Senior Backend Engineer (Remote)

Senior Backend Engineer (Remote)
Bucureşti
Bucharest, Bucharest, Romania

We act as a true HR Business Partner - providing tailored HR advisory while connecting the right talent with the right opportunities. Our focus is on delivering exceptional service and building
- term success for both businesses and candidates.

Recruiter4You is a brand operated by Consultant4You LTD a company based in Gibraltar

We are assisting one of our clients, a new exciting startup which is looking for a full remote:

Senior Backend Engineer

Responsibilities

• Architect, build, and optimize backend systems using Type
  Script, Nest
  JS, and Hono.
• Design and document scalable, secure APIs and microservices following Open
  API/Swagger standards.
• Build robust authentication & authorization frameworks:
  • JWT, OAuth2, API keys
  • RBAC/ABAC permissions
  • Session security & secure cookies
• Implement
  - level security patterns aligned with OWASP Top 10, including input validation, secure headers, CSRF/XSS mitigation, rate limiting, and safe error handling.
• Design performant, maintainable Mongo
  DB schemas; optimize queries, indexes, and aggregations.
• Work closely with Dev
  Ops to build cloud-native systems running on AWS EKS, with CI/CD, load balancing, and
  - scaling.
• Implement secure and optimized content delivery with AWS Cloud
  Front (signed URLs/cookies, CDN caching).
• Build
  - driven and distributed systems using queues/streams (Redis, Rabbit
  MQ, Kafka, SQS).
• Maintain documentation, enforce engineering standards, and lead backend code quality reviews.
• Troubleshoot production issues, optimize performance, and ensure system stability.
• Collaborate across teams (Product, Dev
  Ops, Frontend, Media Processing) to deliver
  - performance features.

Required Technical Skills
Backend Engineering

• Expert-level Type
  Script and experience building
  - scale backend systems.
• Deep expertise with Nest
  JS (guards, interceptors, pipes, modules, microservices).
• Strong
  - on experience with Hono for
  - performance edge/serverless routing.
• Strong knowledge of API architecture:
  • REST, Web
    Sockets, Graph
    QL
  • Open
    API/Swagger documentation
  • API versioning,
    - limits, pagination

Security & Authentication

• In-depth understanding of:
  • JWT, OAuth2, PKCE
  • RBAC/ABAC authorization
  • Input validation, sanitization
  • CORS, secure headers, HTTPS/TLS
  • OWASP Top 10 secure coding standards
• Ability to build secure-by-design backend systems in
  - risk environments.

Cloud Native & Dev
Ops

• Strong familiarity with AWS, specifically:
  • EKS, IAM, Cloud
    Front, API Gateway/ALB
  • Lambda, S3, Elasti
    Cache, SQS/SNS
• Understand containerized architecture (Docker), K8s deployments, autoscaling, and observability.
• Experience creating
  - availability,
  - tolerant,
  - optimized backend systems.
• Experience with Cloudflare is a plus.

Data & Distributed Systems

• Strong Mongo
  DB expertise: indexing, aggregations, schema design, sharding (advantage).
• Experience with distributed caching and queueing systems:
  • Redis, Rabbit
    MQ, Kafka, SQS
• Experience with media-heavy systems, file processing, and content delivery.