Top Software Engineer Jobs in Barcelona

Build and scale Java backend services, Kafka streaming pipelines, microservices, and APIs for personalization using behavioral data. Deploy and operate software on AWS, participate in architecture and on-call responsibilities, automate operational processes, and evaluate AI coding tools. The role requires distributed systems, concurrency, asynchronous programming, and production cloud experience, with bonus experience in GraphQL, Kubernetes, data processing, recommendation systems, agentic AI, and data modeling.

Build and operate full-stack repayment user experiences for millions of consumers. Break projects into deliverable phases, collaborate with product, design, and analytics, monitor system metrics, participate in on-call support, review code, and develop well-tested backend and web applications. The role requires backend development with Python or Kotlin and web application experience with React or Vue.

Supports Unity game development for mobile games by building gameplay features, internal tools, and workflows; testing, debugging, and optimizing experiences; participating in code reviews; collaborating with designers, artists, and developers; proposing technical solutions; and documenting improvements. The role is intended for a student pursuing computer science, game development, or a related field with Unity and C# experience.

Develop and launch scalable backend systems for Affirm Card checkout products. Collaborate with product, design, analytics, and engineering teams to deliver phased projects, ensure system availability, monitor metrics, participate in on-call support, review code, debug systems, and contribute to interviews and team development.

Develop and maintain Odoo 20 customizations for finance, project-management, and expense systems. Build integrations with Microsoft Dynamics, Zoho, and banking platforms; perform scripted historical data migrations; maintain testing pipelines and test data; collaborate on requirements, estimates, and risks; update technical documentation; and support the system after go-live.

Own the architecture and delivery of backend services for New Relic’s behavioral data platform. Build and operate Java-based distributed systems and Kafka streaming pipelines in AWS, ensure reliability and scalability, guide technical design, mentor engineers, collaborate with product stakeholders, and help adopt AI coding tools. The role also contributes to GraphQL, Kubernetes, data processing, personalization, recommendation systems, and agentic AI experiences.

Lead a cross-functional squad of software engineers and data scientists responsible for a production budgeting platform. Own end-to-end budget allocation, payback-based modeling, technical strategy, reliability, data quality, and product delivery. Develop people, hire talent, make architecture and prioritization trade-offs, and partner with marketing, finance, analytics, and product stakeholders. Translate uncertain modeling outputs into clear business recommendations while building scalable, tested, monitored, and reproducible decision products.

Provides first-level support for production-line end-of-line test stations, diagnosing incidents, monitoring test results, documenting resolutions, maintaining test software, and supporting operational systems. Assists with reports, dashboards, data traceability, scripting, automation, process documentation, continuous improvement, and equipment certification tracking while collaborating with production, quality, engineering, and systems teams.

Build, test, deploy, and maintain scalable web and mobile applications. Own features from concept through launch while collaborating with Product, Design, Data Science, and engineering teams. Apply automated testing, strong code quality practices, relational database and schema design expertise, analytical problem-solving, and user-focused design. Work within agile methodologies and contribute to continuous deployment, production monitoring, knowledge sharing, and ongoing engineering improvement.

Develop and maintain cybersecurity attack test benches for side-channel analysis, fault injection, protocol validation, and secure product evaluation. Responsibilities include gathering requirements, developing Java and C features, integrating lab instruments, creating secure test applications, validating releases, maintaining CI/CD pipelines, and documenting architecture and technical specifications.

Lead the technical direction and evolution of Affirm’s Recoveries platform. Design and operate scalable, correctness-sensitive backend systems supporting loan recoveries, partner integrations, payments, reconciliation, bankruptcy workflows, and customer experiences. Drive cross-team initiatives, improve reliability and observability, establish engineering standards, participate in on-call operations, and mentor engineers while ensuring regulatory compliance and strong data integrity.

Own and deliver repayment user experiences across mobile, web, and backend systems. Lead engineers through ambiguous problems, collaborate with product, design, and analytics, and drive technical decisions. Monitor reliability and availability, participate in on-call rotations, improve engineering standards, mentor teammates, and deliver scalable, high-quality software for consumer finance users.

The Robotics Test Automation Engineer will develop and maintain automated test pipelines, ensure reliable regression tests, and support CI/CD integration to enhance testing while collaborating with developers.

