Starling★3.5 (66)· London

Work with Swift (iOS) and Kotlin/Java (Android), native mobile security APIs and cryptography, and public cloud IaaS. You will design, build, and maintain security controls for the company’s Android and iOS mobile banking applications as part of the Cyber Security team.

Google★4.3 (6.2k)· London

Work with Java and Kotlin on Android display and power management frameworks across devices. Manage engineers as a Tech Lead Manager, ensuring stability and extensibility of critical display and power frameworks for the Android ecosystem.

Senior Software Engineer role at Everfox, working with modern C++ on cross-platform desktop (Linux, Windows) and mobile (Android, iOS) apps, plus Java/Kotlin, Swift/Objective-C, Qt, GitLab, Docker, Kubernetes, and Python. You will build and maintain the end-point software layer for the Hardsec product line’s secure browsing and VDI solution, owning design, development, and delivery. You will also coordinate a small team of engineers and manage release planning across multi-platform shipped products.

Proton★5.0 (1)· London

You will work with Kotlin, Jetpack Compose, and an increasingly shared Rust core to build Android applications. You will join a product team working on Proton Drive, Payments, or Account, building privacy-first tools for millions of users.

Design, develop and maintain scalable web and mobile applications using React or React Native for the front-end and Java for backend services and APIs at EC Markets.

Work with Kotlin, Jetpack Compose, Android Jetpack components, Kotlin Coroutines, Flow/StateFlow, RxJava, Hilt, and KMM. As an Android Engineer on the Customer Experience team, you will help further the success of the ASOS Android app, which has over 5M active users worldwide.

Proton★5.0 (1)· London

You will work daily with C#, TypeScript, and Rust, also providing bindings for Swift and Kotlin, using tools like Grafana, Prometheus, Sentry, GitLab CI, and Playwright. The Drive Foundation team builds the SDK that powers Proton Drive, ensuring cross‑client consistency and serving as the backbone for the encrypted cloud storage service.

Rightmove★3.7 (31)· London

Java, Spring Boot, Elasticsearch, Kafka, Gradle, Hibernate, Couchbase, SQL, and Docker. You will build and improve microservices that power Rightmove’s iOS and Android apps, working in a cross-functional team.

You will work with Kotlin, Spring, React Native, TypeScript, PostgreSQL, AWS, Terraform, and Ansible to build backend features for a cross-border fintech mobile app that serves emerging markets. The role focuses on developing consumer-facing features end-to-end in a fast-growing engineering team.

Rightmove★3.7 (31)· London

NodeJS and Java (Spring Boot) on Google Cloud Platform. This role leads cross-functional product development teams building the technology customers use to list properties on Rightmove.

Depop★4.4 (61)· London

This Senior Backend Engineer role uses Scala (primary), TypeScript, Python, Play Framework, Kubernetes, PostgreSQL, DynamoDB, and Kafka. The Shipping Experience team builds and evolves the end-to-end shipping journey for buyers and sellers on Depop’s peer-to-peer circular fashion marketplace.

Works with SAST, DAST, SCA, Burp Suite, OWASP ZAP, Semgrep, Python, Java, Kotlin, Go, JavaScript, and CI/CD pipelines (GitHub Actions

Work with Kotlin (90%+) and Java, using Android Studio, Jetpack Compose, Coroutines/Flow, MVVM, Webviews, and modular architectures. You'll build and test major new features for the Guardian's award-winning Android app, while improving and maintaining existing functionality. You'll take a leadership role on projects and mentor other developers.

Proton★5.0 (1)· London

Build the Proton Drive Linux client from scratch using GTK+ or Qt, with Rust as a nice-to-have, and manage Git, CI/CD pipelines, and Linux packaging for Debian and Fedora. The Proton Drive team provides secure cloud storage and collaborative editing, and this greenfield project will create the first native Linux client.

