Senior Backend Engineer (Payments focused)

🏢 Summary: Senior Backend Engineer role focused on building and scaling payment infrastructure across multiple SaaS products using Node.js and microservices. The position involves developing high-performance backend systems, integrating payment providers, and optimizing PostgreSQL databases in a distributed environment. The engineer will own payment lifecycle integrations and contribute to scalable, maintainable backend architecture. 🗂️ Requirements: 5+ years commercial experience with Node.js and RESTful APIs, 1+ year commercial experience with NestJS, 1+ year experience integrating and maintaining Stripe, 1+ year experience with payment orchestration platforms (Primer, Gr4vy, or Spreedly), Hands-on experience with full payment lifecycle (authorization, capture, refunds, webhooks, reconciliation), Experience with third-party API integrations, Strong understanding of microservices architecture, Advanced PostgreSQL experience with ORM, Experience with unit and integration testing, Experience with observability and monitoring tools, Experience with Docker and Kubernetes, Experience with AI development tools (e.g., Copilot, ChatGPT), Fluent English (written and spoken) 📃 Skills: Node.js, NestJS, Stripe, Primer, Gr4vy, Spreedly, REST, PostgreSQL, ORM, Jest, GroundCover, Docker, Kubernetes, Redis, AWS, React, Next.js, HTML, CSS, Adyen, Checkout, PayPal, CI/CD 🏢 Description: Senior Backend Engineer (Payments focused) Position Title: Senior Backend Engineer (Payments focused) Department: Business & Product Reports To: Technical Delivery Manager Location: Remote / Europe Date: ASAP Projects & Initiatives: Multi-project Node.js       NestJS       Stripe (Adyen, Checkout.com , PayPal) PostgreSQL       Microservices 1. Job Purpose We're a fast-growing tech company with a portfolio of SaaS products serving diverse industries. Innovation, performance, and design precision are core to our values. As we scale, we're looking for a Senior Back-End Engineer to take a key role in crafting highly performant, maintainable, and user-focused web applications, with a strong focus on payments infrastructure across multiple products. 2. Key Responsibilities – Participate in daily team routines, stand-ups, sprint planning, and retrospectives. – Actively contribute to sprint work: feature development, code reviews, and merge requests. – Develop testable, maintainable code; troubleshoot and debug issues as they arise. – Gather and evaluate requirements in collaboration with the Tech Lead, Product Manager, and fellow engineers. – Translate requirements into solid backend features – Integrate software components into a fully functional system – Collaborate effectively with Product, Engineering, QA, and Customer Support – Integrate with third-party APIs and monitor system performance – Apply engineering best practices and agreed standards consistently – Prepare and present technical ideas to internal teams and stakeholders 3. Requirements MUST HAVE – 5+ years of commercial experience with Node.js and RESTful APIs – 1+ year of commercial experience with NestJS – 1+ year integrating and maintaining Stripe – 1+ year integrating and maintaining a payment orchestration platform, Primer, Gr4vy, or Spreedly – Proficient in English, written and spoken ALSO REQUIRED – Hands-on experience with the full payment lifecycle: ◦ Authorization, capture, refunds, webhooks, reconciliation ◦ Third-party API integrations – Thorough understanding of web application and microservice architecture – Comprehensive understanding of OOP, design patterns, and service-oriented architecture – Advanced PostgreSQL experience with ORM: ◦ Designing scalable schemas ◦ Performance optimization ◦ Schema and data migrations under heavy load – Experience with unit and integration tests, e.g., Jest – Experience with observability and monitoring in distributed environments, e.g., GroundCover – Knowledge of application performance optimization techniques – Understanding of web technologies – Comfortable with Docker and Kubernetes – Hands-on with modern AI development tools, e.g., GitHub Copilot, Cursor, ChatGPT, or similar – Strategic thinker with a problem-solver mindset – Able to work autonomously in a fast-paced, agile, remote environment – Strong communication skills and experience working with distributed teams 4. Nice to Have – Experience with other payment processors, Adyen, Checkout.com , and PayPal – Understanding of payment performance processes, EFWs, chargebacks, and refunds – Experience with Redis – Familiarity with CI/CD tools and practices – Experience with AWS – React.js / Next.js – HTML / CSS – Experience with SaaS products – Past or current Tech Lead experience 5. What We Offer – Full-time, long-term role – 22 days paid leave + local bank holidays – 100% remote – Flexible hours, core window 7:00–18:00 EET – High-traffic, global SaaS products, real scale, real impact

🏢 Summary: Senior Fullstack Engineer role focused on building modern, scalable web applications using React and Node.js, with strong emphasis on frontend development. The position covers the full application stack, including backend services, API design, and data management. You will collaborate with cross-functional teams to deliver high-quality, accessible, and high-performance digital products. 🗂️ Requirements: Strong commercial experience with React, Strong commercial experience with Node.js, Experience with React Router, Experience with TanStack Query, Experience integrating Headless CMS (preferably Contentful), Understanding of API design principles, Experience with PostgreSQL, Experience with Redis, Experience with Vitest, Experience with Playwright, Knowledge of WCAG accessibility standards, Experience with performance optimisation, Ability to work across full software development lifecycle 📃 Skills: React, Node.js, TypeScript, Fastify, PostgreSQL, Redis, React Router, TanStack Query, Contentful, Vitest, Playwright, WCAG, SAP Gigya, Salesforce 🏢 Description: Senior Fullstack Engineer (React & Node.js) About the Role We are looking for a Senior Fullstack Engineer to join a product team building modern, scalable web applications and digital experiences. You will work across the entire application stack, from user-facing interfaces to backend services and integrations. The role has a strong focus on frontend engineering while also involving backend development, API design, and data management. You will collaborate closely with product, design, and engineering teams to deliver high-quality, accessible, and performant applications. Responsibilities Develop and maintain modern web applications using React, Node.js, and TypeScript. Build scalable and reusable UI components integrated with a design system. Develop and maintain backend services and APIs using Node.js and Fastify. Integrate applications with CMS platforms and third-party services. Work with PostgreSQL and Redis to support application functionality and performance. Write and maintain automated tests, including unit and end-to-end tests. Ensure high standards of accessibility, performance, and code quality. Participate in architectural discussions and contribute to engineering best practices. Requirements Strong commercial experience in fullstack development using React and Node.js. Solid experience with modern frontend technologies, including React Router and TanStack Query. Experience integrating with Headless CMS platforms, preferably Contentful. Good understanding of API design and backend development principles. Experience with PostgreSQL and Redis. Experience with automated testing frameworks such as Vitest and Playwright. Strong understanding of accessibility standards (WCAG) and performance optimisation. Ability to work across the entire software development lifecycle in a product-oriented environment. Nice to Have Experience with authentication and identity platforms such as SAP Gigya. Experience integrating Salesforce products or loyalty platforms. Experience in highly scalable, customer-facing digital products. Experience working in agile, cross-functional product teams.

