.env and config file tools

App configuration is spread across many small formats. Environment files (.env) hold KEY=value pairs that Docker Compose and dotenv libraries load into process environment variables. INI files group keys under [section] headers. JSONC adds comments to JSON for files like tsconfig.json and VS Code settings, and Kubernetes describes deployments in YAML manifests.

The .env format has no formal spec, so loaders disagree on quoting, escape sequences, inline comments and ${VAR} expansion. Every value is a string until your app parses it. Common production incidents come from a variable that exists in staging but not in production, a key defined twice where the last one wins without warning, or a secret pasted into a ticket or chat while debugging.

The tools below target those problems. Check a .env file for invalid names, broken quotes, duplicates and undefined references. Compare environments by which keys are present without showing values, and convert variables to nested JSON or YAML and back. Deep-merge a base config with overrides and see every changed path, redact passwords, tokens and keys before you share a file, convert INI to JSON, YAML or TOML, strip JSONC comments to get strict JSON, and preflight Kubernetes manifests. Everything runs in your browser.