Top Software Engineer Jobs in Barcelona

Develop and maintain highly available, secure, scalable API services for a global payments platform. Design and ship new products, improve platform performance, automate development processes, participate in Agile practices, and collaborate with global technology teams. The role requires strong Golang development skills, event-driven architecture experience, relational database knowledge, and familiarity with web and API solutions.

Develop, test, debug, and maintain complex software components; participate in requirements definition, design and code reviews, production troubleshooting, technology evaluation, and solution research. Collaborate with cross-functional teams, provide technical expertise, mentor junior engineers, and take ownership of complex technical challenges.

Build and scale an AI-powered translation and localization platform using Java and Spring Boot. Develop REST APIs, microservices, and Kafka-driven pipelines; integrate LLMs and machine translation providers; optimize quality, scalability, latency, and cost; and support monitoring, testing, deployments, and production troubleshooting. Collaborate with engineering, product, and business stakeholders to expand multilingual content capabilities.

Build and improve reliable, user-focused product experiences across the frontend and backend. Partner with Product, Design, and Engineering to understand user needs, propose solutions, implement features, troubleshoot software, write documentation, and contribute to technical and product decisions. Develop tested JavaScript or TypeScript code using React, Node.js, and related technologies while continuously learning and taking ownership of increasingly complex problems.

Build scalable, maintainable frontend applications using React, JavaScript, and Next.js. Develop reusable component libraries and design systems with Storybook and CSS-in-JS, ensuring WCAG 2.1 AA accessibility. Write clean, tested, documented code; optimize performance and cross-browser behavior; and collaborate with Product, Design, Backend, clients, and stakeholders. Work in Agile environments and use AI tooling to improve development workflows.

Develop and maintain AI-powered web products and platforms using React, Next.js, Node.js, GraphQL, and related technologies. Responsibilities include writing clean, tested, documented code; making architecture and technology-stack decisions; adapting across varied stacks; collaborating with clients and teams; applying web standards, accessibility, and optimization practices; and using AI tools to improve workflows.

Build, launch, monitor, and support scalable backend services in an agile build-and-run environment. Design and improve distributed systems, microservices, APIs, data architectures, and service performance. Contribute to frontend features when needed, support technical decision-making, mitigate production issues, and promote clean code, collaboration, and knowledge sharing. The role requires strong ownership, system design expertise, and a full-stack product mindset.

Build scalable web applications as part of Clio’s full-stack engineering team. Responsibilities include solving complex customer problems, collaborating across distributed Agile teams, learning and applying new technologies, reviewing peer code, mentoring developers, and optimizing databases. The role is based in Barcelona with hybrid office attendance and focuses on reliable, performant SaaS products for legal professionals.

As a Senior Product Software Engineer, you will design, develop, and maintain software applications, collaborate with teams, optimize performance, and provide technical support.

Develop and enhance iOS applications using Swift and SwiftUI while translating business requirements into technical designs. The role involves making technology and infrastructure decisions, documenting architecture, improving team efficiency, mentoring and identifying engineering talent, and collaborating with technical and business stakeholders in English and Spanish. Experience with APIs, third-party libraries, mobile architectures, Git, DevOps, and published iOS apps is required.

Lead Android application architecture and technical decisions; establish development, testing, monitoring, and change-management processes; collaborate with product teams; reduce technical debt; and improve engineering productivity. The role requires native Android development with Kotlin and Jetpack Compose, plus knowledge of system design, APIs, design patterns, declarative UI, Git, and DevOps. Full-stack, cloud, GraphQL, Firebase, and AI tooling experience are advantageous.

Develop and modernize native iOS applications using Swift and SwiftUI. Improve application performance, scalability, reliability, and delivery efficiency while integrating cloud services and advanced technologies. Collaborate with cross-functional teams, document technical decisions, and apply API design, MVVM, declarative UI, data structures, system design, Git, and DevOps practices. Familiarity with GraphQL, Firebase, full-stack development, and AI tooling is advantageous.

Build and maintain software services and platforms for Stripe Tax. Own projects end to end, including scoping, design, implementation, and production deployment. Collaborate with product, design, infrastructure, marketing, and operations teams; debug production issues; improve operational health; pursue short- and long-term goals; and uphold engineering, security, and technical design best practices.

