HMPL.js is a lightweight JavaScript library for server-oriented HTML templating. It compiles templates with block helpers (e.g., `{{#request ...}}`) into functions that fetch HTML from a server, sanitize it via DOMPurify, and render it into the DOM. The library supports indicators, memoization, intervals, and status binding, and uses JSON5 for expressive attribute parsing. The core is a single TypeScript module (`src/main.ts`) that exports `compile`, `stringify`, `createWarning`, and `createError`. The repository also contains a comprehensive documentation site built with Astro + Starlight (including Vue interactive components) and a Jekyll blog. The codebase is well-tested with Mocha, Sinon, nock, and jsdom, and has CI/CD via GitHub Actions. It is primarily a frontend library but includes robust build and test infrastructure.