Resaro
Posted 2mo ago

Software Engineer

Resaro
Sofia, Sofia City, Bulgaria
OnsiteFull Time
Responsibilities
  • building APIs
  • maintaining infrastructure
  • mentoring engineers
Requirements
  • 3+ years software engineering experience
  • Strong Python and REST API (FastAPI) skills
  • Kubernetes, AWS, Git
  • Testing
  • System design, and production software lifecycle experience
Technical tools mentioned
PythonFastAPIKubernetesHelmReactTypeScriptNext.jsTerraformAWSGitCI/CDCUDA

Job description

About Us

Resaro was founded on the belief that AI will change the world in ways we cannot even imagine, but every new technology needs safeguards to advance.


Resaro builds custom AI testing software that helps organisations validate the performance, robustness, and safety of mission-critical AI systems - spanning computer vision, generative AI, and autonomous systems. Our clients include government, military, and commercial organisations deploying AI in high-stakes environments. We work through embedded teams deployed on-site or closely integrated with our clients.


We're looking for a Software Engineer to be a cornerstone of our AI platform. Our team of AI Engineers and Scientists produce world-class evaluation methodologies - your mission is to build the robust, scalable, and maintainable software that turns those ideas into production systems. This is a broad role: depending on your strengths and our needs, you may focus on backend services, frontend development, infrastructure/DevOps, or security. We track these as weightings, not separate titles.


What You'll Do:

  • Architect and build critical backend services and scalable APIs (Python/FastAPI) that power our AI assurance platform.
  • Own the full lifecycle of major platform components - from initial design through deployment, monitoring, and long-term maintenance.
  • Build and maintain the Kubernetes-based service orchestration infrastructure that underpins AIP, our core platform.
  • Develop responsive, data-rich UIs using React/TypeScript and modern frontend frameworks.
  • Manage CI/CD pipelines, infrastructure-as-code (Terraform), and Kubernetes environments for production and customer deployments.
  • Implement and maintain security practices: DevSecOps, secrets management, compliance (SOC 2, defence procurement).
  • Partner with AI Engineers and Product to translate complex evaluation requirements into pragmatic, robust technical solutions.
  • Write production-quality code with strong test coverage; mentor other engineers through code reviews and design discussions.
  • Identify and address technical debt proactively; improve platform reliability and maintainability over time.


What We're Looking For:

  • 3–7 years of professional software engineering experience shipping production systems.
  • Strong proficiency in Python, with hands-on experience building REST APIs (FastAPI or similar).
  • Experience with Kubernetes and container orchestration; comfort navigating complex multi-service architectures.
  • Solid engineering fundamentals: testing, code review, version control (Git), debugging, system design.
  • Experience with cloud platforms (AWS), including managed services for compute, storage, and databases.
  • Ability to work independently and manage ambiguity in a fast-moving startup environment.
  • Clear communicator who can translate technical complexity for non-technical stakeholders.


Nice to Have:

  • Experience with Kubernetes and Helm for production workloads.
  • Frontend skills: React, TypeScript, Next.js, component systems, data visualisation.
  • Infrastructure expertise: Terraform, CI/CD pipeline design, monitoring and observability.
  • Security background: application security, DevSecOps, compliance frameworks.
  • Familiarity with LLM integration, model serving, or ML-adjacent backend work.
  • GPU/CUDA infrastructure experience.
  • Experience working in defence, pharma, or other regulated industries.
  • Experience with air-gapped or on-premise deployment environments.


Our Hiring Blueprint:

We have deliberately tightened our hiring bar. Every engineer we bring on must meet these standards:

  • Production-grade code: You must demonstrate the ability to write clean, tested, maintainable code that ships to production, not just prototypes or notebooks.
  • Communication and handover: You must be able to clearly document your work, hand over context to colleagues, and communicate technical decisions to non-technical stakeholders.
  • Independent operation: You must be able to work autonomously with minimal supervision, manage ambiguity, and make sound technical decisions.
  • T-shaped profile: Depth in your primary area plus working knowledge across the stack. We value breadth alongside expertise.


Resaro is an Equal Opportunity Employer. We respect each individual and support the diverse cultures, perspectives, skills and experiences within our teams.

About Resaro

Independent third-party provider of AI model testing and assurance.

Year founded
2023
Employees
30
Organization type
Private
Latest investment
Corporate Round (2023) — led by Temasek
Headquarters
SG

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