diff --git a/packages/shared/package.json b/packages/shared/package.json
index af89eb4..256acb2 100644
--- a/packages/shared/package.json
+++ b/packages/shared/package.json
@@ -8,5 +8,8 @@
   },
   "exports": {
     ".": "./src/index.ts"
+  },
+  "dependencies": {
+    "zod": "^4.3.6"
   }
 }
diff --git a/packages/shared/src/index.ts b/packages/shared/src/index.ts
index 548d69e..2137233 100644
--- a/packages/shared/src/index.ts
+++ b/packages/shared/src/index.ts
@@ -1 +1,2 @@
 export * from "./constants.js";
+export * from "./schema.js";
diff --git a/packages/shared/src/schema.ts b/packages/shared/src/schema.ts
new file mode 100644
index 0000000..c3274c7
--- /dev/null
+++ b/packages/shared/src/schema.ts
@@ -0,0 +1,72 @@
+import * as z from "zod";
+
+export const Term = z.object({
+  id: z.uuid(),
+  synset_id: z.string(),
+  pos: z.string(),
+  created_at: z.iso.datetime(),
+});
+
+export type Term = z.infer<typeof Term>;
+
+export const Translation = z.object({
+  id: z.uuid(),
+  term_id: z.string(),
+  language_code: z.string(),
+  text: z.string(),
+  created_at: z.iso.datetime(),
+});
+
+export type Translation = z.infer<typeof Translation>;
+
+export const TermGloss = z.object({
+  id: z.uuid(),
+  term_id: z.uuid(),
+  language_code: z.string(),
+  text: z.string(),
+  created_at: z.iso.datetime(),
+});
+
+export type TermGloss = z.infer<typeof TermGloss>;
+
+export const LanguagePair = z.object({
+  id: z.uuid(),
+  source_language: z.string(),
+  target_language: z.string(),
+  label: z.string(),
+  active: z.boolean(),
+  created_at: z.iso.datetime(),
+});
+
+export type LanguagePair = z.infer<typeof LanguagePair>;
+
+export const User = z.object({
+  id: z.uuid(),
+  openauth_sub: z.string(),
+  email: z.email(),
+  display_name: z.string(),
+  created_at: z.iso.datetime(),
+  last_login_at: z.iso.datetime(),
+});
+
+export type User = z.infer<typeof User>;
+
+export const Deck = z.object({
+  id: z.uuid(),
+  name: z.string(),
+  desciption: z.string(),
+  source_language: z.string(),
+  validated_languages: z.array(z.string()),
+  is_public: z.boolean(),
+  created_at: z.iso.datetime(),
+});
+
+export type Deck = z.infer<typeof Deck>;
+
+export const DeckTerm = z.object({
+  deck_id: z.uuid(),
+  term_id: z.uuid(),
+  added: z.iso.datetime(),
+});
+
+export type DeckTerm = z.infer<typeof DeckTerm>;
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 5ff559a..d4e4bc2 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -132,7 +132,11 @@ importers:
         specifier: ^0.31.10
         version: 0.31.10
 
-  packages/shared: {}
+  packages/shared:
+    dependencies:
+      zod:
+        specifier: ^4.3.6
+        version: 4.3.6
 
 packages: