std-env

Runtime-agnostic JS utils for detecting environments, runtimes, CI providers, and AI coding agents.

Runtime Detection

Detects the current JavaScript runtime based on global variables, following the WinterCG Runtime Keys proposal.

import { runtime, runtimeInfo } from "std-env";

console.log(runtime); // "" | "node" | "deno" | "bun" | "workerd" ...
console.log(runtimeInfo); // { name: "node" }

Individual named exports: isNode, isBun, isDeno, isNetlify, isEdgeLight, isWorkerd, isFastly

Note

isNode is also true in Bun/Deno with Node.js compatibility mode. Use runtime === "node" for strict checks.

See ./src/runtimes.ts for the full list.

Provider Detection

Detects the current CI/CD provider based on environment variables.

import { isCI, provider, providerInfo } from "std-env";

console.log({ isCI, provider, providerInfo });
// { isCI: true, provider: "github_actions", providerInfo: { name: "github_actions", ci: true } }

Use detectProvider() to re-run detection. See ./src/providers.ts for the full list.

Agent Detection

Detects if the environment is running inside an AI coding agent.

import { isAgent, agent, agentInfo } from "std-env";

console.log({ isAgent, agent, agentInfo });
// { isAgent: true, agent: "claude", agentInfo: { name: "claude" } }

Set the AI_AGENT env var to explicitly specify the agent name. Use detectAgent() to re-run detection.

Supported agents: cursor, claude, devin, replit, gemini, codex, auggie, opencode, kiro, goose, pi

Flags

import { env, isDevelopment, isProduction } from "std-env";

Export	Description
hasTTY	stdout TTY is available
hasWindow	Global window is available
isCI	Running in CI
isColorSupported	Terminal color output supported
isDebug	DEBUG env var is set
isDevelopment	NODE_ENV is dev/development or MODE is development
isLinux	Linux platform
isMacOS	macOS (darwin) platform
isMinimal	MINIMAL env is set, CI, test, or no TTY
isProduction	NODE_ENV or MODE is production
isTest	NODE_ENV is test or TEST env is set
isWindows	Windows platform
platform	Value of process.platform
nodeVersion	Node.js version string (e.g. "22.0.0")
nodeMajorVersion	Node.js major version number (e.g. 22)

See ./src/flags.ts for details.

Environment

Export	Description
env	Universal process.env (works across all runtimes)
process	Universal process shim (works across all runtimes)
nodeENV	Current NODE_ENV value (undefined if unset)

License

MIT