Build and maintain Ruby on Rails APIs for internal workflows, from stakeholder discovery and requirements refinement through design, testing, release, and evaluation. Write secure, maintainable code handling authentication, authorization, and sensitive data. Troubleshoot API issues, add regression coverage, participate in design discussions, review code, document decisions, and collaborate asynchronously in a distributed agile team.

Develop production Rust code for managing, reconfiguring, and adapting cloud resources within a Kubernetes development platform. Collaborate on architecture, infrastructure, and feature design; use AI to improve delivery; and work directly with users to gather requirements and debug complex distributed environments. The role requires strong systems thinking, cloud-native infrastructure knowledge, and effective async collaboration in a remote-first startup.

Develop and maintain scalable full-stack software for user, license management, and provisioning capabilities. Translate business requirements into reliable solutions, own development increments, test and debug applications, address security and technical issues, and contribute to code reviews, architecture, performance, and engineering practices. The role requires AWS experience, proficiency in C#, TypeScript, Angular, or React, and knowledge of software design, databases, authentication, and authorization.

Leads architecture, development, optimization, testing, and delivery of modern C++ 3D software for clinical dental applications. Owns rendering, geometry, APIs, CI/CD, and cross-language integrations while applying AI-assisted development practices. Investigates complex defects, mentors engineers, leads technical discussions, collaborates across product and manufacturing teams, and ensures compliance with medical device software quality processes.

Build and scale Nuitee’s flight infrastructure from a production product into reliable API-first platform services. Responsibilities include API design, caching volatile flight offers, modeling booking data, supporting booking changes, cancellations and refunds, integrating NDC and legacy GDS flows, and improving performance and reliability. This hands-on individual contributor role requires deep backend and API expertise, flight-domain knowledge, Python experience, and ownership in a small team.

Develop and maintain native Android applications using Kotlin and Jetpack Compose. Apply system design, data structures, design patterns, API design, declarative UI, MVP or MVVM, Git, and DevOps practices. Collaborate on innovative AI-powered digital products, explore new technologies, and potentially contribute across the full stack using cloud services, GraphQL, and Firebase. This hybrid Barcelona role requires three office days per week.

Build and maintain ERP business management features across backend services, APIs, databases, and user interfaces. Develop reliable software, implement database models and schema changes, investigate issues, write tests, monitor releases, conduct code reviews, and communicate risks. The role requires professional software development experience and offers opportunities to grow into larger engineering responsibilities while working with technologies including Python, Django, React, PostgreSQL, AWS, and Kubernetes.

Build and ship healthcare software across the frontend, API, and database using React, TypeScript, Next.js, tRPC, Prisma, and related technologies. Own features end to end, prototype with AI tools, test with patients and care teams, and improve performance, accessibility, reliability, and scalability. Collaborate closely with company leadership in a fast-paced startup environment while developing trustworthy automation for healthcare delivery.

Build and ship healthcare software across the frontend, APIs, and databases. Own features end to end, write tested and maintainable code, prototype with patients and care teams, and use AI tools such as Cursor and Claude Code in daily development. Design scalable systems, improve performance, accessibility, and reliability, and contribute to trustworthy automation in a fast-paced startup environment.

Designs and builds Notabene’s Go-based transaction platform for secure, scalable, multi-tenant crypto transfers. The role focuses on distributed systems correctness, PostgreSQL performance, cloud infrastructure, observability, auditability, and regulated-data security. The engineer owns production operations, writes technical designs, reviews code, mentors teammates, collaborates with product and compliance teams, uses AI coding agents, and participates in on-call rotations.

Build and own agentic platform capabilities end to end, from architecture and implementation through production. Develop reliable, secure, cost-efficient systems for AI runtimes, evaluations, sandboxes, tool gateways, permissions, and agent workflows. Collaborate with Alaners, product teams, and operations; improve developer and user experience; mentor engineers; and contribute to product and engineering culture.

The Software Developer will build scalable web applications, collaborate with full-stack engineering teams in an Agile environment, solve complex customer problems, review peer code, and contribute to cross-team projects. The role requires software development experience, database optimization knowledge, strong communication, adaptability to new technologies, and mentorship experience. It is based in Barcelona with hybrid office attendance expected at least twice weekly.