workerd is Cloudflare's open-source JavaScript and WebAssembly runtime, designed to execute code compatibly across various environments, from local development to serverless platforms. It mimics the Cloudflare Workers environment, providing a consistent platform for building and deploying applications without vendor lock-in. It offers features like KV storage emulation and supports standard web APIs, making it a robust choice for modern web development and serverless architectures.
Workerd's release frequency shows a fluctuating pattern. Initially sporadic in 2022, releases became more consistent throughout 2023 and 2024. A surge in releases occurred from April to August 2025, with April recording the highest at 29. September 2025 has only 4 releases so far.
Workerd's npm package downloads show strong growth from March 2024 to August 2025, increasing from 1.7M to 8.2M. 2025 saw a significant surge. September 2025's partial data currently indicates 1.4M downloads, suggesting a potentially lower total compared to the previous months due to the month not being complete yet.
