you explain trade-offs to a product owner and estimate honestly
- Full professional fluency in Polish and English
- Nice to have:
- Mobile payments integration (Apple Pay, Google Pay, BLIK)
- Accessibility auditing experience (VoiceOver, TalkBack)
- Tech lead or team lead experience on a client-facing engagement
- Building your team's AI tooling: custom agents, MCP servers or codebase-specific skills and prompts
- Shipping an SDUI-based app at scale, or contributing to an open-source SDUI framework