CareerPlan

Senior Software Engineer, Workers Runtime

Austin, TXFull-time2026-07-10 → 2026-11-10
Based in United StatesNo visa sponsorshipU.S. persons only (export control)

Core

Building and optimizing the runtime that executes customer code at the edge, focusing on performance, reliability, and scale for JavaScript and WebAssembly.

Role type

Senior IC systems engineer (runtime)

Builds

The Cloudflare Workers Runtime

Domain

Cloud infrastructure / Edge computing / Distributed systems

Required skills

C++ or Rust, computer science fundamentals (data structures, algorithms, software design), operational mindset, deep web knowledge (HTTP, JavaScript, WebAssembly), debugging large-scale Linux distributed systems

Preferred skills

Rust high-performance distributed systems, cloud/serverless platforms, JS engine internals (V8, SpiderMonkey, JavaScriptCore), standalone WebAssembly runtimes (Wasmtime, Wasmer, Lucet), Linux/UNIX/kernel/networking knowledge, open source contributions

Technologies

C++, Rust, JavaScript, WebAssembly, HTTP, Linux, V8, SpiderMonkey, JavaScriptCore, Wasmtime, Wasmer, Lucet

Responsibilities

Build features and improvements for the Workers Runtime, Improve runtime performance, reliability, and scale, Expand JavaScript API and WebAssembly support, Help shape features based on technical feasibility, Own code in production and debug issues in a large-scale distributed system, Work in a fast-paced, iterative environment balancing product goals with technical execution

Seniority

Senior, hands-on IC