🏢 Summary: Senior Backend Engineer role focused on defining the technical direction and architecture of a domain within a borderless financial platform. The position involves designing scalable microservices, driving architectural decisions, and leading a small backend team in a distributed environment. The role emphasizes reliability, security, and high‑volume transaction processing in a cloud-based ecosystem. 🗂️ Requirements: 4-7 years backend engineering experience, Proficiency in Go, Experience with Java 21 or modern Java, Experience designing microservices with clear contracts, Experience with caching strategies including TTL and invalidation, Experience with event-driven or asynchronous architectures, Experience with structured logging, metrics, and alerting, Experience with AWS services, Experience with relational and non-relational databases, Experience with Spring Boot or similar frameworks, Experience reviewing code and architectural decisions, Availability to work in GMT+5:30 timezone 📃 Skills: Java, Go, Spring, JDBI, PostgreSQL, CockroachDB, DynamoDB, Redis, SQS, SNS, Kafka, AWS, EKS, ALB, RDS, S3, Kong, Datadog, Quickwit, JWT, RBAC, TLS, Docker, ArgoCD, GitHub, Microservices, Kafka, CDC 🏢 Description: Project overview This project focuses on developing a borderless financial platform that supports international banking flows, payments, account management and regulatory compliant operations. The product handles sensitive data and high volume transactions while prioritising reliability and security. Team You will work in a distributed environment with backend engineers, a product manager and platform specialists. The role involves leading a sub team of three to five engineers, conducting design reviews, ensuring code quality standards and supporting collaborative decision making. Position overview We are looking for a Senior Backend Engineer who will define the technical direction of a backend domain and drive architectural decisions. You will design microservices, create scalable solutions, guide a small engineering group and collaborate closely with product specialists to shape the delivery roadmap. We are looking for a person willing to work in the time zone: GMT+5:30. Technology stack Java 21, Go, Spring Boot, JDBI, custom workflow engines, PostgreSQL, CockroachDB, DynamoDB, Redis, SQS, SNS, Kafka, AWS EKS ALB RDS S3 Secrets Manager, Kong API Gateway, Datadog, Quickwit, JWT RBAC TLS request and response encryption VAPT, GitHub Actions, Docker, ArgoCD, microservices, event driven architecture, saga and orchestration patterns, CDC pipelines, maker checker workflows Responsibilities Plan and design backend microservices with clear boundaries and contracts Develop solutions for domains such as onboarding, payments, transaction orchestration or platform components Break complex epics into actionable tasks with clear acceptance criteria Review designs from other engineers to ensure scalability and fault tolerance Drive technical decisions including caching layers, asynchronous processing strategies, database choices and API versioning Evaluate build versus buy options for integrations and services Collaborate with a product manager to align on scope and prioritisation Lead a sub team of backend engineers and support their professional growth Support incident response, root cause analysis and long term improvements Monitor service performance using logging, metrics and tracing tools Requirements Professional backend engineering experience from 4-7 years Experience with Go (tooling & CLIs) Experience designing microservices with well-defined contracts and boundaries Experience with Java 21 or modern Java versions Experience with caching strategy design, including TTL and invalidation approaches Experience working with asynchronous processing, event-driven architecture, or queue-based workflows Experience using structured logging, metrics, and alerting to debug production systems Experience in making build versus buy decisions with clear trade-off analysis Experience reviewing code and identifying architectural or contract issues Experience with AWS-based services Experience working with relational and non-relational databases such as PostgreSQL or DynamoDB Experience writing backend services using Spring Boot or similar frameworks Nice to have Experience with financial or payments related systems Experience with KYC or AML flows Experience with workflow or orchestration engines Experience with platform wide pattern creation or reusable service design Experience with data encryption practices and security audits Experience with CockroachDB or high availability distributed databases What We Offer: Vacation days : Up to 26 business days per year. 10 illness/special days off per year (fully paid, no medical papers needed) for all contract types Health and life insurance (Luxmed) MyBenefit platform with Multisport option Internal psychological support service English language classes from the first working day Access to external learning platforms : O’Reilly, LinkedIn Learning, Udemy, and a wide catalog of diverse internal training Flexible workplace : work from the office, from home, or choose a hybrid option Tech Skills Mentoring Program Opportunities to develop as a public speaker, mentor, or technical interviewer Fully paid idle (bench) when not involved in a project Certification reimbursement (AWS, GCP, Microsoft, etc.)

