Senior Mobile Engineer - Android (f/m/d)

Department: EPD

Location: Warsaw

Employment Type: FullTime

At Moss, we give finance professionals the power to automate their day-to-day and make forward-thinking decisions.

Our team and culture make us unique — we’re driven by impact and growth, where every one of us strives to learn and excel. Recognised by Sifted’s Rising 100 and LinkedIn's Top Startups, we’re here to help propel your career and together, make Moss a lasting success.

We are a fast-growing, AI-first startup looking for a Mobile Engineer to join our mobile team. We ship fast, value ownership and autonomy, and communicate in English.

The Mobile Team is responsible for building and maintaining our mobile applications, enabling Spenders to easily manage and submit expenses, and Admins to stay in control of company spending. We also own the backend-for-frontend service powering the mobile experience, as well as the full release process.

On a day-to-day basis, you’ll collaborate closely with designers, product managers, and engineers to bring new ideas to life and deliver intuitive, high-quality tools that help businesses simplify and automate their financial workflows.

Your responsibilities

• Development and maintenance of the Moss mobile applications based on product requirements

• Development and maintenance of backend services supporting mobile applications, in alignment with existing architecture and systems

• Contributing to the design and evolution of the Android mobile application architecture

• Supporting and executing mobile app releases via Google Play

About you

Must Have’s

• Strong proficiency in Kotlin

• Kotlin Coroutines & Flows & Jetpack Compose**

• Android Lifecycle - deep understanding of Activity/Fragment lifecycle, process death, configuration changes

• Clean Architecture - clear separation of layers (domain, data, presentation), use cases, repository pattern

• Familiarity with Google Play release process

• Knowledge of mobile testing strategies

• Hands-on experience using AI coding agents to accelerate development

• Critical review of AI-generated code - ability to catch regressions, architecture violations, hidden side effects, and subtle bugs in generated output

• Strong verbal and written communication skills in English

• Ability to articulate technical decisions, trade-offs, and blockers clearly

• Comfortable working autonomously with minimal hand-holding

Nice to Have’s

• Experience working in a startup environment (comfort with ambiguity, fast iteration)

• iOS development knowledge (Swift/SwiftUI) - ability to contribute to or review iOS codebase

• Spring Boot / backend development - supporting mobile backend services

• Experience with CI/CD pipelines

About Moss

Moss is a SaaS scale-up founded in Berlin, with a team of 300+ people from 50+ nationalities in 5 offices across Europe. 

Our ambition is bold: to power every SMB’s spend across Europe - fully digital, AI-driven, and seamlessly integrated for complete control. To date, over 5000 businesses in Germany, Netherlands and the UK use Moss’ leading spend management product, with modules such as corporate cards, accounts payables, employee cash reimbursements and procurement.

Moss has raised a total of €180 million in funding and is backed by the most renowned tech investors including Valar Ventures, Tiger Global, Global Founders Capital, Cherry Ventures and A-Star.

Be part of a culture that thrives on impact and speed, where you can take bold moves, learn fast and accomplish more. We’re a place where you can fast track your career - here's what else to expect:

• Top-of-market compensation package, including equity. 

• Our vibrant offices are at the heart of our culture, where in-person time fuels collaboration and connection over weekly breakfasts and Friday demos.

• Additional benefits include: 20 days “work from abroad”, 600EUR/GBP Learning & Development Budget, and other local benefits.

Unless stated otherwise, benefits apply to full-time positions (interns and working students receive a tailored package).

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