Senior+ Full-Stack Engineer
Quick Summary
This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Senior+ Full-Stack Engineer based in Spain.
As a Senior+ Full-Stack Engineer, you will build and evolve a developer infrastructure platform that enables AI applications and agents to connect seamlessly with external APIs and services. You will take ownership of product features from initial customer discovery and technical design through implementation, deployment, and continuous improvement. Working across backend services, APIs, runtime systems, and frontend interfaces, you will help deliver reliable, scalable, and intuitive tools for developers. You will collaborate directly with customers to understand their needs and translate real-world challenges into impactful product solutions. In this highly autonomous role, you will influence technical architecture, product strategy, and the engineering roadmap. You will join a remote-first, startup environment that values ownership, pragmatic problem-solving, open-source collaboration, and a strong developer experience.
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Design, develop, and ship full-stack product features, working across backend services, APIs, runtime infrastructure, dashboards, and developer-facing interfaces.
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Build and maintain the tools developers and AI agents use to interact with the platform, including APIs, SDKs, command-line interfaces (CLI), Model Context Protocol (MCP) integrations, and web applications.
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Engage directly with customers to understand their integration requirements, workflows, and AI agent use cases, translating feedback into product specifications and practical technical solutions.
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Own entire product features and technical initiatives from discovery and architecture through development, testing, deployment, and ongoing optimization.
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Design and maintain scalable, high-performance systems that remain reliable as customer adoption, integration complexity, and usage volumes increase.
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Contribute to product strategy and roadmap prioritization, making informed technical and product decisions that balance customer needs, engineering quality, and business objectives.
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Improve developer experience across all product surfaces by creating intuitive interfaces, clear APIs, reliable integrations, and accessible documentation.
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Contribute to the development and maintenance of open-source projects, engaging with the developer community and supporting the evolution of shared tools and repositories.
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Collaborate closely with engineering teammates and other stakeholders in a remote-first environment, sharing knowledge, resolving blockers, and supporting incident response when necessary.
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Identify opportunities to improve engineering practices, system architecture, and product functionality while maintaining a strong focus on shipping useful features and delivering measurable customer value.
Requirements
~2 min read-
At least 5 years of software engineering experience at a senior level or above, with strong foundations in backend development, API design, database architecture, distributed systems, and performance optimization.
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Strong TypeScript skills and the ability to work confidently across the stack, including Node.js backend services and React-based frontend applications.
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Demonstrated experience building and shipping production-ready software, with the ability to take ownership of complex features from initial concept to successful release.
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A product-oriented mindset, with a genuine interest in understanding customer problems, evaluating trade-offs, and building solutions that deliver meaningful value rather than focusing solely on technical implementation.
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Strong communication and collaboration skills, including the ability to work directly with customers, explain technical concepts clearly, and coordinate effectively with teammates in a remote-first environment.
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A strong commitment to developer experience, with an understanding of the importance of intuitive APIs, well-designed developer tools, reliable integrations, and polished user interfaces.
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Excellent problem-solving skills, sound technical judgment, and a pragmatic approach to engineering decisions, including the ability to respond constructively to incidents and help unblock others.
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A high degree of autonomy, accountability, and adaptability, with the ability to navigate ambiguity, prioritize effectively, and make progress in a fast-moving startup environment.
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A collaborative, low-ego attitude, with a willingness to take initiative, share knowledge, receive feedback, and contribute to the team's overall success.
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Based in the Netherlands or otherwise eligible to work remotely from the designated European region.
Nice to Have
~1 min read-
Experience building AI agents or agent infrastructure for production environments, including tool calling, orchestration, evaluation frameworks, or MCP integrations.
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Previous experience working directly with customers in forward-deployed engineering, solutions engineering, or other developer-facing technical roles.
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A track record of delivering polished frontend experiences, particularly dashboards, developer portals, or other technical user interfaces.
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Experience building developer tools, contributing to open-source software, or maintaining community-driven repositories.
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Familiarity with API integration platforms, developer infrastructure, or products that connect AI applications with external services.
What We Offer
~2 min readLocation & Eligibility
About this job
- Who can apply
- Spain
- Posted
- Today
Listing Details
- Posted
- October 22, 2026
- First seen
- October 22, 2026
- Last seen
- October 22, 2026
Posting Health
- Days active
- 0
- Repost count
- 0
- Trust Level
- 68%
- Scored at
- October 22, 2026
Signal breakdown
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