Senior Node.js Developer

🏢 Summary: Senior Backend Node.js Developer role focused on building and scaling an event-driven microservices trading platform. The position involves end-to-end development within a distributed architecture, ensuring high performance, scalability, and code quality. Fully remote B2B contract with overlap with NYC hours. 🗂️ Requirements: 4+ years web application development experience, Expert knowledge of Node.js, Expert knowledge of TypeScript, Experience with distributed systems architecture, Experience with Apache Kafka, Experience with Redis, Experience with Kubernetes, Experience with MongoDB, Experience with automated unit testing and TDD, Strong understanding of performance optimization and computational complexity, Knowledge of algorithms and design patterns, Broad knowledge of web technologies 📃 Skills: Node.js, TypeScript, Kafka, Redis, Kubernetes, MongoDB, Microservices, TDD, Algorithms, DesignPatterns, Web 🏢 Description: We are looking for a performance-driven backend Senior Node.js Developer who can help us bring our client's trading solutions to the next level of functionality, scalability, and user experience. They are actively developing a new event-driven microservices architecture to form a foundational platform for delivering new trading applications. You will be responsible for delivering software end-to-end , from liaising with product managers and designers, to coordinating across international development teams on engineering and architecture to working with QA and DevOps teams - all ultimately to deliver a quality, innovative product to the traders and investors who depend on the platform every day. Requirements: Fluent English language [both written and spoken] Education: at least Bachelor's Degree, preferably in Computer Science 4+ years' professional web application development experience Expert-level Node.js and TypeScript knowledge, and curiosity to learn more Broad knowledge of web platform and technologies Superior analytical and problem-solving ability Effective communication skills to work with different teams across an international company Experience with modern distributed systems and infrastructure technologies, including Apache Kafka, Redis, Kubernetes, and MongoDB Automated unit testing and test-driven development Robust understanding of performance issues, computational complexity, and code optimization. Familiarity and implementation of industry-standard algorithms and design patterns Proactive and team player who can deliver in a high-pressure demanding environment Nest.js – nice to have Offer details: 100% remote job preferrably at least 4-5 hours overlap with NYC working hours B2B contract rate up to 55 USD/h net

🏢 Summary: Fully remote Senior Node.js Backend Engineer role focused on building and scaling cloud-native microservices in a serverless AWS environment. The position involves designing high-performance REST APIs, provisioning infrastructure with Terraform, and optimizing distributed systems for scalability and resilience. You will contribute to CI/CD pipelines and ensure robust, production-grade backend services. 🗂️ Requirements: 4+ years of professional experience in Node.js server-side development, 2+ years of experience in system and data integration, transformation, and validation, Strong experience designing and deploying REST APIs, Hands-on experience with Terraform for AWS infrastructure provisioning, Practical experience with AWS services: Lambda, SQS, CloudWatch, S3, Deep understanding of distributed systems, scalability, and failure handling, Experience with CI/CD pipelines and GitHub Actions, Proficiency with shell scripting and Linux command-line tools 📃 Skills: Node.js, AWS, Lambda, SQS, CloudWatch, S3, Terraform, REST, CICD, GitHubActions, Shell, Linux, DistributedSystems, DynamoDB, DocumentDB, Streaming 🏢 Description: Ignite innovation at the forefront of cloud-native backend development — shape scalable microservices for dynamic digital ecosystems. Fully-remote opportunity! As a Senior Node.js Backend Engineer , you will be working for our client, a leading technology-driven organization dedicated to building resilient distributed systems that power tomorrow's digital experiences. You will contribute to designing and implementing high-performance microservices on AWS, enhancing system robustness, scalability, and flexibility. Join us and be part of pioneering solutions that redefine industry standards and accelerate your career growth. Your main responsibilities: Develop and maintain REST-like APIs and backend services using Node.js in a serverless AWS environment Design, implement, and optimize infrastructure-as-code configurations with Terraform for AWS services such as Lambda, SQS, CloudWatch, and S3 Integrate complex data streams, transform, validate, and analyze data within distributed systems Collaborate with cross-functional teams to ensure system robustness, scalability, and failure resilience Contribute to CI/CD pipelines utilizing GitHub Actions, and enforce best practices in version control Troubleshoot and resolve operational issues within AWS infrastructure and backend services Maintain comprehensive documentation and ensure high-quality code standards You're ideal for this role if you have: At least 4 years of professional experience in Node.js server-side development 2+ years of experience in system/data integration, transformation, and validation Deep understanding of distributed systems, including scalability, elasticity, replication, and failure handling Strong experience designing and deploying REST-like APIs Hands-on experience with Terraform for AWS infrastructure provisioning Practical knowledge of serverless AWS services: Lambda, SQS, CloudWatch, S3 Solid grasp of GitHub tool suite, CICD pipelines, and shell scripting Good command of Linux command line tools Excellent communication skills in English