Web Infrastructure Engineer

Attio is on a mission to redefine CRM for the AI era.

We’re building the first AI-native CRM — designed for the most ambitious go-to-market teams. We recently announced our $52M Series B, led by GV (Google Ventures), with support from Redpoint, Balderton, Point Nine, and 01A. Our team thrives on solving complex technical challenges, delighting our users, and setting a new standard for the industry.

About the role

Our engineering team tackles the toughest challenges so our users never have to. Real-time infrastructure, AI-native architecture, and a frontend that feels effortless — all powered by a team that moves fast, thinks rigorously, and holds an exceptionally high bar for quality.

We’re looking for a Web Infrastructure Engineer who lives and breathes the systems, runtimes, and tooling that enable engineers at Attio to ship fast and confidently. You’ll own performance across the stack — from the Node.js runtime and TypeScript pipelines to client-side rendering, bundling, and real-user metrics — and help shape the web infrastructure that powers Attio’s product.

What you’ll do

• Lead initiatives to improve performance in both the frontend (React, web workers, bundling) and backend (Node.js runtime, TypeScript pipelines, and I/O efficiency)

• Use profiling and benchmarking techniques to identify and eliminate bottlenecks and memory leaks in our Node.js services and client-side application code

• Build and integrate metrics, tracing, and performance dashboards to make performance data accessible and actionable across teams

• Reduce build and CI/CD overhead by optimising dependency management, incremental builds, caching strategies, and monorepo workflows

• Define internal best practices, guidelines, and tooling for the web infrastructure that scale with the company

• Represent Attio’s Product & Engineering values both internally and externally

What you'll bring

• Deep expertise in JavaScript and TypeScript performance on both client and server, including event-loop behaviour, garbage collection, async I/O, and memory management

• Proven experience designing and optimising internal API and service-layer architecture — particularly frameworks that coordinate data fetching, caching, and state management across large React/TypeScript codebases.

• Strong familiarity with performance tooling such as Chrome DevTools, Node profiler/inspector, flamegraphs, Lighthouse, APM platforms, and runtime exploration tools

• Strong understanding of frontend performance patterns (lazy loading, route-level splitting, bundle analysis, caching strategies, web workers)

• Experience using Real-User Metrics (RUM) to guide and prioritise performance improvements, and comfort working with tools such as Datadog, Sentry, Prometheus, Grafana, or OpenTelemetry

• Systems-level understanding of build and CI/CD pipelines (Yarn, pnpm, npm, esbuild, Vite, Turborepo, Rsbuild, incremental builds)

• Excellent communication skills and the ability to influence engineers across product teams to align on performance strategy

Nice to have:

• Experience with React internals, reconciliation debugging, or custom performance instrumentation

• Contributions to open-source infrastructure projects, performance tooling or JavaScript/TypeScript runtimes

• Familiarity with TypeScript compiler internals, V8 engine behaviour, or WebAssembly tooling

• Familiarity with Go, Rust and native profilers such as dtrace, xctrace and Linux perf

• Experience optimizing large-scale real-time or collaborative web applications

What we offer

• Equity in an early-stage tech company on an incredible trajectory

• 25 days holiday plus local public holidays

• Team off-site in fun places! (We've been to Barcelona, Lisbon, Malta, and Split so far)