@webiny/stdlib

Opinionated standard library for Webiny. This is an internal package — we make breaking changes freely and do not follow semver for external consumers.

Design

Services are built on a lightweight dependency injection system. Each feature follows the same three-layer pattern: an abstraction (DI token + interface), an implementation (concrete class), and a feature (registers the implementation in the DI container). This keeps code testable and lets different environments (Node.js, browser) swap implementations behind the same interface.

Subpath exports

The package is ESM-only and ships three subpath exports. Because each is a separate entry point, Node.js-specific code is never bundled into a browser build and vice versa — unless you explicitly import the wrong subpath.

| Import | Environment | Description | | ------------------------ | ----------- | --------------------------- | | @webiny/stdlib | Any | Platform-agnostic utilities | | @webiny/stdlib/node | Node.js | Node.js-specific tools | | @webiny/stdlib/browser | Browser | Browser-specific tools | | @webiny/stdlib/mcp | Node.js | MCP server + agent config |

@webiny/stdlib — Common

| Feature | Description | | ------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------ | | Result / ResultAsync | Typed success/failure values — synchronous and async | | BaseError | Abstract base class for typed domain errors | | Logger / ConsoleLogger / ConsoleLoggerFeature | Logging abstraction + console implementation — docs | | Cache / MemoryCacheFeature | Synchronous key-value cache — docs | | AsyncCache / AsyncMemoryCacheFeature | Async key-value cache — docs | | immutableGet / immutableSet / immutableDelete / mutableSet / mutableDelete | Dot-notation get/set/delete on nested objects — docs | | toBoolean / isTruthy / isFalsy | Semantic boolean coercion — docs | | uuid | RFC 4122 v4 UUID generator (native + fallback) — docs | | mdbid | MongoDB-compatible ObjectId generator — docs | | generateId / generateAlphaNumericId / generateAlphaLowerCaseId / ... | Nanoid-based ID generators with configurable alphabets — docs | | Env | Typed environment variable access (abstraction) — docs |

@webiny/stdlib/node — Node.js

| Feature | Description | | ---------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------- | | FileTool / FileToolFeature | Read, write, copy, remove files — docs | | DirectoryTool / DirectoryToolFeature | Create, read, remove, copy, glob directories — docs | | JsonFileTool / JsonFileToolFeature | Read and write JSON files with optional schema validation — docs | | PathTool / PathToolFeature | node:path wrapper + resolvePackageFile for package-relative paths — docs | | PinoLogger / PinoLoggerFeature | pino-based Logger implementation — docs | | NdJsonReaderTool / NdJsonReaderToolFeature | Parse NDJSON from files, streams, or in-memory lines with checkpoint support — docs | | ReadStreamFactory / ReadStreamFactoryFeature | node:fs read streams with explicit destroy() cleanup — docs | | PackageJsonFileTool / PackageJsonFileToolFeature | Read, validate, mutate, and write package.json files — docs | | HashFolderTool / HashFolderToolFeature | Deterministic SHA-256 hash of a folder's contents — docs | | ProcessEnvFeature | Env implementation backed by process.env — docs | | WorkspaceTool / WorkspaceToolFeature | Discover workspaces from root package.json (replaces get-yarn-workspaces) — docs | | GlobTool / GlobToolFeature | Find files and directories by glob pattern — docs |

@webiny/stdlib/browser — Browser

| Feature | Description | | -------------------------- | ----------------------------------------------------------------------------------------------------------------- | | LocalStorageCacheFeature | Cache implementation backed by window.localStorage — docs | | BrowserEnvFeature | Env implementation backed by an injected variables object — docs |

@webiny/stdlib/mcp — MCP Server

An MCP server that exposes @webiny/stdlib feature documentation as tools for AI agent discovery. Ships a CLI binary (stdlib-mcp) with two commands:

# Start the MCP server (stdio transport)
npx -y @webiny/stdlib stdlib-mcp serve

# Configure an AI agent (Claude Code, Cursor, Cline, Copilot, Windsurf, Kiro, OpenCode)
npx -y @webiny/stdlib stdlib-mcp configure

The server provides two MCP tools: list_stdlib_skills (grouped catalog of all features) and get_stdlib_skill (full documentation for a specific skill). By default it scans skills/ and src/ (or dist/) for README.md and SKILL.md files with YAML front-matter.

| Feature | Description | | ------------------------------------------------ | ----------------------------------------------------------------------------------------------- | | McpServer / McpServerFeature | MCP server with stdio transport — docs | | SkillDiscovery / SkillDiscoveryConfig | Scans directories for skill files with front-matter — docs | | AgentConfigurator / AgentConfiguratorFeature | Interactive CLI to configure AI agents — docs |

Versioning

Versioning and publishing are managed by Changesets. The version in package.json is the real published version, bumped automatically when a version PR is merged. To record a version bump, run yarn changeset before opening a PR. There are no major version bumps — breaking changes may land on minor releases.