Problem-solving mentality with a focus on business impact It is a strong plus if you have: Experience with DynamoDB, DocumentDB, and Streaming services Language Required for the role: Fluent English Eligibility for the role: Only candidates with an existing legal right to work in the European Union will be considered for this role. We offer you At ITDS , you will work on innovative and impactful technology projects for international companies across multiple industries in Europe and beyond. We create an environment for ambitious, driven professionals who want to grow, deliver value, and build their careers in modern IT and digital transformation. Our offer includes: Stable and long-term cooperation with attractive conditions Opportunities to develop your technical expertise across various industries and technologies The chance to work on high-impact, strategic IT and digital transformation projects A clear career path and the opportunity to grow quickly by contributing to diverse client initiatives over time International environment , knowledge sharing, social events, and training opportunities Access to an attractive medical package Access to the Multisport program Access to learning platforms such as Pluralsight Flexible working hours and remote work options #MAKEYourCareerBETTER Interested? Apply now and include your CV (preferably in English) along with a statement confirming your consent to the processing and storage of your personal data. # 8942

🏢 Summary: B2B contract role for a Mid/Senior Node.js Developer focused on building and maintaining backend systems such as SaaS platforms, cloud-native applications, microservices, and event-driven architectures. The position involves architectural decision-making, backend development, and close collaboration with QA and DevOps in international projects. Candidates will work with modern cloud environments and have real impact on system design and product development. 🗂️ Requirements: 4+ years of backend development experience, Strong knowledge of Node.js, Experience with TypeScript or JavaScript, Experience with SQL databases, Experience with NoSQL databases, Understanding of microservices architecture, Understanding of serverless architecture, Understanding of event-driven systems, Hands-on experience with GCP, AWS, or Azure, Ability to write clean and maintainable code, Experience with unit and integration testing, English level minimum B2 📃 Skills: Node.js, TypeScript, JavaScript, SQL, NoSQL, GCP, AWS, Azure, REST, Docker, Microservices, Serverless, Testing 🏢 Description: We are a software house delivering long-term projects for international clients , and we are looking for Mid / Senior Node.js Developers to join our team on a B2B contract . You will work on various backend-focused projects , such as SaaS platforms, cloud-native systems, microservices, and event-driven architectures. We match projects to your experience and technical preferences, and you will have a real impact on architecture and product development. Responsibilities design, develop, and maintain backend services using Node.js (TypeScript / JavaScript) implement new features and improve existing functionalities participate in technical and architectural decision-making refactor and optimize key components of the system ensure code quality through clean code practices and testing collaborate closely with developers, QA, and DevOps engineers Requirements 4+ years of experience in backend development strong knowledge of Node.js (TypeScript / JavaScript) experience with SQL and NoSQL databases good understanding of cloud-based architectures (microservices, serverless, event-driven systems) hands-on experience with at least one cloud provider ( GCP, AWS, or Azure ) ability to write clean, well-structured, and maintainable code proactive mindset and willingness to grow technically good communication skills and English level min. B2B Example Tech Stack (depends on the project) Node.js / TypeScript Cloud platforms: GCP, Azure or AWS REST APIs & asynchronous communication SQL & NoSQL databases Docker Unit and integration testing

🏢 Summary: Senior Node.js Developer role focused on building and scaling the backend API layer of an IoT platform for monitoring and optimizing energy usage in buildings. The position involves developing distributed backend systems using TypeScript, Node.js, and Kubernetes, and integrating with IoT devices and analytics modules. The role requires delivering high‑performance, scalable solutions in a cloud-based environment. 🗂️ Requirements: Minimum 5 years of commercial backend development experience, Strong knowledge of Node.js, Strong knowledge of TypeScript, Understanding of distributed systems, Experience with scalable backend design, Experience with containerized or cloud environments, Experience with Kubernetes, Ability to work in Agile environment, Fluency in English, Residing in Poland 📃 Skills: Node.js, TypeScript, Kubernetes, IoT, APIs, Backend, Cloud, DistributedSystems, Agile 🏢 Description: We are looking for a Senior Node.js Developer to join a project for a leading global energy‑tech company. You will help build an intelligent platform used to monitor and optimize energy usage in buildings. The work combines backend development, IoT integration, and modern cloud technologies. Your tasks Develop backend applications that provide the API layer of the IoT platform using TypeScript and Node.js Build and maintain backend services supporting mobile and web solutions Use Node.js, TypeScript, and Kubernetes to deliver reliable and scalable systems Integrate backend features with IoT devices, analytics modules, and other platform components Ensure high performance, clean architecture, and smooth cooperation with other teams Requirements Minimum 5 years of commercial experience in backend development Strong knowledge of Node.js and TypeScript Understanding of distributed systems and scalable backend design Experience with containerized or cloud‑based environments (e.g., Kubernetes) Ability to work in an Agile environment and deliver high‑quality code Fluency in English Residing in Poland required

