A growing collection of copper web dot and articles.
Lightweight update server for Electron apps
stdio-to-HTTP MCP proxy for Grackle — bridges stdio-only MCP clients (Claude Desktop, Codex CLI, Clawpilot) to a Grackle HTTP MCP server using static API-key auth
A flexible React component library.
MCP (Model Context Protocol) server for Grackle — translates MCP tool calls to ConnectRPC
A Babel preset for each environment.
Offers getProxyForUrl to get the proxy URL for a URL, respecting the *_PROXY (e.g. HTTP_PROXY) and NO_PROXY environment variables.
AWS credential provider that sources credentials from known environment variables
Runtime agnostic JS utils
Run scripts that set and use environment variables across platforms
Convert modern CSS into something browsers understand
Loads environment variables from .env file
Next.js dotenv file loading
A global executable to run applications with the ENV variables loaded by dotenv
hydrate environment variables from .env files into process.env
Executes a command using the environment variables in an env file
Get the PATH environment variable key cross-platform
Uses export conditions to return environment information in a way that works with major bundlers and runtimes.
Get paths for storing things like data, config, cache, etc
A Babel preset that targets modern browsers by fixing engine bugs.
Regular expression for matching a shebang line
Use env() variables in CSS
HANDLE CONFIGURATION ONCE AND FOR ALL
 [](https://jsr.io/@t3-oss/env-core) [](https://jsr.io/@t3-oss/env-core) [![Socket Bad