As I’ve written before, I’m leaning heavily into immutability in the election site code. Until September 2025 (it’s taken a long time to get round to writing this blog post) that meant a combination of records, ImmutableList<T> and ImmutableDictionary<TKey, TValue>. In an ECMA C# standards meeting, however, Joseph Musser passed on some really valuable feedback … Continue reading Changing Immutable Collections →