Mozilla seeks a Senior Software Engineer for the Engineering Workflow and CI team to improve Firefox development workflows, reduce test/debug time, integrate automation, and provide dashboards and data-driven insights. The role requires proven Python development experience (services/frameworks), frontend/JavaScript proficiency, familiarity with cloud services (GCP/AWS), REST, databases/SQL, and CI/CD systems (e.g., GitHub Actions, CircleCI). Responsibilities include collaborating across distributed teams, mentoring, code review, and working cross-platform.

Join the MediaWiki Platform team to design, improve, and maintain core MediaWiki components and shared platform capabilities (authentication, caching, rate limiting). The role emphasizes backend engineering, system design, observability, CI/CD, incident response, performance, scalability, and mentoring in a fully remote, distributed team.

Design, build, and evolve machine learning systems that power Hopper's pricing engine: implement automated training pipelines, ETL and feature engineering, deploy real-time ML pricing solutions, monitor production for latency/drift/skew, and run champion-challenger tests. Requires ~5+ years experience and proficiency with Python, Scala, SQL, distributed data processing and production ML systems.

Remote Senior Backend Engineer role at DuckDuckGo focused on developing performant, testable backend systems and data pipelines (Perl v5, Go, Node.js). Responsibilities include implementing AI-assisted features for Search and Duck.ai, maintaining search relevancy, mentoring engineers, and collaborating cross-functionally. Compensation listed at $178,500 USD/year plus stock; role expects ~40 hours/week and travel ~2 times/year for company meetups.

Senior-level Design Engineer role focused on both high-quality visual design and technical implementation. You will expand and maintain the design system, design and implement UI/UX at scale, and collaborate with product and engineering (TypeScript/React/GraphQL/Node.js/Postgres/Redis stack). The role is based in the EU (multiple countries listed) and the product reaches large numbers of users.

Ashby seeks a Staff Software Engineer (Product Engineering) to take ownership of large product areas and ship end-to-end features. The role expects full-stack work (frontend and backend), product spec and design involvement, and collaboration across engineering, product, and design. Tech stack examples: TypeScript, React, GraphQL, Node.js, Postgres, Redis. The role is open to candidates in multiple European countries and includes occasional in-person meetups.

Ashby is hiring a Senior Product Engineer (full-stack) for the EU who will take ownership of large product areas and deliver end-to-end projects: research, write product specs, wireframe, prototype and implement. The role emphasizes product thinking, ownership, and collaboration (pair programming), and lists a tech stack including TypeScript, React, GraphQL, Node.js, Postgres and Redis. The position is EU-focused with in-person meetups at least twice a year.

Senior individual contributor role (8+ years) focused on technical leadership for Reddit's Home feed on Android: design and implement Android architecture, drive developer workflow improvements, collaborate with product/design/ML teams, own experimentation and metrics, and mentor engineers. Remote within the United States, Canada, or Europe; hybrid near listed offices is also possible.

Join Docker's Infrastructure Engineering team to develop and operate platform services and APIs (primarily in Go), codify infrastructure with Terraform and GitOps, and scale Kubernetes/EKS and networking foundations. The role includes building AI-assisted operational automation, owning operational readiness and SLOs, and participating in an on-call rotation to support incident response.

Capchase seeks a Senior Tech Generalist with 5+ years building production-scale software to design, develop, and maintain customer-facing and internal systems, own core financial systems (payment orchestration, ledger, underwriting, reconciliation), integrate third-party financial APIs, and improve scalability, reliability, and observability. Proficiency in TypeScript and Node.js is required; Kubernetes, BigQuery, and GCP familiarity are bonuses.

Work on AI Infrastructure to design and operate high-performance, reliable production systems that power AI agents. Responsibilities include building Rust services for model inference and orchestration, designing scalable systems for millions of users, implementing MLOps and model deployment patterns, and defining observability and failure handling. Requires 5+ years building high-scale production systems and strong Rust and distributed systems expertise.