Proton★5.0 (1)· London

Join Proton's Inbox Desktop team to rebuild the Proton Mail Desktop App, Mail Bridge and Export tool using a cross-platform Rust stack. You'll work with Golang, C++, Qt, JS, TypeScript, React, Electron and standard dev tools (Git, GitLab CI, Jira). You’ll take technical ownership of the Windows and Linux desktop clients within a cross-functional team of about 60 engineers.

Proton★5.0 (1)· London

You will work on iOS apps using Swift, Xcode, and Apple platforms, with a growing Rust-based logical core. You'll join a product team building privacy-first tools for Proton’s encrypted email, VPN, cloud storage, and password management services used by millions.

Proton★5.0 (1)· London

You will work with PHP/Symfony for backend services, React for frontend, Kotlin (Android) and Swift (iOS) for mobile, with a growing shared Rust codebase, on Kubernetes infrastructure. The Payments team builds and scales payment methods and client libraries to enable subscriptions across Proton’s encrypted email, VPN, Drive, Pass, and Calendar products. The team works closely with the Account and Finance teams and across all business units.

Proton★5.0 (1)· London

Engineering Directors at Proton set technical direction and work with PHP (Symfony), Rust, Python, Swift, Kotlin, Jetpack, Typescript, React, C#, SQL, Redis, MySQL, and Ceph across mobile, desktop, web, and backend platforms. They lead engineering for one of Proton’s existing or upcoming products—such as Proton Mail, VPN, Calendar, Drive, or Pass—which provide private, secure, open-source tools to over 100 million users. The role involves managing a team of managers and driving DevSecOps practices.

JD.COM★3.8 (53)· London

Develop and maintain the Joybuy Android eCommerce app using Kotlin, Java, Android frameworks, and third-party libraries. You will collaborate with product management and engineering teams to deliver user-centric solutions for European markets.

Starling Bank seeks Android engineers to develop their in-house digital banking app using Kotlin, MVVM, RxJava, Dagger, and Realm, with testing via Espresso and JUnit. The role involves building features, improving CI automations and tooling, and shipping code alongside cross-functional teams at a fully licensed UK digital bank. Engineers work in hybrid arrangements with at least one office day per week, reporting to a mobile lead.

You'll build production Android apps in Kotlin, integrating AI-powered features like LLM chat, vision, and voice through backend APIs while optimizing performance and reliability for mobile devices. BJAK is developing a proactive AI smart assistant for everyday users focused on multi-step workflows, persistent context, and real-world task completion. The role requires 3+ years Android experience with hands-on AI feature integration and strong async programming skills.

You'll build the iOS app for xAI's AI system designed to understand the universe and aid humanity in knowledge pursuit. Work with Swift, SwiftUI, UIKit, Combine, and optionally Rust, focusing on performance optimization, real-time AI model integration via REST/gRPC, and pixel-perfect UI design. You'll own features end-to-end in a small, flat-structured team prioritizing engineering excellence and speed.

You'll build Android mobile experiences for xAI's AI applications using Kotlin, Jetpack Compose, and reactive programming. You'll work on a small team creating cutting-edge AI products that deliver user impact, with opportunities to use Rust for backend integration. Strong product sense, ownership, and architectural expertise in large production apps are essential.

Spotify★4.1 (116)· London

You'll design and build C++ integration layers for Spotify's TV playback, working with native media frameworks like AVPlayer and ExoPlayer on a Rust runtime. The Native Playback team owns critical systems including buffering, A/V synchronization, adaptive bitrate configuration, and rendering across TV devices, directly impacting millions of users' listening experience. You'll debug complex performance issues across application and OS layers, partner with platform teams, and improve test coverage and observability.

Depop★4.4 (61)· London

Staff Backend Engineer at Depop will work with Scala, Java, or TypeScript on AWS, GCP, or Azure, with event-driven architectures using Kafka. You'll lead technical design and architecture for the Payments and Fulfilment systems serving Depop's 35M-user circular fashion marketplace, partnering with product squads and engineering leaders while mentoring engineers and setting technical standards across these critical systems.