diff --git a/backend/jest.config.js b/backend/jest.config.js
index 6ab44002c..a472df316 100644
--- a/backend/jest.config.js
+++ b/backend/jest.config.js
@@ -5,6 +5,7 @@ module.exports = {
   collectCoverage: true,
   collectCoverageFrom: ['src/**/*.ts', '!**/node_modules/**', '!src/seeds/**', '!build/**'],
   setupFiles: ['<rootDir>/test/testSetup.ts'],
+  setupFilesAfterEnv: ['<rootDir>/test/extensions.ts'],
   modulePathIgnorePatterns: ['<rootDir>/build/'],
   moduleNameMapper: {
     '@/(.*)': '<rootDir>/src/$1',
diff --git a/backend/src/graphql/resolver/AdminResolver.test.ts b/backend/src/graphql/resolver/AdminResolver.test.ts
index 5c78e65e8..8d9e4bed0 100644
--- a/backend/src/graphql/resolver/AdminResolver.test.ts
+++ b/backend/src/graphql/resolver/AdminResolver.test.ts
@@ -1994,8 +1994,8 @@ describe('AdminResolver', () => {
                 deletedAt: null,
                 code: expect.stringMatching(/^[0-9a-f]{24,24}$/),
                 linkEnabled: true,
-                // amount: '200',
-                // maxAmountPerMonth: '200',
+                amount: expect.decimalEqual(200),
+                maxAmountPerMonth: expect.decimalEqual(200),
               }),
             )
           })
@@ -2284,7 +2284,7 @@ describe('AdminResolver', () => {
                   id: linkId,
                   name: 'Dokumenta 2023',
                   memo: 'Danke für deine Teilnahme an der Dokumenta 2023',
-                  // amount: '400',
+                  amount: expect.decimalEqual(400),
                 }),
               )
             })
diff --git a/backend/test/extensions.ts b/backend/test/extensions.ts
new file mode 100644
index 000000000..69c2ff7a6
--- /dev/null
+++ b/backend/test/extensions.ts
@@ -0,0 +1,33 @@
+/* eslint-disable @typescript-eslint/no-empty-interface */
+
+import Decimal from 'decimal.js-light'
+
+expect.extend({
+  decimalEqual(received, value) {
+    const pass = new Decimal(value).equals(received.toString())
+    if (pass) {
+      return {
+        message: () => `expected ${received} to not equal ${value}`,
+        pass: true,
+      }
+    } else {
+      return {
+        message: () => `expected ${received} to equal ${value}`,
+        pass: false,
+      }
+    }
+  },
+})
+
+interface CustomMatchers<R = unknown> {
+  decimalEqual(value: number): R
+}
+
+declare global {
+  // eslint-disable-next-line @typescript-eslint/no-namespace
+  namespace jest {
+    interface Expect extends CustomMatchers {}
+    interface Matchers<R> extends CustomMatchers<R> {}
+    interface InverseAsymmetricMatchers extends CustomMatchers {}
+  }
+}