One IIS Module, 45 Legacy Apps: Federated Identity Without Touching the Code
When a federated-identity mandate meant turning off Windows Authentication across 45 legacy ColdFusion apps, the obvious fix was to add an OIDC client to all 45 codebases. Instead I wrote a single IIS module in modern C# that handles the OIDC handshake at the server boundary and hands each app the same authenticated identity it always read, so not one line of application code had to change, and the later switch from ADFS to DUO was a one-module update.