Make function return types nullable

README.md

@@ -100,6 +100,8 @@ To start developing, run `npm run dev`. It will set up the database with Docker
 
 If you are fixing a bug, you should create a new test case. To test your changes, add the `-u/--updateSnapshot` flag to `jest` on the `test:run` script, run `npm run test`, and then review the git diff of the snapshots. Depending on your change, you may see `id` fields being changed - this is expected and you are free to commit it, as long as it passes the CI. Don't forget to remove the `-u/--updateSnapshot` flag when committing.
 
+To make changes to the TypeScript type generation, run `npm run gen:types:typescript` while you have `npm run dev` running.
+
 ## Licence
 
 Apache 2.0

src/server/templates/typescript.ts

@@ -90,7 +90,7 @@ export interface Database {
                               fn.return_type,
                               types,
                               schemas
-                            )}`
+                            )} | null`
                         ),
                     ]}
                   }