Mathapedia · pyramation · Aug 17, 2026 · Aug 17, 2026 · Aug 18, 2026 · Aug 23, 2026
diff --git a/.gitignore b/.gitignore
@@ -1 +1,6 @@
-static
+node_modules/
+.next/
+out/
+next-env.d.ts
+tsconfig.tsbuildinfo
+.DS_Store
diff --git a/README.md b/README.md
@@ -0,0 +1,26 @@
+# latex2js.com
+
+The website for [LaTeX2JS](https://github.com/Mathapedia/LaTeX2JS) — author interactive math equations and diagrams online using LaTeX and PSTricks.
+
+Built with Next.js (static export) on the same architecture as [constructive.io](https://constructive.io) and [danlynch.com](https://danlynch.com):
+
+- **JSON-LD knowledge graph** — `src/data/jsonld/` holds a flat graph of schema.org entities with namespaced `@id`s (`software:latex2js`, `org:constructive`, `person:danlynch`, …) shared across the site family. Pages slice per-page subgraphs via `jsonldjs` and the `<Head>` component injects them as `application/ld+json`.
+- **SEO registry** — `src/seo.ts` holds per-route titles/descriptions; canonicals are derived from typed routes.
+- **Sitemap + robots.txt** — generated post-build from the exported HTML by `src/seo/seo.ts`.
+- **llms.txt + markdown twins** — `scripts/generate-llm-markdown.ts` emits `out/llms.txt` and a `.md` twin for every example and installation page.
+- **Content as data** — the interactive PSTricks examples live as `.tex` files in `content/examples/`, registered in `src/data/examples.ts`, and rendered client-side by [`@latex2js/react`](https://www.npmjs.com/package/@latex2js/react).
+
+## Develop
+
+```bash
+pnpm install
+pnpm dev        # http://localhost:5007
+pnpm test       # JSON-LD graph validation + registry tests
+```
+
+## Build & deploy
+
+```bash
+pnpm build      # next build + llms.txt/md twins + sitemap/robots into out/
+pnpm deploy:all # build, sync to s3://latex2js.com, extensionless copies, CloudFront invalidation
+```
diff --git a/__tests__/helpers/jsonld-test-utils.ts b/__tests__/helpers/jsonld-test-utils.ts
@@ -0,0 +1,97 @@
+/**
+ * JSON-LD Test Utilities
+ *
+ * Helper functions for testing JSON-LD output.
+ * Snapshots are kept lean by extracting only @id and @type properties.
+ */
+
+import { type JsonLdGraph, type JsonLdEntity } from 'jsonldjs';
+
+/**
+ * Extract only @id properties from entities for lean snapshots
+ */
+export function extractIds(entities: JsonLdEntity[]): string[] {
+	return entities
+		.map((e) => e['@id'])
+		.filter((id): id is string => typeof id === 'string')
+		.sort();
+}
+
+/**
+ * Extract @id and @type for more detailed snapshots
+ */
+export function extractIdsAndTypes(entities: JsonLdEntity[]): { id: string; type: string | string[] }[] {
+	return entities
+		.map((e) => ({
+			id: e['@id'],
+			type: e['@type'] as string | string[],
+		}))
+		.filter((e): e is { id: string; type: string | string[] } => typeof e.id === 'string')
+		.sort((a, b) => a.id.localeCompare(b.id));
+}
+
+/**
+ * Group entities by @type
+ */
+export function groupByType(entities: JsonLdEntity[]): Record<string, string[]> {
+	const grouped: Record<string, string[]> = {};
+
+	for (const entity of entities) {
+		const type = entity['@type'];
+		const id = entity['@id'];
+
+		if (!id) continue;
+
+		const types = Array.isArray(type) ? type : [type];
+		for (const t of types) {
+			if (t) {
+				if (!grouped[t]) grouped[t] = [];
+				grouped[t].push(id);
+			}
+		}
+	}
+
+	// Sort IDs within each type
+	for (const type of Object.keys(grouped)) {
+		grouped[type].sort();
+	}
+
+	return grouped;
+}
+
+/**
+ * Create a summary of the JSON-LD graph
+ */
+export interface JsonLdSummary {
+	totalEntities: number;
+	entityIds: string[];
+	byType: Record<string, string[]>;
+}
+
+export function createJsonLdSummary(entities: JsonLdEntity[]): JsonLdSummary {
+	return {
+		totalEntities: entities.length,
+		entityIds: extractIds(entities),
+		byType: groupByType(entities),
+	};
+}
+
+/**
+ * Filter entities that have usesSoftware referencing a specific software ID
+ */
+export function findOrganizationsUsingSoftware(entities: JsonLdEntity[], softwareId: string): string[] {
+	return entities
+		.filter((entity) => {
+			if (entity['@type'] !== 'Organization') return false;
+			const usesSoftware = entity.usesSoftware;
+			if (!usesSoftware) return false;
+
+			const refs = Array.isArray(usesSoftware) ? usesSoftware : [usesSoftware];
+			return refs.some((ref) => {
+				const refId = typeof ref === 'string' ? ref : ref?.['@id'];
+				return refId === softwareId;
+			});
+		})
+		.map((e) => e['@id'] as string)
+		.sort();
+}
diff --git a/__tests__/jsonld/__snapshots__/graph-validation.test.ts.snap b/__tests__/jsonld/__snapshots__/graph-validation.test.ts.snap
@@ -0,0 +1,33 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`JSON-LD Graph Validation Graph Integrity should have consistent entity count 1`] = `
+{
+  "totalEntities": 24,
+}
+`;
+
+exports[`JSON-LD Graph Validation findMissingReferences should find missing references in the graph 1`] = `[]`;
+
+exports[`JSON-LD Graph Validation findNestedEntities should find nested entities in the graph 1`] = `[]`;
+
+exports[`JSON-LD Graph Validation findOrphans should find orphaned entities in the graph 1`] = `
+[
+  "software:latex2js-react",
+  "software:latex2js-vue",
+  "webpage:latex2js-example-block-diagram",
+  "webpage:latex2js-example-complex-plane",
+  "webpage:latex2js-example-custom-path",
+  "webpage:latex2js-example-derivative-story",
+  "webpage:latex2js-example-draggable-vector",
+  "webpage:latex2js-example-feedback-system",
+  "webpage:latex2js-example-function-plot",
+  "webpage:latex2js-example-geometric-series",
+  "webpage:latex2js-example-interactive-plot",
+  "webpage:latex2js-example-sampling-system",
+  "webpage:latex2js-example-shaded-integral",
+  "webpage:latex2js-example-two-variables",
+  "webpage:latex2js-example-unit-circle",
+  "webpage:latex2js-example-vector-functions",
+  "website:latex2js.com",
+]
+`;
diff --git a/__tests__/jsonld/examples-registry.test.ts b/__tests__/jsonld/examples-registry.test.ts
@@ -0,0 +1,32 @@
+/**
+ * Examples registry tests
+ *
+ * The examples registry drives routes, JSON-LD entities, and llms.txt —
+ * every entry must point at a real .tex file and have a unique slug.
