TryGhost · rob-ghost · Jun 23, 2026
diff --git a/ghost/core/core/server/services/gift-links/case-keys.ts b/ghost/core/core/server/services/gift-links/case-keys.ts
@@ -0,0 +1,30 @@
+// Flat snake_case <-> camelCase key mappers. Top-level keys only: values are copied by reference
+// and their types pass through untouched (T[K]). Deep case-convert libraries recurse into value
+// types, which mangles branded primitives (a branded string is `string & {...}`, so it reads as an
+// object and gets walked); staying flat sidesteps that and keeps the keys' value types exact.
+
+type SnakeToCamel<S extends string> = S extends `${infer Head}_${infer Tail}`
+    ? `${Head}${Capitalize<SnakeToCamel<Tail>>}`
+    : S;
+
+type CamelToSnake<S extends string> = S extends `${infer Head}${infer Tail}`
+    ? Head extends Uppercase<Head>
+        ? Head extends Lowercase<Head>
+            ? `${Head}${CamelToSnake<Tail>}` // non-letter (digit, etc.): leave as-is
+            : `_${Lowercase<Head>}${CamelToSnake<Tail>}` // uppercase letter: split with an underscore
+        : `${Head}${CamelToSnake<Tail>}` // lowercase letter: keep
+    : S;
+
+export type CamelKeys<T> = {[K in keyof T as SnakeToCamel<K & string>]: T[K]};
+export type SnakeKeys<T> = {[K in keyof T as CamelToSnake<K & string>]: T[K]};
+
+const toCamel = (key: string): string => key.replace(/_([a-z])/g, (_full, letter: string) => letter.toUpperCase());
+const toSnake = (key: string): string => key.replace(/[A-Z]/g, letter => `_${letter.toLowerCase()}`);
+
+export function camelKeys<T extends object>(row: T): CamelKeys<T> {
+    return Object.fromEntries(Object.entries(row).map(([key, value]) => [toCamel(key), value])) as CamelKeys<T>;
+}
+
+export function snakeKeys<T extends object>(model: T): SnakeKeys<T> {
+    return Object.fromEntries(Object.entries(model).map(([key, value]) => [toSnake(key), value])) as SnakeKeys<T>;
+}
diff --git a/ghost/core/core/server/services/gift-links/queries.ts b/ghost/core/core/server/services/gift-links/queries.ts
@@ -1,5 +1,6 @@
 import {z} from 'zod';
 import type {Knex} from 'knex';
+import {camelKeys, snakeKeys} from './case-keys';
 import {DbGiftLink} from './database';
 import {GiftLink} from './models';
 
@@ -13,18 +14,8 @@ export const GiftLinkRow = DbGiftLink.pick({
 
 // Maps a selected row to/from the domain GiftLink (snake_case to camelCase, token branding).
 export const giftLinkCodec = z.codec(GiftLinkRow, GiftLink, {
-    decode: row => ({
-        token: row.token,
-        redeemedCount: row.redeemed_count,
-        lastRedeemedAt: row.last_redeemed_at,
-        createdAt: row.created_at
-    }),
-    encode: link => ({
-        token: link.token,
-        redeemed_count: link.redeemedCount,
-        last_redeemed_at: link.lastRedeemedAt,
-        created_at: link.createdAt
-    })
+    decode: row => camelKeys(row),
+    encode: link => snakeKeys(link)
 });
 
 const giftLinkColumns = Object.keys(GiftLinkRow.shape).map(column => `gift_links.${column}`);

diff --git a/ghost/core/core/server/services/gift-links/serializers.ts b/ghost/core/core/server/services/gift-links/serializers.ts
@@ -1,4 +1,5 @@
 import {z} from 'zod';
+import {snakeKeys} from './case-keys';
 import {GiftLink} from './models';
 import type {Post} from './models';
 
@@ -18,12 +19,7 @@ const RevokeAllResponse = z.object({meta: z.object({count: z.number()})});
 
 const toGiftLinksResponse = z.array(GiftLink)
     .transform((links): z.input<typeof GiftLinksResponse> => ({
-        gift_links: links.map(link => ({
-            token: link.token,
-            redeemed_count: link.redeemedCount,
-            last_redeemed_at: link.lastRedeemedAt,
-            created_at: link.createdAt
-        }))
+        gift_links: links.map(link => snakeKeys(link))
     }))
     .pipe(GiftLinksResponse);