We're data-driven and never stop iterating. If you'd like to work in a supportive, entrepreneurial environment, are interested in building something meaningful and having fun while doing it, we'd love to hear from you.
You care more about solutions and impacting the customer experience than using a particular tool or framework.
Instead of writing bespoke software for every workflow, we are developing an agent platform that can read operational knowledge, reason about it in context, and execute tasks end-to-end. The work spans critical areas including LLM-powered agent design, robust backend service architecture, tool and integration development, and sophisticated knowledge infrastructure.
We are seeking a Senior Software Engineer with a strong passion for building AI-native systems in a product environment. The idóneo candidate will be able to take ownership of large segments of the technology stack, make pragmatic technical decisions in ambiguous and emerging territory, and consistently ship high-quality, production-ready systems that our users rely on every day.
Design, build, and own core components of the agent platform, from the orchestration layer to the tool integrations connecting it to internal systems.
APIs, data access patterns, and service integrations for agents to execute operational workflows.
Architect the knowledge and memory infrastructure, allowing agents to retrieve the data and act across our systems.
Design and implement the trust and safety framework, including audit trails, human-in-the-loop controls,



and guardrails for safe and auditable AI-driven operations.
Contribute to agent evaluation and testing infrastructure, defining how we measure accuracy, reliability, and regression across agent behaviors.
Mentor other engineers on the team as it grows.
You are comfortable in a fast-paced, early-stage environment. You are pragmatic and balance quality with speed. You prioritize pragmatism over being overly precious about code, but never compromise on quality in a way that creates future issues.
You look beyond the immediate task, seeking to understand the "why" behind the build and questioning whether it's the right product solution. You possess strong backend engineering fundamentals. 5+ years of backend engineering experience building and operating production systems
~ Proven ownership of complex projects in ambiguous, early-stage environments

Golang, Ruby on Rails, Javascript, Java, C#, Python, VueJS, MySQL, Kafka, AWS, Git, Memcache, Redis, ElasticSearch, Docker, Terraform, Kubernetes, CircleCI, DataDog

We're proud to be an equal opportunity employer open to all qualified applicants regardless of race, color, ancestry, religion, sex, national origin, sexual orientation, age, citizenship, marital or familial status, disability, pregnancy, gender identity or expression, veteran status, genetic information, or any other legally protected status. We also provide reasonable accommodations to employees based on their sincerely held religious beliefs, as well as for other covered reasons consistent with applicable federal, state, and local laws.

📌 Senior AWS Software Engineer (España)
🏢 Justworks
📍 España