zigxll: building Excel XLL add-ins in Zig

The Excel C SDK dates from the early 1990s. Memory management is manual, the type system is painful, and there’s almost no tooling. Despite all of this, it remains the only way to build add-ins that run truly in-process with Excel, supporting multi-threaded recalculation and the full breadth of what the host application can do. If you want the best possible performance, you need an XLL. But it’s a foot gun....

March 10, 2026 · Alex Reid

NATS as a web application backend

I have used NATS on various projects over the years. It provides a high performance transport layer than can be used to connect applications and services. If you haven’t already heard of it, this video is a fantastic primer. NATS supports websocket connections. nats.ws runs in browsers. This means we can directly use NATS as the backend for browser-based applications that need to display realtime streams of data. Why is this interesting?...

May 14, 2023 · Alex Reid