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Backend Engineer (Fixed-term contract) Technical · Madrid, Barcelona

Multiverse Computing

Multiverse Computing

Software Engineering, IT
Madrid, Spain · Barcelona, Spain
EUR 45k-45k / year
Posted on Nov 8, 2025
Technical · Madrid, Barcelona

Backend Engineer (Fixed-term contract)

We are looking to fill this role immediately and are reviewing applications daily. Expect a fast, transparent process with quick feedback.

Why join us?

We are a European deep-tech leader in quantum and AI, backed by major global strategic investors and strong EU support. Our groundbreaking technology is already transforming how AI is deployed worldwide — compressing large language models by up to 95% without losing accuracy and cutting inference costs by 50–80%.
Joining us means working on cutting-edge solutions that make AI faster, greener, and more accessible — and being part of a company often described as a “quantum-AI unicorn in the making.”

We offer

  • Competitive annual salary starting from €45,000, based on experience and qualifications.
  • Two unique bonuses: signing bonus at incorporation and retention bonus at contract completion.
  • Relocation package (if applicable).
  • Fixed-term contract ending in June 2026.
  • Hybrid role and flexible working hours.
  • Be part of a fast-scaling Series B company at the forefront of deep tech.
  • Equal pay guaranteed.
  • International exposure in a multicultural, cutting-edge environment.

Required Qualifications

  • 2–5 years of experience developing and maintaining backend systems in Python or Go.
  • Strong understanding of RESTful API or gRPC design, versioning, and performance optimization.
  • Experience with Docker and basic familiarity with Kubernetes for deploying scalable services.
  • Solid understanding of relational databases (PostgreSQL/MySQL) and schema design.
  • Experience integrating or automating workflows across multiple systems (data, CI/CD, ML).
  • Proficiency with Git, testing frameworks, and CI/CD pipelines (GitLab, GitHub Actions).
  • Experience with AWS or cloud-based deployment environments.
  • A product-oriented mindset — able to turn R&D scripts or prototypes into stable, usable APIs or microservices.

Preferred Qualifications

  • Experience with ML workflow orchestration (Flyte, Airflow, MLflow, or Kubeflow).
  • Exposure to LLM inference/deployment tools (vLLM, Hugging Face Hub, NVIDIA NIM, or Triton).
  • Experience building or integrating benchmarking, evaluation, or data automation pipelines.
  • Familiarity with message queues or event-driven architectures (Kafka, NATS, RabbitMQ).
  • Understanding of observability tooling (Prometheus, Grafana, OpenTelemetry).
  • Demonstrated ability to collaborate with product and design teams to define backend contracts that enable intuitive user experiences.

About Multiverse Computing

Founded in 2019, we are a well-funded, fast-growing deep-tech company with a team of 180+ employees worldwide. Recognized by CB Insights (2023 & 2025) as one of the Top 100 most promising AI companies globally, we are also the largest quantum software company in the EU.
Our flagship products address critical industry needs:

  • CompactifAI → a groundbreaking compression tool for foundational AI models, reducing their size by up to 95% while maintaining accuracy, enabling portability across devices from cloud to mobile and beyond.
  • Singularity → a quantum and quantum-inspired optimization platform used by blue-chip companies in finance, energy, and manufacturing to solve complex challenges with immediate performance gains.

You’ll be working alongside world-leading experts in quantum computing and AI, developing solutions that deliver real-world impact for global clients. We are committed to an inclusive, ethics-driven culture that values sustainability, diversity, and collaboration — a place where passionate people can grow and thrive. Come and join us!

Department
Technical
Role
Software Engineer
Locations
Madrid, Barcelona
Employment type
Contract
Workplace type
Hybrid
Seniority level
Associate

About MULTIVERSE COMPUTING

Come and join our multicultural team!

5 locations
+27 languages

Founded in 2019
Coworkers +150
Technical · Madrid, Barcelona

Backend Engineer (Fixed-term contract)

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