[pull] develop from mermaid-js:develop

.build/common.ts

@@ -31,7 +31,9 @@ export const packageOptions = {
   'mermaid-layout-elk': {
     name: 'mermaid-layout-elk',
     packageName: 'mermaid-layout-elk',
-    file: 'layouts.ts',
+    // Built from mermaid's own ELK source (path is relative to the package's
+    // `src`) so the plugin and the bundled layout are the same implementation.
+    file: '../../mermaid/src/rendering-util/layout-algorithms/elk/plugin.ts',
   },
   'mermaid-layout-tidy-tree': {
     name: 'mermaid-layout-tidy-tree',

.changeset/cluster-label-measurement.md

@@ -6,4 +6,4 @@ feat: `defaultMeasureLayout` accepts a `unwrapGroupLabels` option so a layout en
 
 `insertCluster` paints a plain cluster label with an infinite width while the measurement pass wrapped it at 200px, so a layout that sizes compound nodes from the measured label sized them too narrow. Layouts now opt in explicitly; core no longer inspects the layout's name. Markdown cluster labels stay wrapped, since those are painted wrapped.
 
-`@mermaid-js/layout-elk` opts in, which changes the size of labelled subgraphs in ELK-laid-out diagrams. Diagrams laid out with dagre are unaffected.
+The bundled ELK layout opts in, which changes the size of labelled subgraphs in ELK-laid-out diagrams. Diagrams laid out with dagre are unaffected.

.changeset/elk-composite-edge-anchor.md

@@ -0,0 +1,5 @@
+---
+'mermaid': patch
+---
+
+fix: keep ELK subgraph frames out to the border anchor of edges that terminate on the group, so transitions to composite states no longer run along the cluster border

.changeset/elk-container-algorithms.md

@@ -1,5 +1,5 @@
 ---
-'@mermaid-js/layout-elk': minor
+'mermaid': minor
 ---
 
 feat: let a container pick its own ELK algorithm with `@{ algorithm: … }`, and add `elk.box` and `elk.rectpacking` to the selectable `layout` values.

.changeset/elk-container-cycle-breaking.md

@@ -0,0 +1,19 @@
+---
+'mermaid': patch
+---
+
+fix(elk): a composite state or subgraph containing a loop now opens on its own start node.
+
+Cycle breaking was resolved for the root graph but never passed to containers, so a
+container laid out on its own fell back to ELK's default, `GREEDY`, while the root ran
+whatever `elk.preset` asked for. The two then reversed different edges of the same cycle.
+
+In a composite state that loops, greedy reverses the edge that turns an ordinary state
+into a source, and sources sit on the first layer — so the diagram opened on that state
+alongside its start circle instead of on the start circle alone. Dagre reverses the other
+edge, which is why the two layout engines disagreed on the same diagram.
+
+Containers now resolve cycle breaking from the preset exactly as the root does. Only
+containers that actually contain a cycle change; an acyclic subgraph gives a cycle-breaking
+strategy nothing to do. `preset: legacy` still reaches containers with `GREEDY`, so it keeps
+reproducing the earlier rendering inside frames as well as outside them.

.changeset/elk-default-layout.md

@@ -0,0 +1,28 @@
+---
+'mermaid': major
+---
+
+feat!: **ELK is now bundled with mermaid and is the default layout algorithm.**
+
+ELK previously shipped as a separate `@mermaid-js/layout-elk` package that sites had to install and register. It is now part of mermaid itself and registered automatically, so `layout: elk` — and the `elk.stress`, `elk.force`, `elk.mrtree`, `elk.sporeOverlap`, `elk.box` and `elk.rectpacking` variants — work with no setup.
+
+**This changes how existing diagrams look.** Flowchart, state, class, entity-relationship, requirement, use-case and agentflow diagrams that do not specify a `layout` are now laid out by ELK instead of dagre. To keep the previous layout, set dagre explicitly:
+
+```yaml
+---
+config:
+  layout: dagre
+---
+```
+
+or globally, `mermaid.initialize({ layout: 'dagre' })`.
+
+Mindmap is unchanged: it keeps laying out with cose-bilkent unless a layout is explicitly requested (in the tiny build, which ships neither ELK nor cose-bilkent, it falls back to dagre).
+
+Other notes:
+
+- ELK is loaded as a separate chunk in the ESM builds, so it is only fetched when a diagram actually uses it. The single-file IIFE build (`mermaid.min.js`) inlines it and grows by roughly 500 kB gzipped.
+- The **tiny** build deliberately omits ELK to stay small, and falls back to dagre for diagrams that ask for an ELK layout. Its size is unchanged.
+- `@mermaid-js/layout-elk` is no longer needed on normal builds — existing `mermaid.registerLayoutLoaders(elkLayouts)` calls keep working and can be removed. It is still published, and remains the way to add ELK to the tiny build.
+- `dist/mermaid.esm.min.mjs` now contains syntax that `es-module-lexer` (used by Vite) rejects with `content contains invalid JS syntax`. Bundler users are unaffected as long as they import the `mermaid` package specifier, which resolves to the core build; only builds that point Vite directly at that dist file need to switch to the package specifier or the core build.
+- State diagrams now resolve their layout through the same registration check as every other diagram, so an unavailable layout falls back instead of failing to render.

