Top Software Engineer Jobs in Barcelona

Senior Software Engineer to design and implement C++/Python software, accelerate workloads with CUDA, develop and maintain Linux kernel modules and system services, optimize system and GPU performance, manage Linux systems, mentor junior engineers, and integrate AI technologies across products.

Staff Software Engineer responsible for designing, building, and operating distributed market data systems. The role focuses on real-time blockchain data ingestion, streaming, normalization, storage, APIs, reliability, data correctness, observability, incident recovery, and production support. The engineer will lead technical decisions, mentor teammates, translate ambiguous requirements into designs, and use AI-assisted development throughout the software lifecycle.

Design, implement, test, deploy, maintain, and improve backend software components for medical software used by surgeons worldwide. Collaborate with product managers, analysts, architects, and engineers to develop high-quality features, apply testing methodologies such as unit testing and TDD, improve team productivity through internal tools, and contribute to technical discussions and product quality.

Own end-to-end B2B merchant product initiatives, from understanding problems and defining hypotheses through building, shipping, measuring, and iterating. Work across backend and frontend production software, collaborate directly with merchants and stakeholders, make product and technical decisions amid ambiguity, and use data, experimentation, and AI-assisted development to deliver outcomes.

Own end-to-end migration of business domains from a legacy desktop ERP to a modern web ERP. Design data models, APIs, tenant isolation, cutover and rollback plans; execute safe live-data migrations; maintain production reliability; review backend and frontend code; collaborate with Product; mentor engineers; and occasionally modify legacy C++ code.

Owns end-to-end test strategy, designs scalable backend and UI automation frameworks, integrates automated testing into CI/CD pipelines, performs exploratory testing, and advocates for testability and reliability across engineering and product. The role requires strong programming, Kubernetes and distributed-systems knowledge, debugging ability, and cross-functional ownership in a fast-moving startup.

Develop and guide the architecture of native iOS applications using Swift and SwiftUI. Lead technical discussions, establish software development and testing processes, address technical debt, evaluate frameworks and scalable approaches, and collaborate with product teams on business-aligned solutions. The role also includes mentoring engineers, applying design patterns and API design, using Git and DevOps practices, and exploring AI tooling, cloud services, GraphQL, and Firebase.

Develop cross-platform C++ mapping SDK components for native applications, visualization, sensor networks, navigation, and Unity and Unreal Engine integrations. Responsibilities include designing software with modern C++ standards and patterns, extending core components through plugin APIs and UI, writing unit tests, collaborating in an agile team, and continuously improving technical skills.

Own and develop low-level systems powering cloud-based scientific workloads across Fusion, Fusion Snapshots, Ignite, and Sched. Build reliable systems software in Go and C, work with Linux internals, filesystems, namespaces, process supervision, checkpoint/restore, and multi-cloud orchestration. Lead performance engineering, testing, observability, and operational excellence while mentoring engineers and shaping technical direction.

Own the backend application layer for compute provisioning, cloud and HPC integrations, usage metering, billing, and customer onboarding. Design APIs and data models, integrate AWS, Azure, GCP, Kubernetes, and GPU environments, improve observability and failure handling, and support production customers. Collaborate with product, platform, infrastructure, and support teams while making architecture decisions and documenting systems.

Lead test framework architecture and continuous execution pipelines for cloud platform features. Define automation standards, shape quality engineering strategy, mentor engineers, and improve release stability. Build automated testing frameworks using Python, Pytest, Go, or Bash, with emphasis on highly available Kubernetes services, containers, cloud-native technologies, Linux systems, networking, security, and CI/CD practices.

Design and develop the core vCluster Platform, focusing on Kubernetes internals, tenant isolation, container orchestration, and scalable resource-sharing systems. Build high-performance Go software, own features from technical design through release, solve complex systems-architecture problems, and contribute to open-source projects. The role requires autonomous technical leadership, active collaboration with the Kubernetes community, and experience in high-growth startup environments.

