Founding Senior Software Engineer

This position is listed on behalf of a partner company, which manages all applications and next steps. Our partner is looking for a Founding Senior Software Engineer based in Spain.

Join a fast-growing technology startup building an AI-powered platform that transforms how organizations discover, understand, and act on information from across the digital world. As a key member of a lean engineering team, you will have the opportunity to shape the technical architecture, influence core product decisions, and drive development from concept to production. You will build scalable software systems and integrate advanced AI capabilities into real-world workflows. Your work will reach hundreds of customers quickly, giving you direct visibility into product impact and user feedback. This role offers significant ownership, technical autonomy, and the opportunity to help establish engineering foundations for long-term growth. If you enjoy solving complex challenges, moving quickly, and building impactful products in an ambitious startup environment, this opportunity is for you.

Accountabilities

• Architect, design, and develop core software systems, making key technical decisions across the technology stack while balancing immediate product needs with long-term scalability.
• Own feature development end-to-end, from technical design and implementation to deployment, monitoring, and continuous improvement.
• Integrate AI and machine learning capabilities into production workflows, including large language models (LLMs), retrieval-augmented generation (RAG) pipelines, embeddings, prompt execution, agentic systems, and fine-tuned models.
• Build scalable, reliable, and maintainable systems capable of supporting significant business growth while making pragmatic infrastructure and architecture decisions.
• Develop high-performance APIs, backend services, and internal interfaces that power the product, ensuring reliability, security, and a seamless customer experience.
• Design and improve data processing systems, distributed architectures, and real-time pipelines to efficiently ingest, process, and analyze large volumes of information across text, audio, and video.
• Collaborate closely with the engineering team and other stakeholders to translate product requirements into effective technical solutions.
• Deliver features rapidly, gather user feedback, and iterate continuously to improve product functionality and performance.
• Contribute to engineering best practices, technical standards, and infrastructure decisions that support the team's continued growth.

Requirements:

• At least 3 years of experience building, deploying, and scaling production-grade software systems, with strong foundations in backend engineering, services, data modeling, and distributed systems.
• Deep expertise in at least one technical area, combined with a willingness to expand your knowledge across the broader engineering stack.
• Proficiency in one or more relevant backend technologies, such as Python, TypeScript, and PostgreSQL, with an understanding of high-concurrency systems.
• Experience with cloud infrastructure, preferably AWS or GCP, as well as containerization technologies such as Docker and Kubernetes and modern CI/CD pipelines.
• A strong understanding of software architecture, system reliability, performance optimization, and designing solutions that can scale with business needs.
• Expertise in one or more of the following areas:
  • Data Engineering: Experience with Spark, Kafka, Flink, BigQuery, large-scale ETL processes, or streaming data pipelines.
  • Distributed Systems: Knowledge of high-volume systems, fault tolerance, scalability, and eventual consistency.
  • AI and Machine Learning: Hands-on experience deploying LLMs, RAG pipelines, embeddings, fine-tuned models, or optimized inference systems in production.
  • Backend Engineering: Experience developing robust APIs, backend services, and high-performance applications.
• A strong product-oriented mindset, with enthusiasm for building quickly, shipping features frequently, and incorporating user feedback into continuous improvement.
• Excellent communication skills and the ability to collaborate effectively with engineers and cross-functional stakeholders.
• A proactive, autonomous approach to problem-solving, with the confidence to take ownership of technical decisions and contribute to the direction of a growing engineering organization.

Benefits:

• Meaningful ownership: Play a foundational role in shaping the product, engineering architecture, and technical direction of a growing startup.
• High-impact work: Deliver new features and capabilities directly to a growing customer base, with a clear connection between your work and business outcomes.
• Technical autonomy: Influence decisions across the technology stack and choose practical solutions that balance innovation, performance, and scalability.
• AI-driven innovation: Work hands-on with modern AI technologies, including LLMs, RAG, embeddings, and agentic systems, to solve real-world problems.
• Strong engineering environment: Collaborate with an experienced, ambitious engineering team with backgrounds at leading technology companies.
• Fast development cycles: Build, ship, and iterate rapidly, with opportunities to see your work reach customers without unnecessary bureaucracy.
• Startup growth opportunity: Help establish the technical foundations of an expanding business and grow alongside the product and engineering organization.
• Remote work: The role is advertised for Romania, offering the opportunity to contribute in a remote-first working environment.