🏢 Summary: Senior Node.js Developer role focused on building and maintaining distributed backend systems for digital advertising and identity management using Node.js and NestJS. The position involves full lifecycle development, performance optimization, automated testing, and monitoring within a non-monolithic architecture. It also includes contributing to R&D initiatives to evolve the advertising ecosystem. 🗂️ Requirements: Higher education in Computer Science or related field, Minimum 5 years of programming experience, At least 5 years of Node.js development experience, Experience in backend application design, Experience in performance optimization, Experience in application monitoring, Experience with distributed (non-monolithic) architecture, Proficiency in automated testing development, Very good knowledge of Node.js and TypeScript, Very good knowledge of NestJS or Fastify, Experience with MongoDB and Redis, Experience with AWS S3, Knowledge of object-oriented and functional JavaScript, Experience in event-driven development, Knowledge of design patterns and best practices, Experience with Git and GitHub, English proficiency for technical documentation 📃 Skills: Node.js, TypeScript, NestJS, Fastify, MongoDB, Redis, AWS, S3, JavaScript, GIT, GitHub, Babel, Jest, Jasmine, Karma, Cypress, Datadog, Jenkins, Unix, Bash, React, NoSQL 🏢 Description: Shape the Future of Digital Advertising as a Senior Node.js Developer! Krakow/Warsaw-based opportunity with almost fully remote work model (1 day in the office/month). As a Senior Node.js Developer you'll be working for our client, a prominent player in the media industry. You will join the team and take responsibility for the development and maintenance of backend applications (Node.js, NestJS) in the field of digital advertising serving technologies and identity management, built in a distributed (non-monolithic) architecture. We are seeking someone actively engaged in improving the quality of solutions and processes, including the development of automated tests and monitoring tools, as well as co-creating new directions for the development of the advertising ecosystem (R&D). Your main responsibilities: Develop and maintain backend applications (Node.js, NestJS) for digital advertising serving and identity technologies. Develop and maintain automated tests (tools and test cases). Develop and maintain monitoring solutions. Actively participate in creating new solutions and development directions for the advertising ecosystem (R&D). Participate in the full software development lifecycle: from requirements clarification, through design, implementation, deployment, to maintenance and monitoring. You're ideal for this role if you have: Higher education, preferably in Computer Science. Minimum 5 years of programming experience in IT projects. At least 5 years of experience in Node.js project development. Experience in application design, performance optimization, and monitoring. Ability to decompose tasks effectively. Very good knowledge of: Node.js, TypeScript Frameworks such as NestJS, Fastify Databases: MongoDB, Redis AWS S3 bucket Object-oriented and functional programming in JavaScript Event-driven development Design patterns and best practices Version control systems: GIT, GitHub Babel tools Willingness for active professional growth English language skills sufficient for reading/writing technical documentation Nice to have: Knowledge of digital/programmatic advertising Familiarity with React.js and NoSQL databases Comfortable working in Unix environments, including writing bash scripts Experience with Jenkins Familiarity with Agile / Scrum / KANBAN methodologies Experience with Datadog Familiarity with test frameworks like Jest, Jasmine, Karma, Cypress Ability to write unit, functional, and integration tests

🏢 Summary: Senior Node.js Developer role focused on building and maintaining distributed backend systems for digital advertising and identity management. The position involves full lifecycle development, automated testing, monitoring, and performance optimization using Node.js and related technologies. The role is almost fully remote with occasional office presence in Krakow or Warsaw. 🗂️ Requirements: Higher education in Computer Science or related field, Minimum 5 years of programming experience, At least 5 years of commercial experience with Node.js, Strong knowledge of Node.js and TypeScript, Experience with NestJS or Fastify frameworks, Experience with MongoDB and Redis, Experience with AWS and S3, Experience in application design and performance optimization, Experience in building automated tests and monitoring solutions, Knowledge of event-driven architecture and design patterns, Proficiency with Git and GitHub, Good command of technical English 📃 Skills: Node.js, TypeScript, NestJS, Fastify, MongoDB, Redis, AWS, S3, JavaScript, Git, GitHub, Babel 🏢 Description: Shape the Future of Digital Advertising as a Senior Node.js Developer! Krakow/Warsaw-based opportunity with almost fully remote work model (1 day in the office/month). As a Senior Node.js Developer you'll be working for our client, a prominent player in the media industry. You will join the team and take responsibility for the development and maintenance of backend applications (Node.js, NestJS) in the field of digital advertising serving technologies and identity management, built in a distributed (non-monolithic) architecture. We are seeking someone actively engaged in improving the quality of solutions and processes, including the development of automated tests and monitoring tools, as well as co-creating new directions for the development of the advertising