Lead technical direction for LLM inference optimization (Kimchi), improving throughput, lowering latency, and maximizing KV cache efficiency across GPU SKUs and distributed topologies. Requires 5+ years building ML systems/inference or training infrastructure, strong Python, hands-on experience with vLLM/SGLang/TensorRT-LLM, quantization fluency, distributed systems knowledge, and a measurement-first approach. Remote-first role available in multiple European countries.

Wizeline seeks a Senior .NET Software Engineer based in Spain. Must-haves include cloud computing experience, solid understanding of event-driven distributed systems and message brokers, strong SQL skills, daily use of IaC and CI/CD, strong observability and scalable design practices, and the ability to mentor and lead smaller initiatives. Clear and confident English communication is required. Familiarity with AI tooling is listed as a nice-to-have.

Datadog is hiring an Engineering Manager for the OrgStore Blueprint team in Madrid (hybrid). The role leads a 4–8 person software engineering team building and maintaining Postgres-based, OLTP-focused data storage and platform infrastructure. Key responsibilities include driving the technical roadmap, mentoring engineers, contributing to code and design decisions, participating in on-call rotations, and working closely with product and support teams. The position emphasizes reliability, fault tolerance, database operation experience, developer tools, and use of AI coding tools in engineering workflows.

Kodify is hiring a Software Developer in Test (SDET) for a fully-remote EU role (optional Barcelona office). The role requires 4+ years in QA automation/SDET, strong programming experience in JavaScript/TypeScript, hands-on experience with modern automation frameworks (e.g., Playwright, Cypress, TestCafe, WebdriverIO, Jest, Mocha), API testing (REST/GraphQL), and integrating automation into CI/CD (GitHub Actions, Jenkins, GitLab CI). Candidates should be familiar with microservices, cloud/container environments (AWS, Docker, Kubernetes), Cloudflare, Git workflows, and remote Agile collaboration (core hours 10:00–15:00 CET). Responsibilities include designing, developing and maintaining automated UI and API test suites, embedding automation in pipelines, analysing test results, and contributing to QA strategy and tooling.

Research and develop techniques to GPU-accelerate deep learning, machine learning and AI workloads; analyze and optimize complex AI and HPC algorithms on modern CPU/GPU architectures; publish and present findings and collaborate with hardware, software and research teams. Requires an advanced computational degree (or equivalent), 15+ years' relevant experience, fluency in C/C++, parallel programming experience (CUDA, OpenACC, OpenMP, MPI, pthreads), and deep knowledge of CPU/GPU architecture and low-level performance optimization.

Senior Mobile Engineer joining a cross-functional product squad to design, implement and maintain features using Kotlin Multiplatform. Responsibilities include end-to-end feature ownership, collaborating with product and design, maintaining code quality and test coverage, mentoring teammates, and working with a stack that includes Kotlin, Jetpack Compose, SwiftUI, kotlinx.coroutines, kotlinx.serialization, Ktor and SQLDelight.

Hubstaff is hiring a Senior Product Engineer for its Growth team. The role is a remote, ~40 hrs/week independent contractor position focused on building and owning customer-facing features end-to-end using Ruby on Rails, PostgreSQL, and frontend technologies (Vue.js, Hotwire, Tailwind). Responsibilities include designing and running experiments (A/B tests), collaborating with Product, Design and Data, and shipping rapid iterations to improve acquisition, activation, engagement and retention. Hiring is listed for Argentina, Brazil, Canada, Poland, Romania, Spain and Portugal.

Senior, hands-on Staff Product Engineer (Ruby on Rails). Remote role owning hard PRs and end-to-end product areas (billing, enterprise auth, API, dashboard, infra), responsible for performance, security, mentoring via code review, and shipping production Rails code. Fluent English and prior Stripe/billing experience required.

SearchApi seeks a remote Ruby Engineer to build and maintain web-scraping integrations and browser automation (CDP), tackle anti-bot evasion, optimize concurrency, and support production systems at scale. The role involves debugging production issues, reverse engineering protections, contributing across the stack (Ruby on Rails, PostgreSQL, Redis, Sidekiq), customer-facing support, and improving monitoring and infrastructure (Terraform, AWS, Prometheus, Grafana).