> Markdown version of [/jobs/ext/4056735-medior-software-developer](https://www.wearedevelopers.com/jobs/ext/4056735-medior-software-developer). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Medior Software Developer - **Company:** Postalia Belgium NV - **Location:** Brussel, Belgium (Remote available) - **Experience:** Experienced - **Contract:** Permanent contract - **Skills:** Microsoft Word, JavaScript (Programming Language), Application Programming Interfaces (APIs), Amazon Web Services, Amazon S3, Audit Trail, Automation of Tests, Cloud Engineering, Software Quality, Code Review, Continuous Integration, Distributed Systems, Amazon DynamoDB, Elasticsearch, NoSQL, E2e Testing, TypeScript, Extensible Markup Language (XML), AWS Cdk, Cloud Platform System, Bitbucket Pipelines, ReactJS, State Machines, AWS Lambda, Backend, Servicebus, Event Driven Architecture, Integration Frameworks, Front End Software Development, Cloudwatch, Api Gateway, NestJS, Restful APIs, Amazon Simple Queue Service (SQS), Webhooks, Serverless Computing, OpenSearch - **Published:** October 8, 2026 - **Apply:** https://www.indeed.com/viewjob?jk=06588e3995106ea4 ## About the Role * Professional experience building and maintaining production software. * Good TypeScript and Node.js skills. * Experience with AWS or another major cloud platform. * Some practical experience with serverless or event-driven applications. * The ability to implement features from a technical design and contribute constructively to design discussions. * Familiarity with concepts such as idempotency, retries, queues, dead-letter queues and eventual consistency. * Experience building REST APIs or third-party integrations. * Familiarity with infrastructure as code, preferably AWS CDK. * Experience with automated testing, code review and CI/CD. * A security-conscious approach to personal data, credentials and permissions. * The ability to investigate production issues methodically and ask for help when appropriate. * Clear English communication and the ability to work effectively with engineering and product colleagues. * A sense of ownership for the quality and production behaviour of the features you build. * The motivation to deepen your technical knowledge and grow towards broader engineering responsibility. Useful additional experience * NestJS. * React or Ant Design. * Nx monorepositories. * DynamoDB or other NoSQL databases. * OpenSearch or Elasticsearch. * Bitbucket Pipelines. * Multi-account AWS environments. * PDF, Word, XML or UBL document processing. * Peppol, e-invoicing, e-signatures or registered electronic delivery. * Maintaining or modernising an existing production platform. You do not need prior experience with all these technologies or with our specific document-delivery channels. We care about solid engineering fundamentals, curiosity and the ability to learn unfamiliar systems and business domains. What you can expect * Ownership of meaningful production features. * Guidance and technical support from experienced engineers and the team lead. * Practical experience with AWS, event-driven architecture and external integrations. ## Description Our customers use EasyPost to send invoices and business documents through channels such as Peppol e-invoicing, Belgian eBox, electronic registered delivery, e-signing, email and print. Behind this experience is a large event-driven AWS platform that processes sensitive documents, integrates with external providers and coordinates long-running delivery workflows. Your role You will develop features across our TypeScript backend and AWS serverless platform, from implementation and testing through deployment and production support. This role focuses on frontend, backend and cloud engineering. You will work closely with senior engineers, our team lead, product management and other developers to turn business requirements into secure, reliable and maintainable solutions. You will take ownership of clearly scoped features while continuing to strengthen your knowledge of cloud architecture, distributed systems and production operations. What you will do * Develop and maintain TypeScript services, AWS Lambda functions and NestJS APIs. * Build and update serverless infrastructure using AWS CDK. * Turn business requirements and technical designs into working software. * Contribute to technical designs and architectural discussions with support from senior engineers. * Build event-driven workflows that correctly handle retries, duplicate events, timeouts and partial failures. * Integrate with external e-invoicing, e-delivery and e-signing providers through APIs and webhooks. * Work with AWS services such as Lambda, DynamoDB, EventBridge, SQS, Step Functions, API Gateway, S3 and CloudWatch. * Apply established security practices for encryption, permissions, credentials, audit logging and sensitive data. * Write unit, integration and end-to-end tests using Jest. * Monitor services in production and investigate issues in application code, AWS infrastructure and external integrations. * Participate in code reviews and apply feedback to improve code quality and maintainability. * Contribute to improvements in our development, CI/CD and deployment processes. * Collaborate with frontend engineers to deliver complete and reliable user journeys. * Share knowledge with colleagues and gradually take ownership of larger and more complex features.