🏢 Summary: Mid to senior backend engineer role focused on designing and scaling enterprise-grade backend services and integrations using Node.js and cloud-native technologies. The position involves building high-performance APIs, optimizing databases, leading CI/CD and DevOps practices, and mentoring engineering teams in complex enterprise environments. Fully remote opportunity available as full-time or B2B. 🗂️ Requirements: Minimum 5+ years of backend development experience with Node.js, TypeScript, NestJS, Proven experience designing and scaling RESTful APIs and SOAP services, Advanced PostgreSQL administration including performance tuning, replication, partitioning, Strong experience with Git workflows and CI/CD pipelines, Hands-on experience with AWS services (EC2, EKS, Lambda, S3, RDS, CloudWatch, API Gateway), Solid knowledge of Kubernetes deployment and scaling, Experience with monitoring and observability tools, Experience with infrastructure as code tools, Bachelor’s degree in Computer Science, Software Engineering, or related field 📃 Skills: Node.js, TypeScript, NestJS, PostgreSQL, Citus, Patroni, TimescaleDB, REST, SOAP, Swagger, OpenAPI, Postman, Git, GitHub, GitLab, GitHubActions, Jenkins, SonarQube, ESLint, Prettier, AWS, EC2, EKS, Lambda, Fargate, S3, RDS, CloudWatch, APIGateway, Docker, Kubernetes, Helm, Splunk, Prometheus, Grafana, Spinnaker, ArgoCD, AzureDevOps, Terraform, CDK 🏢 Description: We are seeking a mid to senior level engineer with deep expertise in backend engineering, cloud-native architecture, and enterprise system integration. Key Responsibilities Design, develop, and maintain enterprise-grade backend services using Node.js, TypeScript, and NestJS . Architect and implement high-performance REST and SOAP APIs for complex enterprise integrations. Optimize PostgreSQL databases for high availability, partitioning, replication, and performance tuning. Define and enforce secure coding practices, design patterns, and architectural principles . Collaborate with DevOps, frontend, QA, and product stakeholders to ensure seamless integration and delivery. Troubleshoot production issues, enhance reliability, and implement performance tuning at scale. Lead code reviews, enforce coding standards , and integrate quality gates in CI/CD pipelines. Mentor client engineering teams, contribute to technical strategy and architecture decisions . Integrate external systems, tools, and services to extend backend capabilities. Provide continuous innovation by adopting cloud-native, serverless, and emerging backend technologies . Required Qualifications Minimum 5+ years of backend development experience with Node.js, TypeScript, and NestJS. Proven expertise in designing and scaling RESTful APIs and SOAP services for enterprise-grade systems. Advanced proficiency in PostgreSQL administration (performance tuning, replication, partitioning). Strong experience with Git workflows, CI/CD pipelines, and automated quality controls . Deep understanding of cloud-native architectures and serverless implementations . Hands-on experience with AWS services (EC2, EKS, Lambda, S3, RDS, CloudWatch, API Gateway). Solid knowledge of Kubernetes (deployment, scaling, troubleshooting). Experience mentoring teams and driving technical leadership in multi-stakeholder environments . Expertise with Splunk (monitoring, dashboards, alerting). Familiarity with Spinnaker or advanced deployment pipelines . Education Bachelor’s degree in Computer Science, Software Engineering, or related field (required). Master’s degree preferred but not mandatory. Technology / Systems Expertise Node.js + NestJS + TypeScript – backend framework. PostgreSQL with advanced extensions (Citus, Patroni, TimescaleDB). Swagger / OpenAPI + Postman – API documentation & testing. GitHub / GitLab + GitHub Actions / Jenkins – version control & CI/CD automation. SonarQube, ESLint, Prettier – code quality enforcement. AWS (EC2, EKS, Lambda, Fargate, S3, RDS, CloudWatch, API Gateway) – cloud & serverless stack. Docker + Kubernetes (EKS) + Helm – containerization & orchestration. Splunk, Prometheus, Grafana – monitoring & observability. Spinnaker / ArgoCD/ Azure Devops – automated deployment pipelines. Terraform / AWS CDK – infrastructure as code. Skills & Capabilities Demonstrated expertise in backend architecture and scalable API design . Advanced database optimization & high availability strategies . Strong proficiency in CI/CD, GitOps, and DevOps integration . Hands-on experience in cloud-native and Kubernetes-based deployments . Proven ability to mentor engineers, lead architecture decisions, and drive best practices . All our positions are Remote and are available as Full Time Employment or B2B Contracts.

