HashiCorp Vault and TLS Certificate Authentication for .NET Applications

HashiCorp Vault is a tool for secrets management, encryption as a service, and privileged access management. It is quite popular nowadays, especially if you own your own infrastructure, private cloud or just cannot store your secrets using Key Vault services provided by Azure/AWS/GCP. I assume that you already have one up and running instance of HashiCorp Vault, otherwise you may install one using official Installing Vault guide.