Senior Frontend Engineer (React)

Get to know us betterCodiLime is a software and network engineering industry expert and the first-choice service partner for top global networking hardware providers, software providers and telecoms. We create proofs-of-concept, help our clients build new products, nurture existing ones and provide services in production environments. Our clients include both tech startups and big players in various industries and geographic locations (US, Japan, Israel, Europe).While no longer a startup - we have 250+ people on board and have been operating since 2011 we’ve kept our people-oriented culture. Our values are simple:Act to deliver.Disrupt to grow.Team up to win.The project and the teamYou will join the team behind a leading network source-of-truth (NSoT) platform, used by thousands of organizations - from fast-growing tech companies to Fortune 500 enterprises - to model, document, and automate their network infrastructure.CodiLime engineers work within the platform's Observability team, which connects the network source of truth with what is actually running on the network. The team builds products for network discovery, network assurance (detecting drift between the intended and the actual state of the network), management of the agents that collect discovery and telemetry data, and a reliable pipeline that ingests this data into the platform.The platform is built AI-first, with its own Claude Code agent skills and MCP server, and that mindset carries over to how the team works: Claude Code is used heavily day to day to help the team move fast and consistently deliver high-quality results.In this role, you will build the real-time monitoring and telemetry dashboards at the heart of the observability products - interfaces that help network operators make sense of large, constantly changing network data. The scale is significant: some of the platform's largest customers manage hundreds of thousands of devices across globally distributed environments.As the observability offering keeps growing, the team is looking for a Senior Frontend Engineer who enjoys React, thinks in terms of data visualization and works AI-first.Technology stack:Programming languages/Frontend: TypeScript, JavaScript, ReactBuild tooling: Vite, npmState management & data fetching: Zustand, TanStack Query, Context APIStyling: TailwindCSSTesting: Jest, React Testing Library (unit tests), Playwright (E2E)APIs: REST with OpenAPI contracts, gRPCData visualization: charting libraries for real-time telemetry dashboards (e.g. Recharts, D3)CI/CD: GitHub ActionsAI tooling: Claude Code, MCP servers, Anthropic toolingSecurity: OAuth2 / OIDCObservability: OpenTelemetry, metrics and instrumentation, Grafana, PrometheusContainerization & Orchestration: Docker (Docker Compose for local/test environments), KubernetesCloud: AWSWhat else you should know:Small, cross-functional team with strong ownership of code quality, security and testsThe team is distributed across Europe and the US, and we are looking for someone whose working hours can overlap with the US East CoastAI tools are part of the daily workflow - Claude Code is used heavily across the teamThis is a frontend-focused role, working closely with backend engineers on API contractsStartup-like vibe: proactive, ownership-driven, fast-pacedWe work on multiple interesting projects at a time, so it may happen that we’ll invite you to an interview for another project if we see that your competencies and profile are well suited for it.Your roleAs a part of the project team, you will be responsible for:Building real-time monitoring and telemetry dashboards for the platform's observability productsDesigning and developing React and TypeScript interfaces for network discovery, network assurance and agent fleet managementTurning large, frequently changing network and telemetry data into clear and usable visualizationsDefining and consuming frontend-backend contracts (OpenAPI) together with backend engineersManaging client state and server data efficiently (Zustand, TanStack Query, Context API)Writing unit tests (Jest, React Testing Library) and E2E tests (Playwright) running in CI (GitHub Actions)Making sure the product is accessible to all usersUsing Claude Code day to day: setting constraints, reviewing the output and staying accountable for correctness, security and testsWriting clean, maintainable, well-tested code and participating in code reviewsDo we have a match?As a Senior Frontend Engineer, you must meet the following criteria:7+ years of professional frontend development experienceStrong experience with React, TypeScript and JavaScriptExperience with ViteExperience with Zustand (or another state management library) and the Context APIExperience with TanStack QueryExperience with TailwindCSSGood understanding of frontend-backend contracts, ideally defined with OpenAPIExperience with unit testing (Jest, React Testing Library)Experience with E2E testing, ideally with PlaywrightExperience with npmCI/CD experience (ideally GitHub Actions)Experience with PostgreSQLExperience with Docker and Docker Compose (local and test environments)Understanding of accessibility, ideally hands-on experienceHands-on, everyday use of AI coding tools (ideally Claude Code)Experience building SaaS and infrastructure productsNetworking knowledge gained from working on observability or monitoring productsWorking hours overlapping with the US East CoastGood knowledge of English (minimum C1 level)Beyond the criteria above, we would appreciate the following nice-to-haves:Experience with data visualization libraries such as Recharts or D3Experience with observability tools such as GrafanaExperience with OAuth2 / OIDC (e.g. Auth0)Experience with RBAC (role-based access control) More reasons to join usFlexible working hours and approach to work: fully remotely, in the office or hybridProfessional growth supported by internal training sessions and a training budgetSolid onboarding with a hands-on approach to give you an easy startA great atmosphere among professionals who are passionate about their workThe ability to change the project you work on