How does configuration work in .NET Core?

Updated Feb 20, 2026

Short answer

Configuration is managed using multiple providers like JSON files, environment variables, and command-line arguments.

Deep explanation

Configuration is hierarchical and supports reload-on-change. Common sources:

  • appsettings.json
  • appsettings.{Environment}.json
  • Environment variables

Real-world example

Different DB connection strings for dev, staging, and production.

Common mistakes

  • - Hardcoding secrets
  • - Not using environment configs

Follow-up questions

  • How would you scale this?
  • What are trade-offs?

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