Develop and enhance a live drive-thru Voice AI product through software engineering, AI/LLM prototyping and fine-tuning, conversation analysis, system integrations, and customer requirements gathering. Build, test, deploy, and improve production features while evaluating real dialogs and collaborating with customers and internal stakeholders.

Develop and enhance treasury automation products using Python and related backend technologies. Build and improve time-series cash-flow forecasting models, troubleshoot production issues, ensure service reliability and uptime, and improve engineering standards, code quality, and simplicity. The role also involves working with APIs, web and backend systems, Vue.js, SQL, and cloud-native infrastructure.

Maintain and evolve FAdmin, a mission-critical Ruby on Rails flyer processing system, and related Content Platform tools. Deliver roadmap features end to end, support service desk requests, use AI coding agents to improve delivery and code quality, write automated tests, participate in code reviews, and maintain CI/CD pipelines. The role requires production software development experience, relational database and SQL expertise, and strong English communication.

Build and operate full-stack systems for an AI-powered offensive security platform. Responsibilities include developing React frontends, TypeScript APIs, Kotlin and Go backend services, deploying on AWS, designing scalable systems, optimizing databases, supporting production, and owning features from concept through deployment. The role involves close collaboration with AI and security researchers in a fast-paced remote startup.

Build and operate high-scale JVM-based backend microservices using Java and Kotlin. Own services across architecture, implementation, deployment, monitoring, on-call support, and continuous improvement. Develop event-driven Kafka systems, apply concurrency and performance optimization, design resilient APIs, and operate containerized services with Kubernetes and CI/CD. Improve observability, reliability, automation, and developer productivity while collaborating cross-functionally, mentoring peers, and contributing to technical standards.

Build BLP’s core software across infrastructure, backend, machine learning, and product extension platforms. Responsibilities include operating secure and observable cloud infrastructure, developing performant distributed systems, applying AI to business problems, and enabling customer process automation. The role emphasizes formal reasoning, correctness by construction, maintainable systems, type systems, and functional programming. Work is available onsite in Zurich or remotely within Europe.

Develop and deploy AI-powered 3D graphics solutions for desktop, web, VR, and AR applications using the Evergine engine. Build computer vision and spatial computing models, including NeRF, Gaussian Splatting, point-cloud processing, SAMv2, and GroundingDINO or FlorenceV2. Design scalable algorithms, integrate machine learning frameworks, and collaborate with research and engineering teams in an Agile environment.

Build AI-powered observability capabilities across Kibana interfaces, agentic investigation systems, telemetry detection pipelines, and evaluation infrastructure. Develop user-facing investigation workflows, agent tools, context and signal-generation systems, and offline and online evaluations. Collaborate with UX designers, product managers, and data scientists to improve autonomous root-cause analysis and remediation for SREs.

Develop and maintain Elasticsearch’s Inference API and plugin framework, integrating internal and external machine learning providers. Responsibilities include API and protocol design, streaming, asynchronous execution, rate limiting, billing integration, provider configuration, testing, open-source contribution reviews, and incident on-call support. The role requires advanced Java expertise, concurrency knowledge, API design skills, and collaboration across distributed engineering teams.

Design, build, and deploy production-grade agentic AI systems: multi-agent orchestration, RAG pipelines, provider integration, LLMOps, observability, and reusable patterns. Embed with client teams, lead design sessions, tune embeddings/vector search, manage cost/latency tradeoffs, and define metrics for accuracy, safety, latency, and cost.

Build backend services, internal developer platforms, tooling, CI/CD systems, testing capabilities, and paved paths using Python. Improve developer experience, productivity, and the software delivery lifecycle through cloud-native, distributed systems and AI-driven workflows. Collaborate with engineering teams as platform users, use data and feedback to measure effectiveness, and influence architecture and technical decisions.

Architect, develop, and scale cloud services, dashboards, and data pipelines to support robotics and autonomous vehicle telemetry. Integrate IoT devices with Azure services, build APIs/microservices, implement observability and CI/CD, validate systems in lab and field, and mentor junior engineers.