xllify

Excel runs more business logic than any other piece of software. The problem is what happens when you need to go beyond what's built in. VBA is a dead end. C++ XLLs require specialist knowledge and a painful build toolchain. Python wrappers are heavyweight and hard to deploy. Office.js runs in a browser sandbox and feels nothing like native Excel.

xllify takes a different approach. Write functions in Luau (Roblox's production-hardened fork of Lua), and xllify compiles them to bytecode and bundles everything into a self-contained XLL (here's some more in-depth notes on how xllify add-in security) or Office.js add-in. No runtime to install, no environment to manage. It ships as a single file and works on Windows, Mac, and the web.

The company

xllify is built and maintained by Lexvica Limited, a small software company based in the north-east of England, founded in 2025. We offer consulting around data engineering, streaming, and Excel-adjacent tooling alongside the xllify product.