Full Stack Engineer (React/Node/C#) - Contractor

Full Stack Engineer (React/Node/C#)

Remote | Poland | B2B Contract

Direct applications only. We are seeking applications from individual contractors who will personally provide the services. No recruitment agencies, consultancies or third-party suppliers, please

CRU is looking for an experienced Full Stack Engineer Contractor to support the delivery of a business-critical commodity intelligence platform.

Help evolve a business-critical, data-heavy platform into an AI-augmented product used by analysts, traders and strategists across global commodity markets. You’ll own features from database query through application development and deployment on Azure, working across a modern TypeScript stack and a complex, data-rich business domain.

Key Responsibilities:

• Deliver full-stack features from SQL queries and NestJS GraphQL services to Apollo hooks and React components in Next.js.
• Partner with Data Engineering, which owns the schemas and data model, to build reliable product features.
• Deploy and support features on Azure App Services and Azure Functions using GitHub Actions; extend Terraform infrastructure as needed.
• Explore the database and user interface to understand assets, commodities, cost stages, emissions scopes and valuations, translating requirements into clear, testable features.
• Use AI tooling in the engineering workflow, help improve team practices, and critically validate AI-generated work.
• Build with testing, security, permissions and performance in mind, and contribute to enterprise readiness.
• Help manage delivery risks, issues and dependencies, and communicate technical details to non-technical stakeholders.

Skills & Experience:

• Strong written communication and the ability to contribute effectively in an async-first, distributed team.
• Proactive end-to-end ownership, with accountability for how features behave in production and in front of users.
• Curiosity about business domains and a willingness to explore data and the product to clarify requirements.
• Strong communication skills, including the ability to explain complex technical details to non-technical stakeholders.
• Experience helping manage delivery risks, issues and dependencies.
• A quality mindset, with testing, security and performance considered part of completing a feature.
• Daily use of AI tools, with the judgement to set team context and rules and critically validate generated outputs.

Technical Skills:

Must-have:

• TypeScript, including strong strict-typing practices.
• Node.js and NestJS, including services, modules, dependency injection and code-first GraphQL.
• GraphQL resolvers, pagination, error handling and awareness of N+1 query issues.
• SQL, including joins, aggregations, window functions and reading query plans.
• React 18 and Next.js 16 (App Router), including feature delivery, Apollo cache debugging and front-end pull-request review.
• Azure App Services and Azure Functions, including configuration, deployment slots, triggers, bindings, logs and troubleshooting deployed environments.
• GitHub Actions, including reading, debugging and extending build, test and deployment workflows, environments and secrets.
• Terraform, including navigating existing modules, proposing changes through pull requests and confidently reviewing plans.
• Vitest; write unit tests by default and understand the trade-offs between unit, integration and end-to-end testing.
• Daily use of at least one modern AI coding tool, such as Cursor or Claude Code.

Nice to have:

• Commercial C#/.NET experience with ASP.NET Core Web APIs and Entity Framework.
• ClickHouse experience, including the MergeTree family, materialised views, argMax, groupArray, projections, skipping indexes and query introspection.
• Experience writing efficient queries and reasoning about performance on large datasets.