Manual QA Engineer

🏢 Summary: Role focused on owning and expanding automated test suites for Android and iOS SDKs within a high-scale mobile advertising platform. The position involves building mobile UI automation, integrating tests into CI/CD pipelines, and ensuring reliable test execution across real devices and environments. You will work closely with the Mobile SDK team to improve test coverage, stability, and deployment confidence. 🗂️ Requirements: 4+ years in automation engineering or 2+ years as SDET or developer, Strong JavaScript for test automation, Proficiency in Bash and Shell scripting, Experience with GitHub Actions for CI/CD, Experience with BrowserStack or similar real-device cloud platform, Proficiency with Maestro for mobile UI automation, Experience with Allure Reports, Experience with JIRA, Experience building automated test suites for Android and iOS 📃 Skills: JavaScript, Bash, Shell, GitHub, Actions, BrowserStack, Maestro, Allure, JIRA, Android, iOS, Firebase, Rust, TypeScript 🏢 Description: About LoopMe LoopMe is an AI company solving one of advertising's hardest problems: making brand advertising actually measurable — and making it perform. Our platform runs patented machine learning models across billions of consumer signals in real time, optimising campaigns toward outcomes like purchase intent, brand lift, and foot traffic rather than proxy metrics like clicks. The result is 2–5x better performance than industry benchmarks, at scale. We operate a high-load programmatic infrastructure — processing millions of ad requests per second with sub-200ms response times globally. This isn't a layer on top of someone else's stack; it's built from the ground up, in-house, by the team you'd be joining. Founded in 2012 and headquartered in London, we now have 400+ people across 19 cities and have sustained 40% revenue CAGR since 2018. The engineering problems here are real, the ownership is genuine, and the scale is significant. The opportunity You'll own test automation for LoopMe's Android and iOS SDKs, building and maintaining the suites that determine how fast and confidently we ship. Working alongside our existing automation engineer, you'll integrate deeply with the CI/CD pipeline using GitHub Actions, BrowserStack, and Maestro, and extend coverage as new SDK projects come into scope. This role sits within the Mobile SDK engineering team. What you'll do Build and maintain automated test suites for Android and iOS SDKs using JavaScript, Rust, and Bash/Shell scripting Develop mobile UI automation using Maestro across Android and iOS SDK projects Integrate automated tests into GitHub Actions CI/CD workflows for nightly smoke, regression, and Adapter Certification runs Own test execution and monitoring via BrowserStack App Automate, debugging environment-specific failures across devices and infrastructure Manage and publish test results through Allure Reports, surfacing findings to developers via JIRA and Slack Drive down nightly test run time by parallelising suites across multiple GitHub Actions runners Manage test builds via Firebase App Distribution for Android and iOS Leverage AI tools, including Claude, to accelerate test development and improve coverage and resilience What you'll bring Essential: 4+ years in automation engineering, or 2+ years as an SDET or developer Strong JavaScript skills applied to test automation Proficiency in Bash and Shell scripting, and GitHub Actions for CI/CD integration Experience with BrowserStack or a comparable real-device cloud platform Proficiency with Maestro for mobile UI automation, Allure Reports, and JIRA Nice to have: TypeScript familiarity TestRail or an equivalent test management system Charles Proxy for network traffic analysis Experience with AI-assisted test generation or self-healing frameworks Rust programming experience Adtech or programmatic advertising domain knowledge What we offer Hybrid working — flexible schedule 1 month of work-from-anywhere Annual performance bonus Multikafeteria (sport/culture card) LoopMe Gives Back Learning & development support

🏢 Summary: The offer is for a Java Backend Engineer to build and scale a high-load Data Management Platform processing billions of events daily in a real-time ad tech environment. The role focuses on developing and optimizing distributed data pipelines, microservices, and database schemas for performance and scalability. It involves working on complex backend systems supporting large-scale advertising auctions and audience targeting. 🗂️ Requirements: 2+ years of engineering experience, Proficiency in Java, Strong understanding of concurrency, Strong understanding of distributed systems, Experience with Spring Framework or similar IoC framework, Experience with JPA or other ORM framework, Strong knowledge of SQL, Experience with PostgreSQL or other modern RDBMS, Ability to work with large multi-module codebase 📃 Skills: Java, Spring, JPA, SQL, PostgreSQL, Spark, HBase, Kafka, Kubernetes, ORM, NoSQL 🏢 Description: We’re looking for a Java Backend Engineer to join LoopMe — a global AI-powered ad tech company redefining how brands connect with consumers across the open internet. In this role, you’ll help build and scale our Data Management Platform (DMP) — a massively distributed, high-throughput system processing billions of events daily , creating rich device and audience profiles, and exporting data segments to 50+ global partners and exchanges in real time. You’ll work on complex backend challenges around