Public exports & subpaths

Active contributors: Rich Harris, Ben McCann

Purpose

Everything user code can import from the package. Subpath exports are declared in packages/svelte/package.json#exports. Internal-only modules live behind subpaths that start with svelte/internal/...; user code is not expected to import these directly.

Top-level entries

Subpath	Browser entry	Server / default entry	Purpose
svelte	packages/svelte/src/index-client.js	packages/svelte/src/index-server.js	Lifecycle, context API, mount, flushSync, etc.
svelte/compiler	(UMD packages/svelte/compiler/index.js)	packages/svelte/src/compiler/index.js	compile, compileModule, parse, migrate, print.
svelte/server	—	packages/svelte/src/server/index.js	render() for SSR.
svelte/store	packages/svelte/src/store/index-client.js	packages/svelte/src/store/index-server.js	Legacy writable, readable, derived stores.
svelte/reactivity	packages/svelte/src/reactivity/index-client.js	packages/svelte/src/reactivity/index-server.js	SvelteMap, SvelteSet, SvelteDate, SvelteURL.
svelte/reactivity/window	packages/svelte/src/reactivity/window/index.js	packages/svelte/src/reactivity/window/index.js	Reactive innerWidth, scrollX, devicePixelRatio, etc. (browser-only).
svelte/transition	packages/svelte/src/transition/index.js	same	fade, fly, slide, scale, blur, crossfade, draw.
svelte/animate	packages/svelte/src/animate/index.js	same	flip animation.
svelte/easing	packages/svelte/src/easing/index.js	same	Standard easing functions (cubicIn, quintOut, ...).
svelte/motion	packages/svelte/src/motion/index.js	same	Spring, Tween, plus the deprecated spring, tweened.
svelte/attachments	packages/svelte/src/attachments/index.js	same	attachment() key for the {@attach} directive.
svelte/events	packages/svelte/src/events/index.js	same	on(target, event, handler) typed event helper.
svelte/legacy	packages/svelte/src/legacy/legacy-client.js	packages/svelte/src/legacy/legacy-server.js	Svelte 4 compatibility shims (createClassComponent).
svelte/elements	type-only (packages/svelte/elements.d.ts)	type-only	DOM type augmentations for HTML/SVG/MathML.
svelte/action	type-only	type-only	The Action/ActionReturn types.

Internal subpaths

These are imported by compiled component code only (the compiler's transformers emit imports against them). Application code should not import them.

Subpath	What it is
svelte/internal/client	All the runtime helpers — mount, state, derived, blocks, bindings, transitions glue.
svelte/internal/server	The server Renderer and helper functions.
svelte/internal/disclose-version	Tiny module that re-exports PUBLIC_VERSION to gate version-dependent behaviour.
svelte/internal/flags/async	Sets async_mode_flag = true (compiler emits this when async features are used).
svelte/internal/flags/legacy	Same, for legacy mode.
svelte/internal/flags/tracing	Same, for tracing mode.

Workspace imports aliases

packages/svelte/package.json#imports declares aliases for use inside the package:

Alias	Resolves to
#client	packages/svelte/src/internal/client/types.d.ts
#client/constants	packages/svelte/src/internal/client/constants.js
#compiler	packages/svelte/src/compiler/private.d.ts (types) / index.js (default)
#compiler/builders	packages/svelte/src/compiler/utils/builders.js
#server	packages/svelte/src/internal/server/types.d.ts
#shared	packages/svelte/src/internal/shared/types.d.ts

Use these for internal imports — they keep relative paths short and avoid surface-area leakage.

Top-level types

packages/svelte/src/index.d.ts defines Component, ComponentType, SvelteComponent, MountOptions, Snippet, etc. After a build these are rolled up into packages/svelte/types/index.d.ts via dts-buddy.

See also

• Compiler — what svelte/compiler exposes.
• Client runtime — what svelte/internal/client actually does at runtime.
• Server runtime — what svelte/server does for SSR.
• Features section — for svelte/transition, svelte/motion, svelte/store, svelte/attachments.