+ */
+
+import fs from 'fs';
+import path from 'path';
+
+import { examples } from '@/data/examples';
+
+const CONTENT_DIR = path.resolve(__dirname, '../../content/examples');
+
+describe('Examples registry', () => {
+	it('every example points to an existing .tex file', () => {
+		examples.forEach((example) => {
+			expect(fs.existsSync(path.join(CONTENT_DIR, example.file))).toBe(true);
+		});
+	});
+
+	it('every .tex file is registered exactly once', () => {
+		const texFiles = fs.readdirSync(CONTENT_DIR).filter((f) => f.endsWith('.tex'));
+		const registered = examples.map((e) => e.file).sort();
+		expect(registered).toEqual(texFiles.sort());
+	});
+
+	it('slugs are unique', () => {
+		const slugs = examples.map((e) => e.slug);
+		expect(new Set(slugs).size).toBe(slugs.length);
+	});
+});
diff --git a/__tests__/jsonld/graph-validation.test.ts b/__tests__/jsonld/graph-validation.test.ts
@@ -0,0 +1,85 @@
+/**
+ * JSON-LD Graph Validation Tests
+ *
+ * Tests for graph integrity - checking for missing references,
+ * nested entities, orphans, and duplicates.
+ */
+
+import { findMissingReferences, findNestedEntities, findOrphans } from 'jsonldjs';
+
+import { jsonldGraph } from '@/data/jsonld';
+
+describe('JSON-LD Graph Validation', () => {
+	describe('findMissingReferences', () => {
+		it('should find missing references in the graph', () => {
+			const missingRefs = findMissingReferences(jsonldGraph);
+
+			if (missingRefs.length > 0) {
+				console.log('Missing references found:', missingRefs.length);
+				console.log('First 10 missing references:', missingRefs.slice(0, 10));
+			}
+
+			expect(missingRefs.sort()).toMatchSnapshot();
+		});
+	});
+
+	describe('findNestedEntities', () => {
+		it('should find nested entities in the graph', () => {
+			const nestedEntities = findNestedEntities(jsonldGraph);
+
+			const summary = nestedEntities.map((n) => ({
+				parentId: n.parentId,
+				property: n.property,
+				hasId: n.hasId,
+				type: n.nestedEntity['@type'],
+			}));
+
+			expect(summary).toMatchSnapshot();
+		});
+	});
+
+	describe('findOrphans', () => {
+		it('should find orphaned entities in the graph', () => {
+			const orphans = findOrphans(jsonldGraph);
+
+			if (orphans.length > 0) {
+				console.log('Orphaned entities found:', orphans.length);
+				console.log('First 10 orphaned entities:', orphans.slice(0, 10));
+			}
+
+			expect(orphans.sort()).toMatchSnapshot();
+		});
+	});
+
+	describe('Graph Integrity', () => {
+		it('should track duplicate IDs in the graph', () => {
+			const ids = jsonldGraph.map((e) => e['@id']).filter(Boolean);
+			const duplicates = ids.filter((id, index) => ids.indexOf(id) !== index);
+			const uniqueDuplicates = [...new Set(duplicates)].sort();
+
+			expect(uniqueDuplicates).toEqual([]);
+		});
+
+		it('should have software:latex2js in the graph', () => {
+			const latex2js = jsonldGraph.find((e) => e['@id'] === 'software:latex2js');
+			expect(latex2js).toBeDefined();
+			expect(latex2js?.['@type']).toBe('SoftwareApplication');
+		});
+
+		it('should have website:latex2js.com in the graph', () => {
+			const website = jsonldGraph.find((e) => e['@id'] === 'website:latex2js.com');
+			expect(website).toBeDefined();
+			expect(website?.['@type']).toBe('WebSite');
+		});
+
+		it('should have no missing references', () => {
+			expect(findMissingReferences(jsonldGraph)).toEqual([]);
+		});
+
+		it('should have consistent entity count', () => {
+			expect({
+				totalEntities: jsonldGraph.length,
+			}).toMatchSnapshot();
+		});
+	});
+});
diff --git a/assets/css/latex2js.css b/assets/css/latex2js.css
diff --git a/assets/css/website.css b/assets/css/website.css