performance, scalability, data pipelines, and real-time processing , helping power the infrastructure behind large-scale advertising auctions and audience targeting. This is an opportunity to work on truly high-load systems , collaborate with experienced engineers, and have direct impact on a product used by some of the biggest players in the ad tech ecosystem. What you'll be doing: Developing features and optimizing performance for large-scale data pipelines (Spark jobs, HBase, Kafka) Designing and optimizing data schemas for relational and NoSQL databases Building microservice applications Core qualifications: 2+ years of engineering experience Proficiency in Java with a strong understanding of concurrency and distributed systems Experience with Spring Framework or similar IoC frameworks Experience with JPA or other ORM frameworks Strong knowledge of SQL and experience with modern RDBMS (PostgreSQL) Self-motivated, reliable, and comfortable working across a large multi-module codebase Additional experience we’d value: Experience with Apache Spark or other large-scale data processing frameworks Experience with HBase or other NoSQL/columnar stores Experience with Kubernetes Experience with Kafka Experience with AI/LLM integrations in backend services Benefits Flexible working schedule with a hybrid type of work Annual performance bonus One month of workation (you can work from any part of the world for one month) Multikafeteria

🏢 Summary: Backend Software Engineer role focused on building and scaling a high-traffic mobile advertising exchange that processes hundreds of thousands of real-time auction requests per second. The position involves full lifecycle development of distributed, low-latency microservices written in functional Scala and deployed to production. Engineers design, implement, test, and optimize backend systems for high availability and performance. 🗂️ Requirements: BS in Computer Science or related field, 6+ years of software engineering experience, 2+ years of Scala programming experience, Experience with Java or Python, Hands-on experience with microservices architecture, Experience building high-traffic, high-availability systems, Experience with Agile development, Ability to design, implement and test backend systems, Experience troubleshooting application and infrastructure issues, Experience writing unit tests 📃 Skills: Scala, Java, Python, Microservices, MongoDB, Bigtable, Aerospike, Kafka, PubSub, AWS, GCP, Git, Bitbucket, ProtocolBuffers, NoSQL 🏢 Description: LoopMe is the leading in-app monetization and programmatic advertising platform. We reach a mobile audience of over 900 million monthly unique users globally and process over 200 billion ad requests. The Chartboost SDK is the highest-integrated independent mobile ad SDK and through the Chartboost Exchange, Ad Network and other services, we empower mobile app developers to build businesses while connecting advertisers to highly engaged audiences. What we need: We are looking for a backend software engineer to join our exchange team and help us build the best advertising platform for mobile developers. You'll work on a system that processes hundreds of thousands of requests per second and conducts a real-time auction to find and deliver the most effective ads from our global partners. We trust our engineers to own this critical system and handle the full life cycle of feature development, from initial design all the way to shipping into production. Our system is written in functional Scala and has plenty of opportunities to flex your distributed, low-latency programming muscle, using technologies like mongoDB, protocol buffers and others. What you’ll be doing: Responsible for designing, implementing and testing the functionality of our Exchange product Work effectively with other engineers, system architects, and Operations teams to implement enhancements and issue resolutions Participate in technical discussions; come up with innovative ways to improve the product and process Troubleshoot issues with application, technologies, and infrastructure Continuously improve your technical knowledge Think creatively and work independently - collaborating with others as needed to maximize efficiency and throughput Deliver quality work on time while driving developer productivity across the organization You’re the type of engineer that appreciates clean code and has experience in writing unit tests to keep the utmost in code quality Qualifications: BS in Computer Science or related field 2+ years of Scala programming experience, along with experience in other programming languages such as java, or python. 6+ years of software engineering experience You have an understanding of microservices and hands-on experience implementing them You are experienced with software development in high-capacity, high-traffic, high-availability websites/systems You have experience working with Agile development The following experience would be a plus: Advertising technology experience Experience with Python or Java NoSQL databases (MongoDB, Bigtable, Aerospike etc) Distributed messaging services, like Kafka, PubSub Strong skills in Data Engineering Experience Managing Cloud infrastructure (AWS or GCP) Familiarity with Git and/or Bitbucket Benefits: International work environment Flexible working schedule with a hybrid working model (3 days from the office) Annual performance bonus (up to 8%) One month of workation (work from any location worldwide for one month) Multikafeteria

