About Longtail
Longtail is building an intelligent decision-streaming platform that helps airlines make smarter, faster commercial decisions in real time. Combining automation, proprietary algorithms, AI, and live data, our technology helps airlines optimize pricing, availability, and product flexibility across thousands of routes worldwide.
We're a fast-growing, international team solving complex, real-world problems at scale.
The Role
You'll help build and evolve Sightline, Longtail's conversational analytics and intelligent alerting product, as it moves from beta to a scalable, production-ready platform.
This is a backend-focused full-stack role - roughly 80% backend, 20% frontend. You'll own features end to end: understanding customer problems, designing solutions, building and deploying them, and supporting them in production.
A key challenge on this team is building AI-native software customers can trust - turning customer intent into secure, observable, explainable, and repeatable production workflows.
We're looking for someone with 7+ years of backend/full-stack engineering experience, including time spent operating production systems, not just shipping them.
What You'll Do
Design and build backend services, APIs, and customer-facing capabilities across Sightline's product and platform - including conversational analytics, intelligent alerting, reports and saved analyses, and AI-powered/agentic workflowsOwn features end to end, from customer problem through to productionBuild reliable, asynchronous workflows with orchestration, error handling, recovery, and observability baked inIntegrate with data, analytics,



and AI model platformsDesign resilient systems that handle failures gracefullyContribute to the React frontend when a feature calls for itImprove testing, observability, security, and performance across the platformMake pragmatic technical decisions as the product evolves, and help shape engineering standards and architecture as we grow
What We're Looking For
You're a strong backend engineer who:
Has built and operated production SaaS productsIs comfortable contributing across the stackHas strong API, database, and SQL skillsUnderstands distributed systems, asynchronous processing, and failure modesCares about reliability, observability, security, and maintainabilityEnjoys owning features end to end and takes ownership of software beyond deploymentCan turn ambiguous customer problems into pragmatic technical solutionsUses AI-assisted development tools such as Claude Code, OpenAI Codex, or similar, while applying strong engineering judgement
Working at Longtail
We're a collaborative, distributed team that values transparency, ownership, clear communication, and sustainable ways of working. You'll have the autonomy to make meaningful technical decisions, the context to understand why your work matters, and the responsibility to see what you build succeed in production.
We're committed to building a respectful and inclusive workplace where people can do their best work.
Competitive Package with base + bonus + equity + Benefits (Private health insurance and Pension contribution, Learning and Development budget, Childcare, transport and meal vouchers…).
Interview Process
#J-18808-Ljbffr

📌 Senior Full-Stack Product Engineer (Barcelona)
🏢 Longtail Technologies
📍 Barcelona