🏢 Summary: Senior Full-stack Engineer role focused on building and scaling a modern B2B SaaS platform for subscription-based e-commerce. The position involves end-to-end feature delivery, architectural decisions, and improving system scalability and reliability. High-impact role with strong ownership over technical direction and product evolution. 🗂️ Requirements: 7+ years engineering experience in complex systems, Strong system design skills, Experience designing scalable architectures, Full-stack development experience, Experience building SaaS platforms, Experience with e-commerce systems 📃 Skills: JavaScript, TypeScript, SaaS, Architecture, Scalability, Reliability, APIs, Ecommerce, Payments, Cloud 🏢 Description: Senior Full-stack Engineer Our client is building a modern B2B SaaS platform that enables businesses to launch and scale subscription-based models for physical and digital products. The product sits at the intersection of e-commerce, payments, and developer tooling, with a strong focus on extensibility and developer experience. The team is lean, senior, and highly experienced, backed by strong investors and industry advisors. They operate with high autonomy, fast execution, and strong ownership culture. Role We are looking for a Senior Full-stack Engineer to help shape the next evolution of the platform. You will work across architecture, product, and infrastructure, focusing on scalability, reliability, and developer experience. This is a high-impact role where you will influence both technical direction and product decisions. Responsibilities Build and evolve a scalable SaaS platform Design and deliver new features end-to-end Improve performance, reliability, and system architecture Collaborate with product, design, and growth teams Requirements 7+ years of engineering experience in complex systems Strong architectural and system design skills Ability to choose appropriate technologies per problem Experience working in cross-functional teams Strong communication in Polish and English Startup mindset: ownership, speed, adaptability Experience with e-commerce platforms is a plus Offer High-impact role in a senior engineering team with real product ownership and influence. Competitive salary plus ESOP, fully remote work (Poland), regular team offsites, and modern tooling including MacBook Pro and AI credits. Direct access to founders, investors, and advisors.

🏢 Summary: Senior FullStack Developer role in a fast-growing SaaS environment, responsible for designing and delivering scalable, high-performance web applications using NestJS and NextJS. The position involves leading architectural decisions, ensuring code quality, optimizing system performance, and mentoring engineers across cross-functional squads. You will drive backend and frontend development, CI/CD reliability, and production stability in a modern, zero-legacy stack. 🗂️ Requirements: 5+ years of fullstack development experience, Strong experience with NestJS, Node.js, NextJS, and TypeScript, Strong knowledge of PostgreSQL, data modeling, and optimization, Experience building and consuming REST APIs with JWT authentication, Ability to lead architecture decisions and enforce code quality, Experience with CI/CD pipelines and Docker, Frontend performance optimization experience (SSR, lazy loading, state management), Ability to collaborate in cross-functional teams (product, QA, design) 📃 Skills: NestJS, Node.js, NextJS, TypeScript, PostgreSQL, REST, JWT, CI/CD, Docker, Kubernetes, ArgoCD, Storybook, React, Kafka, RabbitMQ, AWS, Terraform, Sentry, Datadog, Groundcover 🏢 Description: Job Purpose We are a fast-growing tech company with a portfolio of SaaS products serving diverse industries. Innovation, performance, and design precision are core to our values. As we scale, we are looking for a talented Senior FullStack Developer to join our team and take a key role in crafting highly performant, maintainable, and user-focused web applications. Key Responsibilities - Contribute to both backend (NestJS) and frontend (NextJS) systems by designing and building scalable, secure, and maintainable features, while leading architecture decisions across services, APIs, and cross-stack boundaries - Champion clean code, modular design, and testability through active contribution, reusable components, and mentoring - Drive system-level decisions around performance, observability, and scalability, and ensure alignment between product goals and technical implementation - Own and enforce code quality via reviews, maintain CI/CD reliability, and collaborate closely with DevOps to ensure release stability and consistent environments - Monitor and optimize system performance, define logging and alerting standards, and lead incident response and continuous improvement efforts - Work closely with product, QA, and designers to unblock delivery, while mentoring engineers and fostering technical alignment across squads