🏢 Summary: Backend Software Engineer role focused on building and optimizing a high-traffic mobile advertising exchange platform processing hundreds of thousands of requests per second. The position involves designing, implementing, and testing core exchange functionality, including migrating systems from Scala to Java. Engineers own the full development lifecycle in a distributed, low-latency environment. 🗂️ Requirements: BS in Computer Science or related field, 6+ years of software engineering experience, 1+ years of Scala programming experience, 2+ years of Java programming experience, Experience with microservices architecture, Experience with high-traffic, high-availability systems, Experience working in Agile environment, Experience writing unit tests 📃 Skills: Scala, Java, MongoDB, Bigtable, Aerospike, Kafka, PubSub, Python, AWS, GCP, Git, Bitbucket, Microservices, ProtocolBuffers 🏢 Description: LoopMe is the leading in-app monetization and programmatic advertising platform. We reach a mobile audience of over 900 million monthly unique users globally and process over 200 billion ad requests. The Chartboost SDK is the highest-integrated independent mobile ad SDK, and through the Chartboost Exchange, Ad Network and other services, we empower mobile app developers to build businesses while connecting advertisers to highly engaged audiences. What we need We are looking for a backend software engineer to join our exchange team and help us build the best advertising platform for mobile developers. You'll work on a system that processes hundreds of thousands of requests per second and conducts a real-time auction to find and deliver the most effective ads from our global partners. We trust our engineers to own this critical system and handle the full life cycle of feature development, from initial design all the way to shipping into production. Our primary system is written in functional Scala and has plenty of opportunities to flex your distributed, low-latency programming muscle, using technologies like MongoDB, protocol buffers and others. We’re planning on moving away from Scala to Java over the next few years, so be prepared to help us with that transition. What you’ll be doing Responsible for design, implementation and testing the functionality of our Exchange product Help translate our advertising exchange from Scala to Java Work effectively with other engineers, system architects, and Operations teams to implement enhancements and issue resolutions Participate in technical discussions; come up with innovative ways to improve the product and process Troubleshoot issues with the application, technologies, and infrastructure Continuously improve your technical knowledge Think creatively and work independently - collaborating with others as needed to maximize efficiency and throughput Deliver quality work on time while driving developer productivity across the organization You’re the type of engineer who appreciates clean code and has experience in writing unit tests to keep the utmost in code quality Who you are BS in Computer Science or related field 1+ years of Scala programming experience 2+ years of Java programming experience 6+ years of software engineering experience You have an understanding of microservices and hands-on experience implementing them You are experienced with software development in high-capacity, high-traffic, high-availability websites/systems You have experience working with Agile development The following experience would be a plus: Advertising technology experience Experience with Python or Java NoSQL databases (MongoDB, Bigtable, Aerospike, etc.) Distributed messaging services, like Kafka, PubSub Strong skills in Data Engineering Experience Managing Cloud infrastructure (AWS or GCP) Familiarity with Git and/or Bitbucket Benefits: International work environment Flexible working schedule with a hybrid working model (3 days from the office) Annual performance bonus (up to 8%) One month of workation (work from any location worldwide for one month) Multikafeteria

🏢 Summary: Full-stack engineering role focused on building and shipping production AI-powered features that automate logistics billing and payments. The position involves working across frontend, backend, and infrastructure to deliver scalable, high-quality solutions in a fast-paced early-stage environment. Engineers collaborate cross-functionally and leverage modern AI tools to accelerate development and impact core product decisions. 🗂️ Requirements: Minimum 2 years of software engineering experience, Experience with TypeScript, Experience with React, Experience with Node.js, Experience with GraphQL, Experience shipping products end-to-end in early-stage environments, Ability to work across frontend, backend, and infrastructure layers, Willingness to work onsite in SF or Chicago three days per week 📃 Skills: TypeScript, React, Node.js, GraphQL, Relay, Prisma, NestJS, PostgreSQL, Kafka, Redis, Elasticsearch, AWS, CDK, Fargate, ECS, Vite, AntDesign 🏢 Description: About Loop Loop is the data platform for the global supply chain. Logistics runs on messy, unstructured data—trapped in PDFs, emails, and legacy systems. We use AI to structure this chaos, creating a "source of truth" that automates payments and audits for the Fortune 100. We are building the financial nervous system for a $100 trillion physical economy. Our technology ensures freight moves efficiently and carriers get paid instantly. Backed by Founders Fund, Index Ventures and 8VC, we are scaling