Leads test strategy, framework architecture, and platform quality initiatives for Akamai’s cloud-native Compute platform. Partners with leaders and architects on testing roadmaps, mentors engineers, establishes automated continuous deployment testing standards, and advances scalable testing methodologies. Requires expertise in test automation, software platform engineering, CI pipelines, infrastructure, networking, Kubernetes, cloud-native services, Python, Go, Linux, and security principles.

Design and build the vCluster Platform using Kubernetes internals and Go. Own features end to end from technical design through release, solve complex systems architecture problems, contribute to open-source projects, and develop scalable tenant isolation and resource-sharing solutions. The role requires autonomous technical problem solving, strong Kubernetes expertise, and participation in a high-growth startup environment.

Architect and develop production-grade business systems across Salesforce, NetSuite, and integrated enterprise platforms. Build quoting, subscription, and entitlement engines; create automation pipelines and API integrations; establish architecture, security, documentation, and code-review standards; and translate commercial policies into scalable technical solutions. The role partners with Finance, Sales Operations, Customer Success, and product stakeholders while maintaining system reliability, auditability, observability, and production readiness.

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 and own scalable AI-powered features for Dow Jones GenAI products, spanning backend APIs, data layers, user-facing integrations, and production operations. Integrate LLM and AI APIs, develop prompt management and evaluation tooling, improve observability and CI/CD, and apply MLOps practices for model versioning, monitoring, and experiment tracking. Partner with product managers, data scientists, and engineering leads while mentoring colleagues and driving technical direction.

Lead software engineering for Dow Jones Energy applications, including complex coding, deployment, bug resolution, legacy maintenance, cloud solutions, and CI/CD automation. Mentor engineers, conduct code reviews, develop technical strategies, and improve reliability across AWS and Azure environments. The role also introduces responsible AI-augmented development practices and provides operational support, including off-hours and weekend coverage.

Develop and maintain production-grade computer vision software for AI-enabled parcel management and automated logistics systems. Responsibilities include processing camera data for real-time decisions, integrating AI models and frameworks, designing scalable architectures, optimizing and deploying solutions, and contributing to technology roadmaps. The role also involves collaboration with product and engineering teams, technical leadership, mentoring junior engineers, and establishing software engineering best practices.

Design, implement, test, and ship Firefox security and hardening features for enterprise users. Improve security architecture across operating systems, including privilege isolation, trust boundaries, cryptographic protocols, WebPKI, and security-sensitive web APIs. Investigate security issues, resolve root causes, and improve browser reliability, performance, memory usage, and correctness in a complex multithreaded codebase.

Own the frontend architecture and production delivery of a multi-brand consumer platform built with React, Next.js, and TypeScript. Responsibilities include creating a configurable multi-brand system, owning a design system and component library, converting AI-built prototypes into production features, using AI coding agents, and ensuring high UI quality, performance, accessibility, and Core Web Vitals. The role requires autonomous end-to-end ownership and daily production coding.

Design and build the on-prem software stack for ModelVault appliances: containerized inference engines, model integration (LLMs/vision), deployment tooling, CLIs/GUI/APIs, OS and GPU setup, remote updates, telemetry, and collaborate with customers and founding team to iterate and scale the engineering org.

Build core components of a diagnostic and personalization platform: backend data pipelines, frontends, services for genomic data ingestion, ML model integration, APIs, and cloud infrastructure. Collaborate with product and ML teams, iterate on prototypes and MVPs, and make architectural decisions supporting scalability and reliability.

Build and maintain Ergodic AI’s AI platform across back-end and front-end systems. The role involves developing with Python web frameworks and JavaScript/TypeScript, integrating with client technology stacks and workflows, applying AI, ML, and LLM concepts, and contributing to DevOps, cloud deployment, testing, and infrastructure practices. As an early-stage hire, the engineer will help shape the product and solve complex data and AI challenges.

Design and implement large-scale browser-based rendering infrastructure to execute and extract structured content from JS-heavy web apps. Improve rendering quality, performance, cost, and throughput at internet scale and productionize rendering research.