Senior Full-Stack Product Engineer

Longtail Technologies; Barcelona; Presencial; EUR 70.000 - 110.000; Jornada completa

Ventajas ofrecidas por este puesto de trabajo

Private health insurance

Pension contribution

Learning & Development budget

Childcare support

Transport and meal vouchers

Descripción de la vacante

Longtail Technologies is building Sightline, an intelligent analytics and alerting product. This backend-focused role owns features end to end—from understanding customer problems to deployment and production support.

You will design reliable systems, integrate with data and AI platforms, and occasionally contribute to the frontend. Emphasis on reliability, observability, and secure, scalable software.

Formación

• 7+ years of backend/full-stack engineering experience.
• Experience building production SaaS products.
• Strong API, database, and SQL skills.
• Understanding of distributed systems, asynchronous processing, and failure modes.
• Cares about reliability, observability, security, and maintainability.

Responsabilidades

• Design and build backend services, APIs, and analytics features across Sightline.
• Own features end to end from problem to production.
• Build reliable, asynchronous workflows with observability baked in.
• Integrate with data, analytics, and AI model platforms.
• Contribute to React frontend when a feature calls for it.
• Improve testing, observability, security, and performance across the platform.

Conocimientos

Backend engineering

Full-stack

API design

Databases

Distributed systems

Herramientas

Java

Spring Boot

Python

FastAPI

PostgreSQL

Kubernetes

AWS

Terraform

OpenTelemetry

Descripción del empleo

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.

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. 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 workflows
• Own features end to end, from customer problem through to production
• Build reliable, asynchronous workflows with orchestration, error handling, recovery, and observability baked in
• Integrate with data, analytics, and AI model platforms
• Design resilient systems that handle failures gracefully
• Contribute to the React frontend when a feature calls for it
• Improve testing, observability, security, and performance across the platform
• Make pragmatic technical decisions as the product evolves, and help shape engineering standards and architecture as we grow

Our Tech Stack

Backend: Java, Spring Boot, Python, FastAPI, MCP

Frontend: React, Vite, Zustand, Vitest, Nginx

AI & Data: Anthropic, OpenAI, OpenRouter, Databricks, PostgreSQL, Amazon Aurora

Infrastructure: AWS, Kubernetes, Docker, Terraform, Kong, Keycloak, OpenTelemetry, New Relic

What We're Looking For

You're a strong backend engineer who:

• Has built and operated production SaaS products
• Is comfortable contributing across the stack
• Has strong API, database, and SQL skills
• Understands distributed systems, asynchronous processing, and failure modes
• Cares about reliability, observability, security, and maintainability
• Enjoys owning features end to end and takes ownership of software beyond deployment
• Can turn ambiguous customer problems into pragmatic technical solutions
• Uses AI-assisted development tools such as Claude Code, OpenAI Codex, or similar, while applying strong engineering judgement

Nice to have

experience with AI-native products, LLM applications, agents, or workflow orchestration; and/or experience in analytics, enterprise SaaS, pricing, travel, or aviation. Experience building AI agents is a plus, but strong engineering fundamentals matter more.

What Success Looks Like

Within your first few months, you'll:

• Ship a meaningful customer-facing capability
• Take ownership of a defined area of Sightline
• Improve the reliability or observability of an existing workflow
• Build a strong understanding of our architecture and customer needs

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.

Compensation & Benefits

Competitive Package with base + bonus + equity + Benefits (Private health insurance and Pension contribution, Learning and Development budget, Childcare, transport and meal vouchers ...)

Interview Process

Intro call - Technical interview - System Design - AI-Assisted Coding Interview - Behavioural interview - Offer.

Ready to Build Something That Matters?

If you want to build AI-powered products that turn complex airline data into better commercial decisions - and solve the engineering challenges required to make AI reliable at enterprise scale - we'd love to meet you.

We may use artificial intelligence (AI) tools to support parts of the hiring process, such as reviewing applications, analyzing resumes, or assessing responses and identifying potential inconsistencies or verification signals in application materials based on available information. These tools assist our recruitment team but do not replace human judgment. Final hiring decisions are ultimately made by humans. If you would like more information about how your data is processed, please contact us.