Kotlin Multiplatform Engineer (Senior or Staff)
About The Position
As a Kotlin Multiplatform Engineer at Cantina, you’ll be the architect of our shared-code strategy — building the foundation that powers our experiences across Android, iOS, and web from a single Kotlin codebase. You’ll work at the cutting edge of the KMP ecosystem, shipping production code to real users on multiple platforms, while keeping platform-specific layers feeling truly native. We’re looking for a Kotlin expert who has been in the trenches with KMP — someone who has wrestled with interop edge cases, navigated the wasm target, and shipped Compose Multiplatform UI that feels polished everywhere.
Requirements
- 8+ years of software engineering experience with deep, expert-level Kotlin — you know the language spec, not just the idioms.
- Real-world, production KMP experience: you’ve shipped KMP code that real users ran on Android, iOS, and/or wasm — not just toy projects or internal tools.
- Hands-on Compose Multiplatform experience: building shared UI across multiple targets with platform-specific adaptations.
- Experience with Koin Multiplatform for dependency injection across KMP targets in production codebases.
- Solid understanding of Kotlin/Native memory model, freezing, and interop with Obj-C/Swift APIs.
- Experience targeting Kotlin/Wasm and/or Kotlin/JS, including the Compose for Web stack.
- Fluency with multiplatform build tooling: Gradle multiplatform plugin, source sets, target configuration, and CI pipelines.
- Strong grasp of coroutines, Flow, and structured concurrency — understanding how they behave across targets.
- Ability to write readable, maintainable, thoroughly documented, and well-tested shared code.
Nice To Haves
- Experience with KMP libraries (Ktor, SQLDelight) in production environments.
- Contributions to the KMP/CMP open-source ecosystem or close familiarity with JetBrains’ roadmap.
Responsibilities
- Design and build shared KMP modules covering networking, data persistence, business logic, and domain models used across Android, iOS, and wasm targets.
- Ship production-grade Compose Multiplatform UIs that feel native and performant on Android, iOS, and web.
- Build optimized platform-specific targets — leveraging Swift/Obj-C interop for iOS and Kotlin/Wasm for web — to meet the performance and UX bar of each platform.
- Architect clean platform-expect/actual boundaries and maintain Kotlin/Native and Kotlin/JS interop layers.
- Set up and manage Koin Multiplatform for dependency injection across all targets, ensuring clean and testable module graphs.
- Collaborate with platform teams (iOS, Android, web) to align on shared APIs, versioning, and release cadences.
- Drive KMP best practices across the organization — tooling, testing strategies, CI/CD for multiplatform builds.
- Lead development of new AI and media-driven features within the shared codebase.
- Participate in architecture reviews and uphold high standards for shared module design and testability.
Benefits
- Competitive salary and generous company equity
- Medical, dental, and vision insurance – 99.99% of premiums covered by Cantina
- 42 days of paid time off, including: 15 PTO days, 10 sick days, 15 company holidays, 2 floating holidays
- Generous parental leave & fertility support
- 401(k) retirement savings plan
- Lifestyle spending account – $500/month to use however you’d like
- Complimentary lunch and snacks for in-office employees
- One Medical membership
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What This Job Offers
Job Type
Full-time
Career Level
Senior
Education Level
No Education Listed