ecosystem (R&D). Your main responsibilities: Develop and maintain backend applications (Node.js, NestJS) for digital advertising serving and identity technologies. Develop and maintain automated tests (tools and test cases). Develop and maintain monitoring solutions. Actively participate in creating new solutions and development directions for the advertising ecosystem (R&D). Participate in the full software development lifecycle: from requirements clarification, through design, implementation, deployment, to maintenance and monitoring. You're ideal for this role if you have: Higher education, preferably in Computer Science. Minimum 5 years of programming experience in IT projects. At least 5 years of experience in Node.js project development. Experience in application design, performance optimization, and monitoring. Ability to decompose tasks effectively. Very good knowledge of: Node.js, TypeScript Frameworks such as NestJS, Fastify Databases: MongoDB, Redis AWS S3 bucket Object-oriented and functional programming in JavaScript Event-driven development Design patterns and best practices Version control systems: GIT, GitHub Babel tools Willingness for active professional growth English language skills sufficient for reading/writing technical documentation Nice to have: Knowledge of digital/programmatic advertising Familiarity with React.js and NoSQL databases Comfortable working in Unix environments, including writing bash scripts Experience with Jenkins Familiarity with Agile / Scrum / KANBAN methodologies Experience with Datadog Familiarity with test frameworks like Jest, Jasmine, Karma, Cypress Ability to write unit, functional, and integration tests

🏢 Summary: Senior Node.js Developer role focused on building and maintaining backend systems for digital advertising and identity management within a distributed architecture. The position involves full lifecycle development, performance optimization, monitoring, and R&D initiatives in a hybrid or remote model. The role requires strong expertise in Node.js and related technologies to deliver scalable, high-performance solutions. 🗂️ Requirements: Higher education in Computer Science or related field, Minimum 5 years of professional programming experience, Minimum 5 years of hands-on Node.js experience, Strong knowledge of application design and performance optimization, Experience with backend frameworks (NestJS or Fastify), Experience with MongoDB and Redis, Experience with AWS services (including S3), Knowledge of event-driven architecture and design patterns, Experience with Git and GitHub, Experience working in Unix environments and Bash scripting, Good command of English (technical documentation), Communicative Polish, Legal right to work in the European Union 📃 Skills: Node.js, TypeScript, NestJS, Fastify, MongoDB, Redis, AWS, S3, JavaScript, Git, GitHub, Bash, Unix, Babel, OOP, FP, EventDriven, DesignPatterns, Monitoring, Testing, Polish, English 🏢 Description: Unleash the Future of Digital Advertising — Elevate Backend Architectures with Cutting-Edge Node.js Solutions! Krakow/Warsaw-based opportunity with almost fully remote work model (only 1 day in the office/month). As a Senior Node.js Developer , you will be working for our client, a leading innovator in the media industry. You will join a dynamic team dedicated to advancing digital advertising technologies, focusing on backend development and identity management in a distributed, non-monolithic architecture. This role offers a chance to influence the evolution of advertising ecosystems through innovation and R&D initiatives, fostering your professional growth in a fast-paced environment. Your main responsibilities: Develop and maintain backend applications (Node.js, NestJS) for digital advertising serving and identity technologies. Develop and maintain automated tests (tools and test cases). Develop and maintain monitoring solutions to ensure system reliability. Actively participate in creating new solutions and shaping development directions (R&D) within the advertising ecosystem. Participate in the full software development lifecycle: from requirements clarification, through design and implementation, to deployment, maintenance, and monitoring. You're ideal for this role if you have: Minimum of 5 years of programming experience in IT projects. At least 5 years of experience in Node.js project development. Strong knowledge of application design, performance optimization, and system monitoring. Proficiency in Node.js, TypeScript, NestJS, Fastify. Experience with MongoDB, Redis, AWS S3. Ability to decompose tasks effectively and work collaboratively. Good understanding of object-oriented and functional programming in JavaScript. Familiarity with event-driven development, design patterns, and best practices. Experience with version control systems: GIT, GitHub. Knowledge of Babel tools. Willingness for active professional growth. Excellent communicative skills in Polish and sufficient English for reading/writing technical documentation. It is a strong plus if you have: Knowledge of digital/programmatic advertising. Familiarity with React.js and NoSQL databases. Experience working in Unix environments, including writing bash scripts. Hands-on experience with Jenkins. Familiarity with Agile, Scrum, or KANBAN methodologies. Experience with Datadog. Knowledge of test frameworks like Jest, Jasmine, Karma, Cypress. Ability to write unit, functional, and integration tests. Language Required for the role: Communicative proficiency in Polish. English skills sufficient for technical documentation. Eligibility for the role: Only candidates with an existing legal right to work in the European Union will be considered for this role. #MAKEYourCareerBETTER Interested? Apply now and include your CV (preferably in English) along with a statement confirming your consent to the processing and storage of your personal data.