rapidly. We are looking for engineers ready to deploy production AI that powers the physical economy. About YouAs a full-stack engineer, you will work closely with founders and customers to understand and solve their logistics billing and payment pain points. You will help define the product and ship features that directly impact our customers. You will face and solve many complex technical challenges while you receive guidance and feedback from the team. You will shape the Loop DNA and define how we grow as a company. Responsibilities Work cross-functionally with product, design, and sales to understand requirements and ship thoughtful solutions. Write high-quality code optimized for extensibility. Engage in code reviews to maintain a high bar of engineering excellence. Lead discussions and documentation to communicate and arrive at the best technical design. Work across different component boundaries, from frontend to backend, and even infrastructure layers. Adopt AI technologies such as Cursor/Codex/Claude to accelerate software development and champion adoption of AI tools across the organization for increased productivity. Promote better practices and share technical knowledge across the team. Help grow Loop through deliberate feedback on product, process, and culture. Qualifications Willing to work in the SF or Chicago office three days a week Two years of software engineering experience. Experience with TypeScript and tools such as GraphQL, Relay, React, and Node.js. Experience working at early-stage companies where you shipped products end-to-end and wore many hats. Under the Hood Infrastructure: AWS, CDK, Fargate ECS Backend: TypeScript, Node.js, Prisma, NestJS, PostgreSQL, Kafka, Redis, Elasticsearch, GraphQL Frontend: TypeScript, React, Relay, Ant Design, Vite, GraphQL Compensation Base pay 150k+ per year Benefits & Perks Premium Medical, Dental, and Vision Insurance plans Insurance premiums covered 100% for you Unlimited PTO Fireside chats with industry leading keynote speakers Generous professional development budget to feed your curiosity Physical and Mental fitness subsidies for yoga, meditation, gym, or ski memberships Why you should join Loop? #LI-LOOP

🏢 Summary: Senior Java Backend Engineer role focused on building and optimizing a high-load ad-serving system processing over 5 million requests per second with strict latency goals. The position involves designing critical-path components, implementing architectural improvements, and enhancing performance in a real-time bidding platform. The role emphasizes scalability, low-latency optimization, and distributed systems engineering in a microservices environment. 🗂️ Requirements: 5+ years backend engineering experience, Strong Java proficiency, Experience with Spring or Spring Boot, Hands-on SQL experience, Experience with PostgreSQL or other relational databases, Knowledge of microservices architecture, Proficiency with Linux shell, Experience with Docker 📃 Skills: Java, Spring, SpringBoot, SQL, PostgreSQL, Linux, Docker, gRPC, ProtocolBuffers, Reactor, WebFlux, Kafka, Kubernetes, JFR, async-profiler, JVM, Testcontainers, ClickHouse, Aerospike, Redis, Micrometer, Prometheus, Grafana 🏢 Description: Are you eager to work with advanced technologies and build high-performance applications capable of processing over 5 million requests per second? If yes, we have an ideal opportunity for you at LoopMe. We are a team of experienced engineers developing and supporting real-time bidding platforms for global advertisers. You will work daily with talented engineers, using technologies such as Java, Spring Boot, gRPC, Project Reactor, Kafka, ClickHouse, PostgreSQL, Aerospike, and Redis. Your main focus will be on enhancing performance, optimizing cloud infrastructure, and developing innovative features across our product range. Join us in our mission to expand the limits of possibilities in the advertising industry! We are seeking a Senior Java Backend Engineer to join our Marketplace team and help develop our high-load ad-serving system, which can process more than 5 million requests per second with a 200ms response time. What you’ll be doing Designing and tuning hot-path components for the ad-serving critical path—such as throttling, rate limiting, targeting indexes, and DSP adapters. Implementing architectural changes across services — including RTB request lifecycle, deals targeting, and multi-impression-key processing. Creating gRPC APIs and Protocol Buffers schemas to facilitate cross-team integrations. Profiling and minimizing CPU usage and allocations to achieve strict p99 latency goals. Strengthening the system architecture to guarantee smooth operation during peak load times. Integrating advanced targeting algorithms into the main ad delivery process. Collaborating closely with multiple teams to provide services and data for our solutions. Core qualifications Over five years of experience in backend engineering. Solid understanding of Java and Spring / Spring Boot. Hands-on experience with SQL and familiarity with PostgreSQL or other relational databases. Strong knowledge of microservices architecture and its best practices. Proficient in Linux shell and Docker. Additional experience we’d value Concurrency in Java includes java.util.concurrent, CompletableFuture, lock-free data structures, virtual threads / Project Loom, and Reactor schedulers. gRPC and Protocol Buffers Project Reactor / Spring WebFlux Kafka Kubernetes Experience in managing high-QPS services, including profiling