Senior Software Engineer

Singular Aircraft; Valencia; Híbrido; EUR 65.000 - 70.000; Jornada completa

Descripción de la vacante

A leading technology startup is seeking a Senior Software Engineer to join their team in Valencia, Spain. You will help build and scale AI systems, working with TypeScript, Node.js, and AWS. The ideal candidate has significant experience in a fast-paced environment and a strong background in cloud technologies. This position offers a highly competitive salary, hybrid work options, and the opportunity to shape innovative solutions in healthcare.

Servicios

Highly competitive salary package

Health insurance plan

Hybrid setup: 1 day/week in Madrid

Ownership opportunities

Formación

• Strong experience with TypeScript, Node.js, React.
• Background in cloud architectures (AWS) and relational databases (Postgres).
• Experience in fast-paced startup environments.

Responsabilidades

• Build and scale backend services with TypeScript/Node.js, AWS, and Postgres.
• Collaborate with product and design to ship full-stack features.
• Ensure reliability and speed in systems that run at scale.

Conocimientos

TypeScript

Node.js

React

AWS

Postgres

English communication

Descripción del empleo

At Milu Health, our mission is to make healthcare affordable for millions of Americans. We receive real-time electronic health record data from consented patients, and we run that clinical data through a series of LLM agents to find ways we can proactively help patients get better quality and better value healthcare. When our agents find opportunities, our team of providers review every flagged intervention and SMS patients.

We’re an early-stage startup backed by a16z, already working with thousands of patients, growing 10x every 6 months — and we’re just getting started.

How we think about AI Engineering at Milu

Every technological wave has changed how software gets built. AI engineering is different: we’re not just building apps that people click on. We’re building autonomous agents that reason, plan, and take action.

At Milu, this means engineering AI-native systems that analyze medical data, orchestrate decisions, and surface savings automatically. Our engineering philosophy centers on multi-agent collaboration, real-time reasoning, and production-grade AI systems that deliver results.

Your role and purpose

As a Senior Software Engineer at Milu Health, you’ll be a founding member of our Madrid hub and help us scale our AI ecosystem. You’ll design and ship production-grade systems where LLM agents collaborate, connect to real-world data, and help people save on healthcare.

This is a role for someone who wants impact, ownership, and the thrill of building at the frontier of AI + healthcare.

What you’ll do

• Build and scale backend services with TypeScript/Node.js, AWS, and Postgres.
• Expand our ecosystem of AI agents: multi-agent orchestration, planning, reasoning, and intelligent tool-calling.
• Collaborate with product and design to ship full-stack features (Node.js + React).
• Ensure reliability, observability, and speed in systems that run at scale.
• Contribute to our engineering culture: small team, big impact, ownership-driven.

What we’re looking for

• Strong experience with TypeScript, Node.js, React.
• Background in cloud architectures (AWS) and relational databases (Postgres).
• Experience in fast-paced startup environments with small, high-performing teams.
• Great communication in English (our working language).

Nice to have:

• Experience with AI agents, LLM frameworks, or applied ML systems.
• Background in healthcare

What we offer

• Highly competitive salary package (65-70k€/year)
• Health insurance plan
• Hybrid setup: 1 day/week in Madrid office, rest remote.
• Work alongside a world-class team backed by a16z.
• Ownership opportunities: join early, shape foundations.
• The chance to change how millions of people access healthcare.

What happens after you apply?

Our Talent Acquisition team is invested in creating the best candidate experience possible, so don’t worry, you will definitely hear from us. We will review your CV and keep you posted by email at every step of the process!

Senior Software Engineer

Ayer

About Xebia

With over 20 years of experience, our global network of passionate technologists and pioneering craftsmen deliver cutting‑edge technology and game‑changing consulting to companies on the brink of transformation. Since 2001, we have grown from a Java company into a full-service digital consulting company with 5,500+ professionals working on a worldwide ambition.

We are organized in complementary service lines – teams with a tremendous amount of knowledge and experience within a particular field, such as Agile, DevOps, Data and AI, Cloud, Software Technology, Functional Programming, Intelligent Automation, and Microsoft.

We help the world’s top 250+ companies and category leaders overcome digital challenges, embrace innovation, adopt new technology, and implement new business models. In addition to high-quality consulting, we also provide offshoring and nearshoring services.