🏢 Summary: Backend Developer role focused on modernizing and transforming legacy sales systems using Node.js and .NET technologies. The position involves building and maintaining APIs, developing databases, and contributing to an event-driven architecture in an AWS-based environment. The role combines hands-on backend development with active participation in deployment processes and system evolution. 🗂️ Requirements: 5-6 years of recent Node.js development experience, 2-3 years of recent .NET development experience, Experience building and maintaining APIs, Experience with PostgreSQL and DynamoDB databases, Experience working with event-driven architecture, Experience with AWS services, Ability to write modern, testable, high-quality code, Experience with deployment automation and CI/CD pipelines 📃 Skills: Node.js, TypeScript, JavaScript, .NET, AWS, Lambda, DynamoDB, RDS, ECS, CDK, PostgreSQL, Kafka, EventBridge, GitLab, CI, Docker, Localstack 🏢 Description: We're seeking an experienced & energetic Backend Developer specializing in TypeScript/JavaScript/.NET to enhance the global Sales ecosystem. This role focuses on transforming backend systems, emphasizing proactive development and team empowerment. Candidates should bring a blend of Node.js and .NET expertise to the table, along with a collaborative spirit and a commitment to writing modern, testable code. Our Client’s team, comprising about 25 individuals, is modernizing legacy systems to fulfill local market needs while improving our processes continually. If you're motivated by challenges and have a passion for creating high-value solutions, we want to hear from you! What we offer: Rate: 40-45 euro/h +VAT Remote role B2B Contract Main Responsibilities: Drive initiatives and collaborate with team members on larger projects. Fix bugs and implement smaller enhancements across the application. Participate in creating and maintaining APIs using AWS services. Develop and improve databases with a focus on PostgreSQL and DynamoDB. Contribute to an event-driven architecture utilizing Kafka and AWS EventBridge. Manage deployment processes using AWS CDK and GitLab CI. Support legacy system maintenance and modernization. Key Requirements: At least 5-6 years of recent experience as a Node.js Developer. 2-3 years of recent experience with .NET. Energetic and inspiring personality who thrives on challenges. Hands-on work ethic in collaboration with team members. Proficiency in writing modern, testable, and high-quality code. Natural inclination towards evolutive maintenance. Nice to Have: AWS experience (Serverless Lambda, DynamoDB, RDS, ECS, AWS CDK). Knowledge of Localstack. Experience with Docker. Other Details: This position allows for team activities at least twice per year in Sweden, with a focus on modernizing our legacy systems into proactive, quality-focused solutions. Join a team of about 25 members dedicated to driving transformative change in our sales ecosystem.

