diff --git a/src/content.config.ts b/src/content.config.ts
new file mode 100644
index 0000000..8d3fd62
--- /dev/null
+++ b/src/content.config.ts
@@ -0,0 +1,105 @@
+import { defineCollection, reference } from "astro:content";
+import { glob } from "astro/loaders";
+import { z } from "astro/zod";
+
+function removeDupsAndLowerCase(array: string[]) {
+	return [...new Set(array.map((str) => str.toLowerCase()))];
+}
+
+const titleSchema = z.string().max(60);
+
+const baseSchema = z.object({
+	title: titleSchema,
+});
+
+// Experiences double as a taxonomy: projects, writing & speaking reference them
+// by id so each experience page can render everything filed under it.
+const experienceRefs = z.array(reference("experience")).default([]);
+
+// /writing section.
+const writing = defineCollection({
+	loader: glob({ base: "./src/content/writing", pattern: "**/*.{md,mdx}" }),
+	schema: ({ image }) =>
+		baseSchema.extend({
+			description: z.string(),
+			coverImage: z
+				.object({
+					alt: z.string(),
+					src: image(),
+				})
+				.optional(),
+			draft: z.boolean().default(false),
+			ogImage: z.string().optional(),
+			tags: z.array(z.string()).default([]).transform(removeDupsAndLowerCase),
+			experiences: experienceRefs,
+			// External articles (PESOS): link out to the publisher instead of a local page.
+			externalUrl: z.url().optional(),
+			publisher: z.string().optional(), // e.g. "Fast Company", "Medium"
+			publishDate: z
+				.string()
+				.or(z.date())
+				.transform((val) => new Date(val)),
+			updatedDate: z
+				.string()
+				.optional()
+				.transform((str) => (str ? new Date(str) : undefined)),
+			pinned: z.boolean().default(false),
+		}),
+});
+
+// /projects section.
+const projects = defineCollection({
+	loader: glob({ base: "./src/content/projects", pattern: "**/*.{md,mdx}" }),
+	schema: ({ image }) =>
+		baseSchema.extend({
+			description: z.string().optional(),
+			coverImage: z
+				.object({
+					alt: z.string(),
+					src: image(),
+				})
+				.optional(),
+			link: z.url().optional(),
+			repo: z.url().optional(),
+			// Skills double as tags for cross-project categorization.
+			tags: z.array(z.string()).default([]).transform(removeDupsAndLowerCase),
+			experiences: experienceRefs,
+			startDate: z.coerce.date(),
+			endDate: z.coerce.date().optional(), // omit for ongoing projects
+		}),
+});
+
+// Experience = resume entries that also act as the taxonomy for the site.
+const experience = defineCollection({
+	loader: glob({ base: "./src/content/experience", pattern: "**/*.{md,mdx}" }),
+	schema: baseSchema.extend({
+		organization: z.string(),
+		role: z.string().optional(),
+		location: z.string().optional(),
+		url: z.url().optional(),
+		description: z.string().optional(),
+		// Skills double as site-wide tags (see /tags).
+		tags: z.array(z.string()).default([]).transform(removeDupsAndLowerCase),
+		startDate: z.coerce.date(),
+		endDate: z.coerce.date().optional(), // omit for current/ongoing
+	}),
+});
+
+// Speaking = talks/presentations rendered with an embedded YouTube player.
+const speaking = defineCollection({
+	loader: glob({ base: "./src/content/speaking", pattern: "**/*.{md,mdx}" }),
+	schema: baseSchema.extend({
+		description: z.string(),
+		youtubeId: z.string(), // YouTube video ID
+		event: z.string().optional(),
+		draft: z.boolean().default(false),
+		tags: z.array(z.string()).default([]).transform(removeDupsAndLowerCase),
+		experiences: experienceRefs,
+		publishDate: z
+			.string()
+			.or(z.date())
+			.transform((val) => new Date(val)),
+	}),
+});
+
+export const collections = { writing, projects, experience, speaking };