Deno Land has announced the release of Deno 2.2, a major update to the Deno runtime for JavaScript and TypeScript. This latest version introduces several significant features, including built-in OpenTelemetry for monitoring logs, metrics, and traces, as well as a major upgrade to the Deno linter.

The built-in OpenTelemetry feature allows developers to automatically instrument APIs such as console.log, Deno.serve, and fetch, providing a seamless way to capture observability data. Additionally, users can instrument their own code using npm:@opentelemetry/api and provide an OpenTelemetry protocol (OTLP) endpoint to capture the data. For development and test environments, Deno Land recommends using Grafana's LGTM Docker image.

The Deno linter has also received a significant upgrade, featuring a new plugin system and 15 new rules specifically designed for React and Preact users. These rules include jsx-boolean-value, jsx-button-has-type, and jsx-curly-braces, among others, aimed at improving code quality and reducing errors.

In terms of performance, Deno 2.2 has made several improvements, including clearing information about module analysis after a timeout, which leads to lower memory consumption. Additionally, Deno.stat and node:fs.stat are now up to 2.5 times faster on Windows, and Node.js module resolution has been optimized by limiting conversions between URLs and paths.

Other notable features in Deno 2.2 include a highly requested node:sqlite module for working with in-memory or local databases, improvements to deno lsp for faster and more responsive performance, and a more precise deno bench tool for benchmarking code. The deno check tools for type checking now respect JSDoc tags and allow compiler options to be configured per workspace member.

Furthermore, Deno 2.2 has made performance and quality of life improvements to deno compile, which is now smaller and faster. The release also upgrades to TypeScript 5.7 and features a revamped WebGPU implementation, expected to improve the performance of available APIs.

The release of Deno 2.2 demonstrates the platform's continued focus on performance, security, and developer experience. With its built-in OpenTelemetry and upgraded linter, Deno 2.2 is poised to become a go-to choice for developers building modern web applications.

Existing users can upgrade to Deno 2.2 by running the command deno upgrade, while new users can find installation instructions on the Deno Land website.

As the JavaScript ecosystem continues to evolve, Deno 2.2's new features and improvements are likely to have a significant impact on the development community. With its focus on performance, security, and ease of use, Deno is well-positioned to remain a major player in the JavaScript runtime market.