For more details, please visit

About the role

Software Engineer Identity Engineering - Level flexible based on experience

You will be part of the Identity Engineering team building Consumer Identity and Access Management systems for multiple brands and services.

You will design, build and support microservices in a multi region cloud environment.

Actively mentoring other engineers and collaborate across product, design and operations. For higher seniority levels you will lead architectural decisions and the technical roadmap.

What you will do:

• Design, develop, test, deploy and support stateful microservices and serverless components in a multi region cloud setup

• Contribute to or lead architectural decisions depending on seniority level

• Use Agile practices such as Scrum to plan work and drive continuous improvement

• Mentor engineers to grow their technical ability and visibility inside and outside the team

• Partner with Product Managers, Designers, QA and Operations to understand requirements and communicate technical decisions clearly

Required:

• 4+ years of experience with one Java Virtual Machine language as Scala and/or Java

• Experience with any major cloud provider AWS (main), GCP or Azure

Nice to have:

• Experience with both object oriented and functional programming approaches

• Experience with Terraform infrastructure as code and DevOps practices

Senior Software Engineer

Hoy

Pivotal is excited to expand our team and we are looking for an experienced, highly motivated Senior Software Engineer who shares our vision of providing clinical research excellence.

Joining Pivotal as a Senior Software Engineer means that you will enjoy being a member of one of the leading full-service contract research organizations in Europe with a very solid reputation. This role offers career growth and professional development within a scientific and data-driven company. You’ll have the opportunity to put your passion to work in an environment designed to help you gain experience in a wide variety of technologies.

Why Pivotal

• We are passionate and fully committed to medical science while using technology, to make a positive impact.
• We provide an exceptional experience. We take care of our employees, and we ensure everyone receives permanent mentoring and training and a push to always take one step further and untold international experience that will help you grow and will accompany all your life.
• We are continuously building the company, bringing together diversity of thoughts, backgrounds, cultures, and perspectives, being able to create a place where everyone feels like they belong.

Your responsibilities will include

• Manage multiple tasks simultaneously to meet deadlines.
• Perform complex analysis, designing and programming to meet business requirements.
• Maintain, manage and modify software systems and applications.
• Interface with end-users and software consultants.
• Develop, maintain and manage systems, software tools and applications.
• Resolve complex issues relating to business requirements and objectives.
• Coordinate and support internal and external software professionals in analysing and developing applications and tools.
• Analyse, develop and implement testing procedures, programming and documentation.
• Analyse, design and develop modifications and changes to existing systems to enhance performance.

Requirements

• A minimum of 5 years of experience as Senior Software Engineer.
• Experience working in frontend (REACT, TypeScript, Redux, Material UI).
• Backend frameworks experience (.Net Core/Standard) as a hands-on Technical Lead.
• Experience in DevOps, continuous integration, and continuous deployment.
• Experience in Agile Framework, Git, Visual Studio and Visual Code.
• Ensure development of best practices, components reusability.
• Experience in Task estimations of short and medium projects.
• Delivery ownership.
• University Degree in Computer Science, Engineering, Applied Mathematics, Life Sciences or related fields.

Skills

• Demonstrated problem-solving skills, a strong sense of urgency, keen attention to detail, and the ability to plan, organize and successfully execute in an environment under time and resource pressures.
• Strong written and verbal communication skills, attention to detail and ability to work in a fast-pace environment.
• Ability to work autonomously.
• Ability to work in multiple projects.
• Empathy and ability to establish good relationships with others.
• Fluency in English.

What you can expect

• Resources that promote your career growth.
• Leaders that support flexible work schedules.
• Training to help you build your knowledge.
• Dynamic work environments that expose you to new experiences.

Commitment to Equal Opportunity

At Pivotal, we believe that diversity and inclusion are essential to the success of our team. We are committed to providing equal employment opportunities to all candidates, regardless of race, gender, sexual orientation, disability, or any other characteristic.

Senior Software Engineer

Hoy

About Walkway

Walkway is on a mission to revolutionize the tours and activities industry with AI-driven revenue intelligence. We empower operators with data-rich insights, competitive benchmarking, and dynamic pricing solutions to help them stay ahead in a rapidly evolving travel landscape. As a Senior Software Engineer, you’ll play a pivotal role in building and enhancing our data-intensive SaaS platform, delivering real‑time analytics, automated pricing recommendations, and seamless user experiences.

About the Role

• Please note that we’re a US‑based company, so this position will be under a contractor agreement.

