Mobile Software Engineer – Lead Kotlin Multiplatform Migration

About the role

We are looking for a Mobile Software Engineer to lead the migration of our native iOS and Android applications into a unified Kotlin Multiplatform codebase. You will work closely with the Head of Tech in a fast‑growing climate‑tech startup that is tackling single‑use packaging waste.

Key responsibilities

• Design, develop and maintain consumer‑facing and point‑of‑sale mobile applications using Kotlin.
• Architect and execute the transition to a single Kotlin Multiplatform (KMP) codebase for both Android and iOS.
• Integrate lightweight web components with Apple Wallet and Google Wallet for container tracking.
• Collaborate with backend teams, contributing to PHP/Laravel services and occasional Python code for smart‑bin hardware.

Required profile

• 1–2 years of professional mobile engineering experience with production‑grade Kotlin.
• Strong native Android development background.
• Interest or hands‑on experience with Kotlin Multiplatform.
• Startup mindset – comfortable touching backend code and hardware integrations while delivering clean, production‑ready code.

Required skills

• Kotlin
• Android development
• Kotlin Multiplatform (KMP)
• iOS development (via KMP)
• PHP / Laravel
• Python
• Apple Wallet integration
• Google Wallet integration

What we offer

• High autonomy to lead the KMP migration.
• Equity options as an early‑stage team member.
• Opportunity to work with enterprise clients such as BT and NHS.
• London‑based office in a mission‑driven climate‑tech environment.