Required Skills & Qualifications - 5+ years of fullstack development experience - Strong experience with NestJS, Node.js, NextJS, and TypeScript - Strong understanding of PostgreSQL, data modeling, and optimization techniques - Solid experience building and consuming REST APIs with secure JWT-based authentication flows - Proven ability to lead architecture decisions, enforce code quality, and guide teams through technical complexity - Familiarity with CI/CD pipelines, Docker, and environment management (K8s, ArgoCD are a plus) - Experience with frontend performance optimization (SSR, lazy loading, state management) - Comfortable working in cross-functional squads with product, QA, and design - Good communication skills Nice to Have - Experience with component libraries (e.g., Storybook, React UI) or design systems - Exposure to event-driven systems using tools like Kafka, RabbitMQ, or AWS SNS/SQS - Knowledge of Infrastructure as Code (Terraform) - Background in observability tooling (e.g., Sentry, Datadog, Groundcover) and defining alerting/logging standards - Contributions to internal platforms, shared packages, or developer experience tools Soft Skills - Clear written and async communication, especially in distributed teams - Systemic thinking — sees the bigger picture across stack, squads, and product - Ownership mindset, from design to delivery to incident resolution - Pragmatic decision-making, balancing trade-offs in real-world scenarios Key Performance Indicators (KPIs) - End-to-end feature delivery reliability - Architecture quality and system scalability - Code review throughput and mentorship impact - Production stability and issue resolution time - Documentation, testing, and developer experience What We Offer - Competitive compensation - 22 paid vacation days + local national holidays - Annual learning & development budget - Opportunity to impact a fast-growing multi-product company - Cross-functional projects, modern stack, and zero legacy burden

🏢 Summary: Senior FullStack Developer role focused on building and scaling high-performance web applications using NestJS and NextJS. The position involves leading architecture decisions, ensuring code quality, and optimizing performance across backend and frontend systems. You will drive scalable, secure solutions and maintain reliable CI/CD and production environments. 🗂️ Requirements: 5+ years of fullstack development experience, Strong experience with NestJS, Node.js, NextJS, TypeScript, Strong knowledge of PostgreSQL and data modeling, Experience building and consuming REST APIs, Experience implementing JWT-based authentication, Ability to design scalable and secure architectures, Experience with CI/CD pipelines and Docker, Experience optimizing frontend performance (SSR, lazy loading, state management), Ability to enforce code quality and conduct code reviews 📃 Skills: NestJS, Node.js, NextJS, TypeScript, PostgreSQL, REST, JWT, Docker, CI/CD, Kubernetes, ArgoCD, Kafka, RabbitMQ, AWS, SNS, SQS, Terraform, Sentry, Datadog, Groundcover, Storybook, React 🏢 Description: 1. Job Purpose We are a fast-growing tech company with a portfolio of SaaS products serving diverse industries. Innovation, performance, and design precision are core to our values. As we scale, we are looking for a talented Senior FullStack Developer to join our team and take a key role in crafting highly performant, maintainable, and user-focused web applications. 2. Key Responsibilities Contribute to both backend (NestJS) and frontend (NextJS) systems by designing and building scalable, secure, and maintainable features, while leading architecture decisions across services, APIs, and cross-stack boundaries. Champion clean code, modular design, and testability through active contribution, reusable components, and mentoring. Drive system-level decisions around performance, observability, and scalability, and ensure alignment between product goals and technical implementation. Own and enforce code quality via reviews, maintain CI/CD reliability, and collaborate closely with DevOps to ensure release stability and consistent environments. Monitor and optimize system performance, define logging and alerting standards, and lead incident response and continuous improvement efforts. Work closely with product, QA, and designers to unblock delivery, while mentoring engineers and fostering technical alignment across squads. 