with JFR and async-profiler, GC tuning, and JVM internals understanding. Robust testing culture with unit tests, functional tests, and Testcontainers. Extra pluses AdTech / RTB domain expertise — OpenRTB, DSP/SSP, IVT, deals, cookie-sync, ads.txt, schain Performance engineering on critical paths — utilizing fastutil / Eclipse Collections, creating allocation-aware code, and optimizing for JIT awareness. Distributed systems experience includes rate-limiting algorithms such as token bucket, fixed and slidingwindow, as well as back-pressure, circuit breakers, sharding, and consistent hashing. Observability tools include Micrometer, Prometheus, Grafana, and structured logging. Full responsibility for managing multi-week epics across multiple teams. Experience with analytical or in-memory databases such as ClickHouse, Aerospike, Redis. Benefits Flexible working schedule with a hybrid type of work Annual performance bonus One month of workation (you can work from any part of the world for one month) Multikafeteria

🏢 Summary: Full-time on-site role for an experienced Manual QA Tester responsible for end-to-end testing of Flutter-based mobile applications on iOS and Android. The position focuses on ensuring quality, usability, and reliability, including testing of device-connected and hardware-integrated solutions. The role involves close collaboration with developers and active use of AI tools to enhance QA workflows. 🗂️ Requirements: Minimum 5 years of manual testing of mobile applications, Strong knowledge of iOS and Android platforms, Experience testing Flutter-based applications, Experience with IoT or device-connected solutions, Commercial use of AI tools in QA workflows, Experience with hardware setups, sensors, or measurement devices, Understanding of system performance and diagnostics, Experience with complex and non-standard testing environments, Ability to track and document bugs in Jira or Linear, English proficiency at minimum B2 level 📃 Skills: Flutter, iOS, Android, IoT, ChatGPT, Claude, Perplexity, Jira, Linear, Postman, Charles, Proxyman, Dart, ISTQB 🏢 Description: Quality Tester (Mobile Apps) – Professional experience with AI tools required Location: Wrocław, Poland Work model: Full-time, on-site About the Role We are looking for an experienced Manual QA Tester to join a team developing modern mobile applications in Flutter. This role is ideal for someone who combines strong testing expertise with a proactive mindset and enjoys working closely with developers in a fast-paced product environment. You will play a key role in ensuring application quality, usability, and reliability across mobile platforms. Key Responsibilities Perform end-to-end manual testing of mobile applications on iOS and Android Identify, document, and track bugs using tools such as Jira or Linear Create and improve test scenarios, reports, and documentation with the support of AI tools Collaborate with developers and product teams to validate fixes and improve release quality Verify UI consistency, responsiveness, and user experience across devices Participate in testing connected devices and hardware-related workflows Support validation, performance, and edge-case testing in lab-like environments Requirements Minimum 5 years of experience in manual testing of mobile applications Strong understanding of mobile platforms and Flutter-based applications Experience testing IoT or device-connected solutions Commercial experience with AI tools such as ChatGPT, Claude, or Perplexity in QA workflows Experience working with hardware setups, sensors, or measurement devices Technical understanding of system performance, diagnostics, and component validation Ability to work with complex testing scenarios and non-standard environments Good communication skills in English (minimum B2) High attention to detail and strong analytical thinking Nice to Have Familiarity with tools like Postman, Charles Proxy, or Proxyman Basic understanding of Flutter or Dart ISTQB certification What We Offer Opportunity to work on innovative mobile products Access to modern AI tools supporting daily work Collaborative environment focused on knowledge sharing and mentoring Comfortable office space with additional amenities

🏢 Summary: Leadership role responsible for owning and delivering high-quality mobile SDKs across Android and iOS, ensuring reliable releases, data integrity, and compliance while aligning engineering execution with business needs. The role combines hands-on technical oversight with team management, focusing on SDK stability, telemetry accuracy, and scalable third-party integrations. Success is measured by predictable releases, strong data quality, and effective adoption of AI-augmented engineering workflows. 