Yojji

We are looking for a Backend Engineer to join a planned data and services migration project.
The main focus of the role is migrating data from MongoDB to PostgreSQL and rewriting part of the backend services.

This is not a firefighting role, but a structured technical migration with a clear scope and team support.

Responsibilities

• Participate in the migration of data from MongoDB to PostgreSQL
• Rewrite and adapt backend services using NestJS
• Translate MongoDB aggregation logic into SQL-based solutions
• Work with relational data models and transactions
• Optimize queries and data-related computations

• Collaborate with the team on migration-related technical decisionsTech Stack (Core)

  • Node.js 18+, TypeScript
  • react, socket.io
  • NestJS (modules, controllers, services, DI)
  • MongoDB + Mongoose
  • PostgreSQL
  • TypeORM
  • REST APIs, DTOs, validation

  Requirements

  • Commercial experience with Node.js and TypeScript
  • Strong knowledge of MongoDB, including aggregation pipelines
  • Good understanding of relational databases and SQL
  • Careful and accurate work with data and computations
  • Basic understanding of backend security (JWT, roles, permissions)
  • English level: Upper-Intermediate (sufficient for daily communication).
    Nice to Have (Not Required)
    • Experience with NestJS guards, pipes, interceptors
    • Redis, background jobs, or queues
    • Previous experience with database migrations
    • Neo4j or real-time features (Socket.IO)
    • Experience using AI-assisted tools (e.g. Claude Code)

Yojji is a development center, based in Europe. We are a team of specialists with great experience in JavaScript, full-stack development and web design. We provide outsource and outstaff services to reliable frequent customers and startups in the USA, Europe and Israel.