Top Software Engineer Jobs in Barcelona

Six-month full-time graduate program for final-year or recent engineering graduates. Work in production from day one, contribute to global-scale systems, learn from experienced engineers, and develop foundations in backend development, testing, CI/CD, cloud, and best practices. Potential transition to a permanent role after the program.

Software Engineers at QuantCo will design and develop scalable solutions, integrate models into client businesses, and improve products based on client feedback.

As an Ubuntu Core Software Engineer, you will design and implement features for the embedded Linux operating system, maintain boot mechanisms, debug system-level issues, and collaborate with a global team.

The System Software Engineer prepares customer analysis for traffic control software, develops customer-specific solutions, and supports project management and engineering teams throughout the project lifecycle.

Define and document system requirements, develop and validate embedded software and control algorithms for air-to-water heat pumps, debug microcontroller code, verify prototypes and software behavior, and support communication protocol development (CAN, Modbus, UART) while collaborating with electronics and controls teams to meet product performance and safety targets.

Develop, test, and maintain secure, scalable Salesforce enterprise software across the full delivery lifecycle. Responsibilities include architecture, hands-on coding with Apex, Visualforce, and Lightning Components, asynchronous processing, automated testing, documentation, Agile collaboration, code reviews, clean-code practices, and deployment. The role also involves contributing to engineering standards, continuous process improvement, knowledge-sharing communities, and mentoring other developers.

As a Senior Tech Generalist, you'll build and maintain end-to-end systems, improve scalability, and ensure reliable financial operations while mentoring others in a dynamic team environment.

Design and implement backend trading services, own features end-to-end (schema, API, tests, UI integration), contribute to real-time infrastructure and client-facing APIs, and write integration tests against real dependencies.

Full-stack Developers at QuantCo build user interfaces for machine learning solutions, collaborating with data scientists and engineers to deliver actionable products.

Staff Software Engineer responsible for leading architectural evolution across a distributed rendering platform, contributing to core backend systems, and improving performance, reliability, scalability, testing, and delivery practices. The role includes mentoring engineers through pairing and design reviews, unblocking teams, shaping technical strategy, improving CI/CD and tooling, and aligning engineering investments with product and business goals.

Build and maintain integrations for North's agentic platform, own the end-to-end integration pipeline, create evals and tests to ensure reliability, tune tool descriptions, and help other engineers add and maintain integrations while using AI responsibly to improve performance and quality.

As a Staff Software Engineer, you will define engineering vision, lead large projects, ensure code quality, and mentor engineers while enhancing the scalability of the platform.

The Senior Software Engineer will lead development initiatives, manage technology processes, and ensure effective collaboration with business partners while focusing on improving database operations and client engagement.

The Lead Software Engineer will develop AI-powered software, focusing on backend systems, APIs, microservices, and collaborating in agile teams to deliver technical solutions.

The Lead Software Engineer will develop AI-powered software solutions, design backend systems, and collaborate with cross-functional teams to enhance AI capabilities.

Lead and deliver quarterly goals for a backend team building low-latency payment and ledger systems. Design, implement, and operate scalable backend services, collaborate with product/design/analytics, own on-call and availability, set code/design standards, and mentor engineers.

Lead backend engineering for EU cards: set technical strategy, design low-latency transaction and ledgering systems, ensure operational reliability (monitoring, on-call, playbooks), collaborate cross-functionally, mentor engineers, and drive code and design quality across teams.

Design, build, and maintain performant React/Redux/Vite web applications and data-visualization portals. Collaborate across teams to implement features and RESTful APIs, write tests, perform code reviews, debug complex issues, follow agile and CI/CD practices, refine UX details, and adopt tooling to speed development.

Design, build, ship, and own high-scale, user-facing product features across frontend, backend, and data systems. Define problems, scope and prioritize work, collaborate with Product, monitor production usage, debug incidents, improve reliability, review code, and mentor engineers. The role requires strong backend expertise alongside React proficiency and ownership from product discovery through long-term maintenance.

Build and ship production AI agents that help mobile app developers manage subscriptions and paywalls. Own agent orchestration, tool execution, context management, evaluation, observability, permissions, and human-in-the-loop controls. Develop reliable, secure, user-facing backend systems, scope projects independently, monitor adoption, improve features after launch, participate in architecture and incident response, and mentor engineers.

As a Growth Software Engineer, you will scale user and business growth through experimentation, data-driven development, and cross-functional collaboration, particularly in user engagement and retention.

The AI Software Engineer will develop and improve Joko's AI shopping assistant, focusing on architecture, evaluation, data management, and personalized user experiences, while collaborating with product teams.

The Software Engineer will develop backend systems using Rust, manage multimodal data, and improve data infrastructure with a focus on performance and design ownership.

Own and resolve production customer issues end-to-end: debug integrations, browser JS, agents and prompts, and database issues. Communicate directly with customers, build automation and runbooks to prevent recurrence, surface recurring patterns to Product, and raise team capability through tools and documentation.

Canonical seeks open-source enthusiasts to optimize Ubuntu for new silicon technologies, collaborating with teams and customers to enhance software quality and performance across various platforms.