🗂️ Requirements: 8+ years of mobile engineering experience, Leadership experience managing mobile engineers, Strong production experience in Android and iOS ecosystems, Deep expertise in at least one of Android or iOS, Strong SDK development experience including third-party integrations, Strong SQL proficiency, Experience with Python for data analysis, Experience with Git-based workflows and CI/CD pipelines, Experience with mobile observability and crash reporting tools, Understanding of telemetry and schema change management, Knowledge of networking fundamentals (TCP, UDP, QUIC, latency, TTFB), Experience with privacy and compliance requirements (GDPR, CCPA/CPRA, App Store, Google Play), Experience with experiment design and release validation practices, Degree in Computer Science, Software Engineering or equivalent experience 📃 Skills: Kotlin, Swift, Android, iOS, SQL, Python, Git, CI/CD, GitHub, Sentry, Firebase, Crashlytics, TCP, UDP, QUIC, GDPR, CCPA, CPRA 🏢 Description: How You Will Make an Impact You will be the clear, trusted owner for all things mobile at Opensignal, leading our iOS and Android SDK teams to deliver high-quality software that powers critical data products. You will align external business needs with engineering execution, ensure predictable releases, and protect data continuity and quality across first-party and third-party integrations. Our products rely on our ability to measure network performance accurately and consistently from our mobile apps and SDKs. Evolving our platform in step with business requirements and operating system changes is a critical success factor for this role. You will also help the team adopt AI in a pragmatic, safe, and outcomes-focused way, improving engineering velocity without compromising quality, privacy, or data integrity. Your impact will be measured by reliable on-time releases, stable SDK behavior in partner apps, strong stakeholder confidence, and zero major data outages or data perturbations. Early success includes smooth onboarding and delivery of new platform support (including Android 17 and upcoming iOS releases) without regression to data quality, alongside clear progress in AI-augmented engineering workflows and platform evolution that keeps pace with product needs. Primary Responsibilities Lead and directly manage the mobile engineering organization (currently 3 Android and 2 iOS engineers), including delivery planning, performance, coaching, and hiring support as needed. Serve as the primary cross-functional point of contact for mobile engineering with business, product, and data partnership stakeholders. Own end-to-end mobile release lifecycle management for our SDKs and related apps, ensuring high release quality and predictable delivery. Drive execution across first-party integrations (Opensignal app, Meteor app, ONX Connect) and third-party partner integrations that run our SDK at scale. Establish and enforce strong data-change discipline so SDK changes do not unintentionally alter critical metrics, schemas, or downstream product behavior. Lead experiment rollout and validation practices (feature flags, quality checks, and post-release verification) to confirm behavior changes as expected. Maintain compliance and policy alignment across privacy and platform requirements, including GDPR, CCPA/CPRA, Apple App Store, and Google Play policies. Drive pragmatic adoption of AI-augmented workflows across coding, QA, and data analysis, with clear guardrails for safety, privacy, security, and verification. Stay hands-on where valuable (technical reviews, architecture decisions, and targeted implementation support), while operating primarily as a manager and delivery owner. Knowledge & Skill Typically 8+ years of experience in mobile engineering, including meaningful leadership experience managing engineers and cross-functional delivery; equivalent depth of experience from non-linear career paths is also valued. Strong production experience across Android and iOS ecosystems, with deep expertise in at least one platform and demonstrated leadership capability across both. Strong SDK development experience (not only app development), including integration and maintenance in third-party applications. Strong data literacy, including SQL proficiency, ability to work with Python for analysis, and practical experience in data quality monitoring. Experience with experiment design and validation in software releases, especially where data integrity is business-critical. Strong understanding of telemetry/schema change management and the downstream impact of data contract changes. Solid networking fundamentals and practical experience relevant to mobile measurement use cases (for example TCP/UDP/QUIC behavior, packet flow timing, latency, and time-to-first-byte concepts). Demonstrated ability to communicate clearly with technical and non-technical stakeholders and translate business needs into execution plans. Experience operating within privacy, compliance, and platform-policy constraints for mobile SDKs. Proactive, curious mindset toward AI and modern engineering practices, with demonstrated judgment in adopting new tooling responsibly. We recognize that excellent candidates may not match every listed qualification exactly. If this role aligns with your strengths and experience, we encourage you to apply. Tools & Education Required: production experience with Kotlin and Swift. Required: experience with Git-based development workflows and CI/CD release pipelines (We use Github Actions). Required: experience with observability and crash tooling used in mobile environments (for example Sentry, Firebase, Crashlytics). Required: strong SQL proficiency. Preferred: Python for data analysis and validation workflows. Preferred: experience with feature flag rollouts, emulator/device testing strategies, and release validation frameworks. Preferred: experience with AI-assisted engineering tools/workflows and defining safe usage standards for teams. Education: degree in Computer Science, Software Engineering, or equivalent practical experience. About Us Opensignal is the leading global provider of independent insight and data into network experience and market performance. Our user-centric approach allows communication providers to constantly improve