Top Software Engineer Jobs in Spain

Build and modernize Mozilla’s Add-ons platform, including automated moderation pipelines, reviewer tools, DevHub, and internal developer platforms. Improve CI/CD, infrastructure as code, observability, reliability, testing, incident response, and production operations. Collaborate with engineers, product managers, designers, QA, reviewers, and contributors while documenting architecture, mentoring peers, and delivering iterative improvements across Python/Django, MySQL, React/TypeScript, and asynchronous systems.

Lead the Search team’s technical direction while designing, scaling, and operating search APIs, semantic retrieval systems, ranking pipelines, and vector search infrastructure. Partner with product and brand stakeholders, mentor engineers, manage Terraform and Chef infrastructure, maintain Jenkins CI/CD, deploy Docker and Kubernetes services, and own reliability, observability, SLOs, and incident response. Champion AI-assisted development practices across the team.

Build and own the architecture for Dune’s curated data lifecycle, including dependency-aware orchestration, backfills, schema evolution, retries, recovery, data quality, and alerting. The role combines backend software engineering with large-scale data systems work across Go, Kotlin, Rust, Python, and SQL. Responsibilities include designing ingestion and curation contracts, making architecture decisions, solving ambiguous problems, and leading work that other engineers can execute.

Leads verification for embedded software supporting datacenter and energy products. Develops test strategies, architectures, automation frameworks, and test code using Python and PyTest; executes tests, analyzes defects, validates releases, and reports quality results. Collaborates with architects, board and systems teams, and distributed stakeholders to improve testability and release reliability. Mentors test engineers and promotes best practices across firmware, APIs, tools, and services.

Design and implement the core components of the Agents Python framework, focusing on API and abstraction development for AI-driven applications.

Design and develop functionalities for the Agents framework, iterate on feedback, and create documentation while working with various programming languages.

Defines certification agreements, audits suppliers, oversees compliance with RTCA/DO-254 and RTCA/DO-178, conducts pre-certification reviews, controls hardware and software documentation, verifies safety and criticality compliance, and coordinates certification activities across engineering, quality, safety, and design teams for aircraft equipment.

Develop and maintain Java backend applications using TDD and clean code principles, participate in full SDLC within Agile/Scrum teams, design technical solutions, deliver sprint increments, support component consumers, and improve team practices.

As an AI Software Engineer, you will lead AI software projects, mentor colleagues, collaborate with stakeholders, and drive best practices in software engineering.

The Software Engineer will maintain and evolve an internal technical product focusing on reliability, standardization, and automation within a backend-heavy role, ensuring effective CI/CD and technical proposals.

The Software Engineer will design, develop, and support technical solutions, working collaboratively with teams to integrate technologies for environmental projects about climate change and biodiversity.

Design and build resilient, high-throughput backend payment services. Evolve distributed, event-driven architectures ensuring idempotency, data consistency, and fault tolerance. Own testing (unit/integration/acceptance), performance simulations, observability in production, mentor engineers, and leverage AI tools to accelerate delivery. Collaborate with Product, QA, DevOps, and frontend teams.

Design and develop core backend components for a blockchain network using Rust, ensuring reliability and scalability in production-grade software.

The Senior Back-End Software Engineer will design and implement a serverless platform, work closely with the product team, and own entire projects, driving innovation in telehealth.

As a Senior Front-End Software Engineer, you'll design and implement services, contributing to the architecture and product strategy in a fast-paced environment.

As a Back-End Software Engineer, you'll design, implement, and scale a serverless telehealth platform using various technologies while working closely with the product team.

Design, build and ship Android features using Kotlin and Jetpack (Compose). Integrate backend REST APIs, improve performance, stability and memory, and craft clean user journeys for financial services. Use analytics and production debugging to iterate and deliver AI-assisted mobile experiences where beneficial.

The role involves designing, building, and implementing new services, working closely with the product team, and taking ownership of projects from 0 to 1.

As a Fullstack Software Engineer, you'll design and maintain internal services and APIs, enabling product teams to innovate efficiently and effectively while enhancing user experience across multiple regions.

The Junior Software Developer will collaborate on a cloud-native monitoring stack, developing features, debugging, and representing Canonical at events.

The role involves creating and automating infrastructure features for data platforms using Python, with a focus on distributed systems and collaboration within a global team.

Join Canonical's OpenStack Engineering team to develop and manage Charmed OpenStack and Ceph, focusing on Python code and infrastructure automation.

The role involves automating OpenSearch operations by developing features in Python, collaborating with an international team, and providing expertise on data platforms.

The role involves collaborating with a distributed team to develop and debug software for Linux, focusing on high-quality code and system-level issues.

As a Software Engineer, you will enhance Ubuntu's cloud infrastructure, automate image delivery, and collaborate with cloud giants, delivering high-quality software features.