.changeset/elk-small-node-vertical-edges.md

@@ -0,0 +1,5 @@
+---
+'mermaid': patch
+---
+
+fix: keep ELK edges vertical at small nodes — the node now moves onto the routed line instead of the edge bending toward the node's off-centre position

.changeset/er-elk-edges-above-clusters.md

@@ -0,0 +1,5 @@
+---
+'mermaid': patch
+---
+
+fix: render ER relationship edges above subgraph backgrounds under the ELK layout instead of hiding them behind the cluster rect

.changeset/layout-elk-built-from-core.md

@@ -0,0 +1,13 @@
+---
+'@mermaid-js/layout-elk': minor
+---
+
+feat: this package is now built from mermaid's own ELK implementation instead of carrying its own copy, and is only needed for Mermaid builds that ship without ELK.
+
+`mermaid` bundles ELK and registers it automatically, so most projects can drop the dependency and the `registerLayoutLoaders` call. The package remains published and fully functional for the **tiny** build (`mermaid.tiny.js`), which omits ELK to stay small and where registering this is the only way to get an ELK layout.
+
+Because it is compiled from mermaid's ELK source rather than importing the whole `mermaid` entry point, the published bundle no longer drags in every diagram type, parser and KaTeX: the minified ESM payload drops from roughly **1.58 MB to 728 kB gzipped**. It stays self-contained, so it still loads from a CDN next to any Mermaid build with no import map.
+
+The rendering utilities the ELK source reaches (`dompurify`, `katex`, `dayjs`, `dagre-d3-es`) are now declared in the package's `dependencies`, so the npm build (`.core.mjs`) resolves them through your package manager — they dedupe against the host's copies and show up in audits — instead of carrying invisible inlined copies.
+
+> **Maintainers:** `peerDependencies.mermaid` still reads `^11.0.2`. It should be raised to the major that bundles ELK as part of the release.

.esbuild/util.ts

@@ -105,7 +105,8 @@ export const getBuildConfig = (options: MermaidBuildOptions): BuildOptions => {
   if (core) {
     // Core build is used to generate file without bundled dependencies.
     // This is used by downstream projects to bundle dependencies themselves.
-    // Ignore dependencies and any dependencies of dependencies
+    // Ignore dependencies and any dependencies of dependencies.
+    // A package may legitimately have none at all.
     //
     // peerDependencies must be external too. The consumer is the one that
     // supplies them, so inlining one ships a second copy of that package —

docs/config/layouts.md

@@ -10,19 +10,27 @@ This page lists the available layout algorithms supported in Mermaid diagrams.
 
 ## Supported Layouts
 
-- **elk**: [ELK (Eclipse Layout Kernel)](https://www.eclipse.org/elk/)
-- **tidy-tree**: Tidy tree layout for hierarchical diagrams [Tidy Tree Configuration](/config/tidy-tree)
-- **cose-bilkent**: Cose Bilkent layout for force-directed graphs
+- **elk** (default): [ELK (Eclipse Layout Kernel)](https://www.eclipse.org/elk/). Bundled with Mermaid; no setup required. Specific ELK algorithms can be selected as `elk.stress`, `elk.force`, `elk.mrtree`, `elk.sporeOverlap`, `elk.box`, and `elk.rectpacking`.
 - **dagre**: Dagre layout for layered graphs
+- **cose-bilkent**: Cose Bilkent layout for force-directed graphs
+- **tidy-tree**: Tidy tree layout for hierarchical diagrams, from the [`@mermaid-js/layout-tidy-tree`](https://www.npmjs.com/package/@mermaid-js/layout-tidy-tree) package [Tidy Tree Configuration](/config/tidy-tree)
+
+Mindmaps are the one diagram type not laid out with ELK by default; they use
+cose-bilkent unless you ask for something else.
+
+The **tiny** build omits ELK to stay small, and falls back to Dagre for
+diagrams that request it.
 
 ## How to Use
 
-You can specify the layout in your diagram's YAML config or initialization options. For example:
+Since `elk` is the default, a diagram needs no configuration to use it. To pick
+a different layout, set it in your diagram's YAML config or initialization
+options. For example:
 
 ```mermaid-example
 ---
 config:
-  layout: elk
+  layout: dagre
 ---
 graph TD;
   A-->B;
@@ -32,7 +40,7 @@ graph TD;
 ```mermaid
 ---
 config:
-  layout: elk
+  layout: dagre
 ---
 graph TD;
   A-->B;

docs/config/setup/mermaid/interfaces/LayoutLoaderDefinition.md

@@ -10,28 +10,28 @@
 
 # Interface: LayoutLoaderDefinition
 
-Defined in: [packages/mermaid/src/rendering-util/render.ts:24](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/rendering-util/render.ts#L24)
+Defined in: [packages/mermaid/src/rendering-util/render.ts:25](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/rendering-util/render.ts#L25)
 
 ## Properties
 
 ### algorithm?
 
 > `optional` **algorithm**: `string`
 
-Defined in: [packages/mermaid/src/rendering-util/render.ts:27](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/rendering-util/render.ts#L27)
+Defined in: [packages/mermaid/src/rendering-util/render.ts:28](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/rendering-util/render.ts#L28)
 
 ---
 
 ### loader
 
 > **loader**: `LayoutLoader`
 
-Defined in: [packages/mermaid/src/rendering-util/render.ts:26](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/rendering-util/render.ts#L26)
+Defined in: [packages/mermaid/src/rendering-util/render.ts:27](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/rendering-util/render.ts#L27)
 
 ---
 
 ### name
 
 > **name**: `string`
 
-Defined in: [packages/mermaid/src/rendering-util/render.ts:25](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/rendering-util/render.ts#L25)
+Defined in: [packages/mermaid/src/rendering-util/render.ts:26](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/rendering-util/render.ts#L26)