their network and maximise commercial performance. Leading analysts, investors and financial institutions place a high value on our independent analysis and we are regular contributors to their reports. Real network experience is our focus and ultimately that’s what influences customer choice. Our mission is to advance connectivity for all and here at Opensignal, the team is leading the industry in enabling operators to link their network experience and market performance in a way that has never before been possible. With offices in London, Boston Victoria, British Columbia, and Warsaw, and employees around the world, we are a truly global organization. We are an equal-opportunity employer dedicated to building an inclusive and diverse workforce. Benefits We believe we are stronger when we not only celebrate our many differences, values, and voices but include them in everyday practice. Having a diverse and inclusive culture is essential, which is why we offer a flexible approach to work-life balance, operating in a remote-hybrid way. We also offer an attractive range of additional benefits, including: 95% remotely - the team meets in the Warsaw office for 1 day/month Summer party and other social events Comprehensive private health care package for you and your family (dental care included) Multisport Card

🏢 Summary: Senior Mobile Automation Tester role focused on ensuring high-quality iOS and Android applications through automated and manual testing in a hybrid Krakow-based setup. The position emphasizes building and maintaining robust BDD-based automation frameworks and improving test coverage across mobile platforms. You will drive quality by designing test strategies, executing tests, and collaborating within Agile teams. 🗂️ Requirements: 5+ years of mobile test automation experience, Strong experience with Cucumber, Selenium, Appium, Proficiency in Java, Experience testing iOS and Android applications, Experience building and maintaining test frameworks, Experience with browser and mobile automation, Ability to create and execute test cases on real devices, Experience with CI/CD pipelines, Experience with GitHub, Experience with Jira, Understanding of APIs and client/server architecture, Experience working in Agile teams, Communicative English, Legal right to work in the EU 📃 Skills: Java, Cucumber, Selenium, Appium, iOS, Android, BDD, GitHub, Jira, CI/CD, APIs, Agile 🏢 Description: Empower mobile innovation — lead the future of seamless iOS and Android experiences! Krakow-based opportunity with hybrid work model (2 days in the office, 3 days remote). As a Senior Mobile Automation Tester – iOS/Android, BDD, Java , you will be working for our client, a forward-thinking technology company dedicated to delivering top-tier mobile solutions. Your expertise will help ensure high-quality releases of mobile applications by designing, developing, and maintaining automated tests, while also performing manual and exploratory testing to cover scenarios automation cannot address. Join a team at the forefront of mobile testing innovation and shape the future of user experiences. Your main responsibilities: Test new features and improvements across iOS and Android applications to ensure a superior user experience Design, develop, and maintain automated mobile tests using BDD (Cucumber), Java, Selenium, and Appium Contribute to the continuous improvement and stability of the automated test suite and supporting frameworks Perform manual and exploratory testing for scenarios not suitable for automation Create and maintain comprehensive test cases covering diverse devices, OS versions, and form factors Execute unit and functional tests on iOS and Android platforms Identify testing coverage gaps, define test strategies, and communicate potential risks early Run test plans, track testing progress, and generate reports on quality status Log, track, and retest defects using tools such as Jira Communicate progress, risks, and quality insights clearly to stakeholders You're ideal for this role if you have: At least 5 years of experience in mobile test automation and quality assurance Strong hands-on experience with building and maintaining test frameworks using Cucumber, Selenium, and Appium Proficient in Java with solid test engineering principles Experience automating tests for browsers and mobile devices (iOS and Android) Proven ability to develop effective test cases and execute them on real devices Familiarity with GitHub, CI/CD pipelines, and Jira for defect tracking and test execution Deep understanding of client/server interactions, APIs, and network behavior Experience testing applications with multiple user permissions and roles Comfortable working within Agile delivery teams Proactive, organized, and accountable approach to testing and quality assurance It is a strong plus if you have: Knowledge of accessibility testing and analytics validation for mobile apps Exposure to performance and reliability testing on mobile platforms Experience coordinating QA teams or leading testing projects Enthusiasm for mobile technology, devices, and operating systems Language Required for the role: Communicative English (strong command required) Eligibility for the role: Only candidates with an existing legal right to work in the European Union will be considered for this role. #MAKEYourCareerBETTER Interested? Apply now and include your CV (preferably in English) along with a statement confirming your consent to the processing and storage of your personal data.