We’re hiring a Senior Software Engineer with a strong backend focus who can still navigate the full stack when needed. You’ll own core services (pricing, data ingestion, auth/permissions), shape our architecture, and partner with the founders on roadmap and trade‑offs. This role is ideal for a self‑starter who enjoys moving from design → code → production and can lead by example.

Beyond coding, you’ll drive engineering initiatives, collaborate with co‑founders, product and data teams, and support other developers. You’ll ensure our application remains performant and scalable as we handle large data sets, complex filtering logic, and real‑time updates for customers.

What You’ll Do

• Design and implement services in Node.Js/NestJS (TypeScript) running on GCP (Cloud Run, Cloud SQL/Postgres, Pub/Sub, Cloud Storage, VPC).
• Build and evolve multi‑tenant SaaS primitives: RBAC, org/workspace models, JWT/OAuth auth flows, API keys, rate‑limiting.
• Ship reliable REST (and/or GraphQL) APIs with versioning, pagination, idempotency, and strong contracts.
• Build background workers & schedulers for pricing jobs, data ingestion, and sync tasks (Pub/Sub/queues, cron).
• Performance engineering: caching strategies (e.g., Redis), query optimization, profiling, hot‑path tuning.
• Observability: metrics, tracing, structured logs (OpenTelemetry, Cloud Logging/Monitoring, Sentry).
• Secure by default: least‑privilege IAM, secrets management, encryption in transit/at rest, audit trails, PII handling, SOC2‑friendly habits.

2. Data & Integrations

• Integrate with OTA/partner APIs;
  design resilient adapters, retries, backoff, and data quality checks.
• Model data for analytics workloads;
  collaborate with data science on the pricing engine and evaluation loops.
• Co-drive the roadmap and architecture decisions (domain boundaries, service decomposition, buy vs. build).
• Set engineering standards, review PRs, mentor teammates, and unblock delivery.
• Balance velocity with reliability, cost, and long‑term maintainability

4. Performance and Scalability

• Optimize data‑fetching flows and caching strategies to minimize latency and network overhead.
• Identify bottlenecks in frontend or backend, propose architectural improvements, and ensure smooth scaling under high traffic.
• Collaborate with DevOps/Infrastructure teams for CI/CD, monitoring, and alerting setups; potentially work with Google Cloud, AWS, or Vercel.
• Lead engineering initiatives —work with the CTO and other senior engineers to define technical direction.
• Mentor other developers, conduct code reviews, and promote best practices in clean, testable code.
• Break down product requirements or complex technical tasks into achievable sprints, providing accurate estimates.

6. Frontend touchpoints (as needed)

• Contribute to Next.js/React endpoints/components when integration or contract changes require it.

Our stack (you don't need all of it)

• TypeScript, Node.Js, NestJS
• Next.Js/React (for UI)
• Terraform (nice to have), GitHub Actions, Sentry, OpenTelemetry

Requirements

• 6+ years building production software;
  at least 3+ years leading/owning backend services.
• Expert in Node.Js/TypeScript and a framework such as NestJS;
  strong SQL and Postgres fundamentals (modeling, indexing, migrations, locks, performance).
• Hands‑on GCP experience (or AWS/Azure with willingness to adopt GCP).
• Proven SaaS chops: RBAC, JWT/OAuth, API design, multi‑tenancy, background jobs, rate limiting, feature flags, A/B testing.
• Security & reliability mindset: secrets management, least‑privilege IAM, auditability, SLO/SLI thinking.
• Comfortable with CI/CD, Docker, and production debugging/observability.
• Clear communicator who enjoys owning problems end‑to‑end and participating in roadmap/architecture.

Nice to have

• Experience with pricing/revenue systems or marketplace dynamics.
• Data/ML adjacent experience (evaluation pipelines, offline/online experimentation).
• Experience with data stores beyond Postgres (BigQuery, DuckDB, Elasticsearch).
• Terraform/IaC, Kubernetes, or cost‑optimization on GCP.

Why Join Walkway

• Shape the Future of Travel : Influence architecture decisions on a high‑impact, AI‑driven SaaS platform (we recently won an Award!)
• Collaborative Culture : Work in a supportive, innovative environment that values continuous learning and open communication.
• Growth & Ownership : As a senior engineer, you’ll have the autonomy to guide projects from concept to production.

If you’re based in Europe, North America, or Latin America, don’t hesitate to reach out!