3. Required Skills & Qualifications Experience: 5+ years of fullstack development experience; NestJS , Node.js , NextJS , and TypeScript Strong understanding of PostgreSQL , data modeling, and optimization techniques Solid experience building and consuming REST with secure JWT-based auth flows Proven ability to lead architecture decisions, enforce code quality, and guide teams through technical complexity Familiarity with CI/CD pipelines , Docker , and environment management (bonus: K8s, ArgoCD) Experience with frontend performance optimization (SSR, lazy loading, state management) Comfortable working in cross-functional squads with product, QA, and design Good communication skills Nice to Have: Experience with component libraries (e.g., Storybook, React UI) or design systems Exposure to event-driven systems using tools like Kafka, RabbitMQ, or AWS SNS/SQS Knowledge of Infrastructure as Code (Terraform) Background in observability tooling (e.g., Sentry, Datadog, Groundcover) and defining alerting/logging standards Contributions to internal platforms, shared packages , or developer experience tools Soft Skills Clear written and async communication, especially in distributed teams Systemic thinking — sees the bigger picture across stack, squads, and product Ownership mindset, from design to delivery to incident resolution Pragmatic decision-making, balancing trade-offs in real-world scenarios 4. Key Performance Indicators (KPIs) End-to-end feature delivery reliability Architecture quality and system scalability Code review throughput and mentorship impact Production stability and issue resolution time Documentation, testing, and developer experience 5. What We Offer Competitive compensation 22 paid vacation days + local national holidays Annual learning & development budget Opportunity to impact a fast-growing multi-product company Cross-functional projects, modern stack, and zero legacy burden

🏢 Summary: Senior FullStack Developer role focused on building and scaling high-performance SaaS web applications using NestJS and NextJS. The position involves leading architecture decisions, ensuring code quality, and optimizing system performance across backend and frontend. The role also drives CI/CD reliability, observability standards, and cross-functional technical alignment. 🗂️ Requirements: 5+ years fullstack development experience, Strong experience with NestJS, Node.js, NextJS, TypeScript, Strong knowledge of PostgreSQL and data modeling, Experience building and consuming REST APIs, Implementation of JWT-based authentication, Experience with CI/CD pipelines, Experience with Docker and environment management, Frontend performance optimization (SSR, lazy loading, state management), Ability to lead architecture decisions and enforce code quality 📃 Skills: NestJS, Node.js, NextJS, TypeScript, PostgreSQL, REST, JWT, CI/CD, Docker, Kubernetes, ArgoCD, Kafka, RabbitMQ, AWS, Terraform, Sentry, Datadog, Groundcover, Storybook, React 🏢 Description: 1. Job Purpose We are a fast-growing tech company with a portfolio of SaaS products serving diverse industries. Innovation, performance, and design precision are core to our values. As we scale, we are looking for a talented Senior FullStack Developer to join our team and take a key role in crafting highly performant, maintainable, and user-focused web applications. 2. Key Responsibilities Contribute to both backend (NestJS) and frontend (NextJS) systems by designing and building scalable, secure, and maintainable features, while leading architecture decisions across services, APIs, and cross-stack boundaries. Champion clean code, modular design, and testability through active contribution, reusable components, and mentoring. Drive system-level decisions around performance, observability, and scalability, and ensure alignment between product goals and technical implementation. Own and enforce code quality via reviews, maintain CI/CD reliability, and collaborate closely with DevOps to ensure release stability and consistent environments. Monitor and optimize system performance, define logging and alerting standards, and lead incident response and continuous improvement efforts. Work closely with product, QA, and designers to unblock delivery, while mentoring engineers and fostering technical alignment across squads. 3. Required Skills & Qualifications Experience: 5+ years of fullstack development experience; NestJS , Node.js , NextJS , and TypeScript Strong understanding of PostgreSQL , data modeling, and optimization techniques Solid experience building and consuming REST with secure JWT-based auth flows Proven ability to lead architecture decisions, enforce code quality, and guide teams through technical complexity Familiarity with CI/CD pipelines , Docker , and environment management (bonus: K8s, ArgoCD) Experience with frontend performance optimization (SSR, lazy loading, state management) Comfortable working in cross-functional squads with product, QA, and design Good communication skills Nice to Have: Experience with component libraries (e.g., Storybook, React UI) or design systems Exposure to event-driven systems using tools like Kafka, RabbitMQ, or AWS SNS/SQS Knowledge of Infrastructure as Code (Terraform) Background in observability tooling (e.g., Sentry, Datadog, Groundcover) and defining alerting/logging standards Contributions to internal platforms, shared packages , or developer experience tools Soft Skills Clear written and async