Gotenberg
Developer-friendly API to interact with powerful tools like Chromium and LibreOffice for converting numerous document formats (HTML, Markdown, Word, Excel, etc.) into PDF files, and more. (Source Code) MIT Docker
Perform all manner of operations within a web browser such as AES, DES and Blowfish encryption and decryption, creating hexdumps, calculating hashes, and much more. (Demo) Apache-2.0 Javascript