diff --git a/bun.lock b/bun.lock
index 642fcde..b9484d7 100644
--- a/bun.lock
+++ b/bun.lock
@@ -26,7 +26,7 @@
     },
     "app": {
       "name": "bknd",
-      "version": "0.13.1-rc.0",
+      "version": "0.14.0-rc.0",
       "bin": "./dist/cli/index.js",
       "dependencies": {
         "@cfworker/json-schema": "^4.1.1",
@@ -45,6 +45,7 @@
         "bcryptjs": "^3.0.2",
         "dayjs": "^1.11.13",
         "fast-xml-parser": "^5.0.8",
+        "hono": "^4.7.11",
         "json-schema-form-react": "^0.0.2",
         "json-schema-library": "10.0.0-rc7",
         "json-schema-to-ts": "^3.1.1",
@@ -82,7 +83,6 @@
         "autoprefixer": "^10.4.21",
         "clsx": "^2.1.1",
         "dotenv": "^16.4.7",
-        "hono": "4.7.11",
         "jotai": "^2.12.2",
         "jsdom": "^26.0.0",
         "jsonv-ts": "^0.1.0",
diff --git a/packages/postgres/src/PostgresConnection.ts b/packages/postgres/src/PostgresConnection.ts
index db219fd..9ea1d2c 100644
--- a/packages/postgres/src/PostgresConnection.ts
+++ b/packages/postgres/src/PostgresConnection.ts
@@ -32,7 +32,13 @@ export abstract class PostgresConnection<DB = any> extends Connection<DB> {
 
    override getFieldSchema(spec: FieldSpec): SchemaResponse {
       this.validateFieldSpecType(spec.type);
-      let type: ColumnDataType = spec.primary ? "serial" : spec.type;
+      let type: ColumnDataType = spec.type;
+
+      if (spec.primary) {
+         if (spec.type === "integer") {
+            type = "serial";
+         }
+      }
 
       switch (spec.type) {
          case "blob":
diff --git a/packages/postgres/test/suite.ts b/packages/postgres/test/suite.ts
index bf53337..0d4feec 100644
--- a/packages/postgres/test/suite.ts
+++ b/packages/postgres/test/suite.ts
@@ -151,5 +151,47 @@ export function testSuite(config: TestSuiteConfig) {
          expect(result[0].comments[0].content).toBe("Hello");
          expect(result[1].comments.length).toBe(0);
       });
+
+      it("should support uuid", async () => {
+         const schema = proto.em(
+            {
+               posts: proto.entity(
+                  "posts",
+                  {
+                     title: proto.text().required(),
+                     content: proto.text(),
+                  },
+                  {
+                     primary_format: "uuid",
+                  },
+               ),
+               comments: proto.entity("comments", {
+                  content: proto.text(),
+               }),
+            },
+            (fns, s) => {
+               fns.relation(s.comments).manyToOne(s.posts);
+               fns.index(s.posts).on(["title"], true);
+            },
+         );
+
+         const app = createApp({
+            connection,
+            initialConfig: {
+               data: schema.toJSON(),
+            },
+         });
+
+         await app.build();
+         const config = app.toJSON();
+         // @ts-expect-error
+         expect(config.data.entities?.posts.fields?.id.config?.format).toBe("uuid");
+
+         const em = app.em;
+         const mutator = em.mutator(em.entity("posts"));
+         const data = await mutator.insertOne({ title: "Hello", content: "World" });
+         expect(data.data.id).toBeString();
+         expect(String(data.data.id).length).toBe(36);
+      });
    });
 }