communication, especially in distributed teams Systemic thinking — sees the bigger picture across stack, squads, and product Ownership mindset, from design to delivery to incident resolution Pragmatic decision-making, balancing trade-offs in real-world scenarios 4. Key Performance Indicators (KPIs) End-to-end feature delivery reliability Architecture quality and system scalability Code review throughput and mentorship impact Production stability and issue resolution time Documentation, testing, and developer experience 5. What We Offer Competitive compensation 22 paid vacation days + local national holidays Annual learning & development budget Opportunity to impact a fast-growing multi-product company Cross-functional projects, modern stack, and zero legacy burden

🏢 Summary: Senior Fullstack Software Engineer role focused on building scalable, cloud-native applications with a strong backend emphasis (70% backend, 30% frontend). The position involves designing distributed, event-driven systems on AWS, developing REST APIs, and contributing across the full stack using Node.js, TypeScript, React, and Next.js. The engineer will drive architectural decisions, scalability, and technical direction while collaborating with cross-functional teams in a US-aligned remote environment. 🗂️ Requirements: Strong experience as Senior Software Engineer in product-focused environments, Advanced backend development with Node.js and TypeScript, Experience building and consuming REST APIs, Frontend development experience with React and TypeScript, Experience with AWS or other cloud platforms, Strong knowledge of distributed and scalable system design, Experience with MySQL and PostgreSQL databases, Experience with event-driven architectures, Experience with queuing or messaging systems, Ability to write clean, maintainable, scalable code, Strong debugging and problem-solving skills, Availability to work overlapping US hours 📃 Skills: Node.js, TypeScript, React, Next.js, AWS, REST, MySQL, PostgreSQL, SQL, APIs, Microservices, Event-driven, Messaging, Queues, Cloud, Distributed-systems 🏢 Description: Fullstack Senior Software Engineer Location: Remote We are looking for a talented Senior Fullstack Software Engineer to join a high-performing product engineering team focused on building scalable, modern cloud-native applications. This role is best suited to an experienced engineer who is stronger on the backend (approximately 70% backend / 30% frontend) and enjoys designing robust distributed systems while still being comfortable contributing across the full stack. You will play a key role in shaping technical direction, building scalable event-driven platforms, and contributing to product thinking - not just delivering code. We are looking for someone with strong ownership, accountability, and the ability to think about the wider business and customer impact of the solutions they build. This position requires alignment with US-based teams, and so the working hours must overlap. What You'll Be Doing Designing, building, and maintaining scalable backend services using Node.js and TypeScript Developing and supporting modern frontend applications using React and Next.js Building robust RESTful APIs and backend integrations Contributing to distributed, cloud-native systems running on AWS Designing and implementing event-driven architectures and queue-based systems Working with SQL databases including MySQL and PostgreSQL Driving engineering best practices, scalability, reliability, and performance improvements Collaborating closely with Product, Engineering, and stakeholders to shape technical solutions Taking ownership of features and systems throughout the full software lifecycle Mentoring engineers and contributing to technical discussions and architectural decisions Required Skills & Experience Strong experience as a Software Engineer / Senior Software Engineer in modern product-focused environments Excellent backend development experience with: Node.js TypeScript REST APIs React TypeScript Experience building applications in AWS cloud environments (or other cloud platforms) Strong understanding of scalable and distributed system design MySQL PostgreSQL Proven experience building event-driven architectures and working with queuing/messaging systems (highly important) Ability to write clean, maintainable, and scalable code Strong problem-solving and debugging skills What We're Looking For Strong product mindset - someone who thinks beyond just delivering tickets and understands the "why" behind engineering decisions Ownership and accountability for technical delivery and outcomes Ability to contribute to architectural direction and scalability initiatives Comfortable working in fast-paced, collaborative engineering environments Passion for building high-quality, scalable software products Strong communication and stakeholder collaboration skills

🏢 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/