It turns out NODE_OPTIONS does not support most options in Azure functions. I’m currently working on a migration from AWS to Azure. While adding observability to Azure Functions (we use NODE_OPTIONS to bootstrap OpenTelemetry so it monkeypatches http/https properly) our functions stopped working. Logs in Azure only showed it was preparing to start up and nothing else. Using func start --verbose locally it finally said ‘unsupported option for NODE_OPTIONS’. The Azure Function documentation shows you can use languageWorkers__node__arguments instead.