🏢 Summary: Mobile Engineer role focused on building and maintaining a React Native application for field inspection and compliance management, featuring offline-first workflows, Bluetooth integrations, real-time synchronization, and secure data handling. The position involves full lifecycle mobile development, AI-assisted coding practices, and automated CI/CD in a collaborative, agile environment. The offer emphasizes performance, scalability, and high code quality for production-grade Android and iOS apps. 🗂️ Requirements: 3+ years experience with React Native for Android and iOS, Strong knowledge of JavaScript and TypeScript, Experience with Redux Saga and Redux Thunk, Experience with React Navigation, Experience with SQLite and encrypted storage, Experience integrating Firebase, Familiarity with Xcode and Gradle, Experience with CI/CD pipelines, Experience publishing apps to App Store and Google Play, Experience with Jest and React Native Testing Library, Use of AI coding tools (e.g. GitHub Copilot, Devin, Windsurf), Intermediate or higher English level 📃 Skills: ReactNative, JavaScript, TypeScript, ReduxSaga, ReduxThunk, ReactNavigation, SQLite, Firebase, Xcode, Gradle, GitHubActions, Fastlane, Jest, ReactNativeTestingLibrary, SonarQube, Appium, Bluetooth, NewRelic 🏢 Description: We are looking for a Mobile Engineer who is passionate about building reliable, user-focused applications used in real-world operational environments. You will work on a mobile platform for field inspection and compliance management in the food service and hospitality industry, contributing to features such as offline-first workflows, Bluetooth-connected sensor integrations, real-time data synchronization, and digital audit processes. This role offers the opportunity to work on meaningful technical decisions in a collaborative engineering environment focused on performance, usability, and scalability. The application includes capabilities such as encrypted local storage, cloud CRM synchronization, document signing, photo and file management, PDF generation, push notifications, and mobile monitoring tools for crash reporting and performance tracking. CI/CD processes are fully automated using GitHub Actions, including linting, testing, SonarQube analysis, and deployments to TestFlight and Google Play. You will join a cross-functional team consisting of an Engineering Manager, ADC, Tech Lead, Back-End Developers, Front-End Developer, and Mobile Developers, working together in an agile and collaborative setup. We follow a remote-first setup with no mandatory regular office visits for this position. From time to time, you may be invited to join in-person meetings in one of our offices (Warsaw, Lodz, Wroclaw, Gdansk, or Bialystok), for example for client visits or team reunions. Must have: 3+ years of experience in creating React Native mobile solutions for Android and iOS Strong communication and team player skills Solid knowledge of JavaScript, TypeScript, React Native, React Native components, Redux Saga, Redux Thunk , React navigation SQLite and Encrypted Storage Strong skills in creating flexible user interfaces and custom views Experience integrating Firebase Familiarity with native build tools: Xcode, Gradle Experience with CI/CD pipelines: GitHub Actions, Fastlane Experience publishing apps to the Apple App Store and Google Play Console Jest + React Native Testing Library for unit/integration Demonstrated AI-first mindset: regular, structured use of agentic AI tools such as GitHub Copilot, Devin, or Windsurf Written and spoken English at intermediate level or higher Nice to have: Experience with New Relic mobile monitoring and performance observability Knowledge of SonarQube Experience with Appium or other E2E mobile testing frameworks Experience with Bluetooth integrations or custom native modules Web development experience (React.js, Node.js) Proven use of AI for non-trivial tasks — feature scaffolding, refactoring, test generation, or workflow automation Your responsibilities Engineering and development of mobile using modern technology stack Applying an AI-first development approach using agentic coding tools in day-to-day work Taking part in full app development lifecycle and actively influencing all phases as well as UI/UX design considerations Close cooperation with our clients including daily standups/retros/refinements Ensuring code quality through unit testing, static analysis and peer code reviews Sharing knowledge and experience within the team and Mobile Division