🏢 Summary: Long-term remote B2B contract for a Senior Node.js Developer to extend and maintain a Commercial Data Manager (CDM) platform and take technical ownership of HubSpot backend. The role focuses on backend development, API design, microservices, and cloud-based infrastructure in close collaboration with architects. Project runs until August 2026 with possible extension. 🗂️ Requirements: 6+ years backend development experience, 4+ years Node.js experience, 3+ years TypeScript experience, Experience with REST APIs and GraphQL, Experience with microservices architecture, Experience with PostgreSQL, MySQL, MongoDB, Experience with AWS, Experience with Docker and Kubernetes, Experience with Prometheus, Grafana or ELK, Strong DevOps mindset, English level B2 or higher 📃 Skills: Node.js, TypeScript, REST, GraphQL, Microservices, PostgreSQL, MySQL, MongoDB, AWS, Docker, Kubernetes, Prometheus, Grafana, ELK, Kafka 🏢 Description: We are looking for Senior Node.js Developers to join a long-term remote project for a global digital transformation company. You will work on extending and maintaining an in-house Commercial Data Manager (CDM) platform and take technical ownership of HubSpot (built previously by an external agency).Work split: 70% CDM / 30% HubSpot , working closely with the architect. Location: Remote (EU / Poland) Contract: B2B Start: 02 Mar 2026 Duration: Until 31 Aug 2026 (extension likely) Language: English B2 Responsibilities Develop and extend backend services for the Commercial Data Manager (CDM) Take ownership of HubSpot backend maintenance and further development Design and implement REST / GraphQL APIs and microservices Work closely with architects and engineering teams Support team growth through technical leadership and knowledge sharing Ensure high code quality, scalability, and reliability Must-Have Skills 6+ years of backend development experience 4+ years with Node.js 3+ years with TypeScript Experience with REST APIs / GraphQL / microservices Databases: PostgreSQL, MySQL, MongoDB AWS , Docker , Kubernetes Monitoring/logging: Prometheus, Grafana, ELK Strong DevOps mindset English B2 Nice to Have Distributed systems Kafka or other message brokers What We’re Looking For Senior engineers who are proactive, confident in decision-making, willing to take ownership, and strong team players. 📩 Apply: marcillina.tietjen@dcvtechnologies.co.uk

🏢 Summary: Full-time Senior Back-End Engineer (Node.js) role focused on designing and maintaining scalable, high-performance server-side applications and APIs for modern, data-driven platforms. The position involves building RESTful services, integrating with third-party systems, ensuring code quality through testing, and optimizing system reliability and performance. Hybrid work model in Warsaw with B2B or CoE contract options. 🗂️ Requirements: Strong experience with Node.js, Strong experience with Express.js, Experience building and integrating APIs (GraphQL or REST), Knowledge of OAuth, JWT, and session-based authentication, Experience with MySQL, Experience with PostgreSQL, Experience writing unit tests with Chai and Mocha, Experience using Git and version control systems 📃 Skills: Node.js, Express.js, GraphQL, REST, OAuth, JWT, MySQL, PostgreSQL, Chai, Mocha, Git 🏢 Description: Senior Back-End Engineer (Node.js) 💰 Salary: 18,700-20,900 PLN/Month 💻 Warsaw, Poland (Hybrid - 3 days in office, 2 days remote) 🕦 Full-time ☑️ B2B or CoE We’re looking for a Senior Back-End Engineer to join a fast-growing international tech company focused on building modern, data-driven platforms that power digital transformation in the financial and enterprise sectors. Requirements: Strong experience in building server-side applications using Node.js and Express.js. Hands-on experience with API development and integration, particularly with GraphQL or RESTful services. Strong knowledge of authentication and authorization mechanisms (OAuth, JWT, session-based). Strong experience with databases such as MySQL and  PostgreSQL. Experience writing unit tests with tools such as Chai and Mocha. Strong experience using Git and version control systems. Proficiency in English (both written and spoken). Nice To have: Bachelor’s degree in Computer Science or a related field. Experience with cloud platforms (AWS, Azure, or GCP), as well as containerization and orchestration tools such as Docker and Kubernetes. Experience with microservices architecture. Experience setting up CI for static analysis and test execution. Experience developing RAG applications and storing data in vector embeddings. Key Responsibilities: Design, build, and maintain scalable, high-performance server-side applications and RESTful APIs using Node.js and Express.js. Guide and supervise the development of key code components to ensure long-term reliability and scalability. Integrate with front-end components and third-party services. Actively review the codebase, recommending and implementing refinements where needed. Write unit and integration tests and optimize performance to ensure high-quality code. Collaborate closely with cross-functional teams to define and implement technical solutions. Improve system performance, reliability, and long-term maintainability through optimization and best practices. Get to know DevsData: We are a technology consulting company and a recruitment agency, delivering software solutions to clients from Europe and the US. We work 100% remotely, in an international team, including people from Asia, London, or San Francisco. We employ people with experience in international corporations as well as students of the best technical and business universities. Find out more: https://devsdata.com/