diff --git a/backend/jest.config.js b/backend/jest.config.js
new file mode 100644
index 0000000..9862749
--- /dev/null
+++ b/backend/jest.config.js
@@ -0,0 +1,18 @@
+/** @type {import('ts-jest').JestConfigWithTsJest} */
+module.exports = {
+  preset: 'ts-jest',
+  testEnvironment: 'node',
+  roots: ['<rootDir>/src'],
+  testMatch: [
+    '**/__tests__/**/*.+(ts|tsx|js)',
+    '**/?(*.)+(spec|test).+(ts|tsx|js)'
+  ],
+  transform: {
+    '^.+\.(ts|tsx)$': 'ts-jest',
+  },
+  collectCoverageFrom: [
+    'src/**/*.{js,ts}',
+    '!src/server.ts',
+    '!src/**/*.d.ts'
+  ],
+};
\ No newline at end of file
diff --git a/backend/package-lock.json b/backend/package-lock.json
index 953e077..a4ea829 100644
--- a/backend/package-lock.json
+++ b/backend/package-lock.json
@@ -21,6 +21,7 @@
         "@types/bcryptjs": "^2.4.2",
         "@types/cors": "^2.8.13",
         "@types/express": "^4.17.17",
+        "@types/jest": "^29.5.0",
         "@types/jsonwebtoken": "^9.0.2",
         "@types/uuid": "^9.0.2",
         "ts-node": "^10.9.0",
@@ -28,6 +29,31 @@
         "typescript": "^5.0.0"
       }
     },
+    "node_modules/@babel/code-frame": {
+      "version": "7.27.1",
+      "resolved": "https://registry.npmjs.org/@babel/code-frame/-/code-frame-7.27.1.tgz",
+      "integrity": "sha512-cjQ7ZlQ0Mv3b47hABuTevyTuYN4i+loJKGeV9flcCgIK37cCXRh+L1bd3iBHlynerhQ7BhCkn2BPbQUL+rGqFg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@babel/helper-validator-identifier": "^7.27.1",
+        "js-tokens": "^4.0.0",
+        "picocolors": "^1.1.1"
+      },
+      "engines": {
+        "node": ">=6.9.0"
+      }
+    },
+    "node_modules/@babel/helper-validator-identifier": {
+      "version": "7.27.1",
+      "resolved": "https://registry.npmjs.org/@babel/helper-validator-identifier/-/helper-validator-identifier-7.27.1.tgz",
+      "integrity": "sha512-D2hP9eA+Sqx1kBZgzxZh0y1trbuU+JoDkiEwqhQ36nodYqJwyEIhPSdMNd7lOm/4io72luTPWH20Yda0xOuUow==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">=6.9.0"
+      }
+    },
     "node_modules/@cspotcode/source-map-support": {
       "version": "0.8.1",
       "resolved": "https://registry.npmjs.org/@cspotcode/source-map-support/-/source-map-support-0.8.1.tgz",
@@ -490,6 +516,50 @@
       "license": "MIT",
       "optional": true
     },
+    "node_modules/@jest/expect-utils": {
+      "version": "29.7.0",
+      "resolved": "https://registry.npmjs.org/@jest/expect-utils/-/expect-utils-29.7.0.tgz",
+      "integrity": "sha512-GlsNBWiFQFCVi9QVSx7f5AgMeLxe9YCCs5PuP2O2LdjDAA8Jh9eX7lA1Jq/xdXw3Wb3hyvlFNfZIfcRetSzYcA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "jest-get-type": "^29.6.3"
+      },
+      "engines": {
+        "node": "^14.15.0 || ^16.10.0 || >=18.0.0"
+      }
+    },
+    "node_modules/@jest/schemas": {
+      "version": "29.6.3",
+      "resolved": "https://registry.npmjs.org/@jest/schemas/-/schemas-29.6.3.tgz",
+      "integrity": "sha512-mo5j5X+jIZmJQveBKeS/clAueipV7KgiX1vMgCxam1RNYiqE1w62n0/tJJnHtjW8ZHcQco5gY85jA3mi0L+nSA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@sinclair/typebox": "^0.27.8"
+      },
+      "engines": {
+        "node": "^14.15.0 || ^16.10.0 || >=18.0.0"
+      }
+    },
+    "node_modules/@jest/types": {
+      "version": "29.6.3",
+      "resolved": "https://registry.npmjs.org/@jest/types/-/types-29.6.3.tgz",
+      "integrity": "sha512-u3UPsIilWKOM3F9CXtrG8LEJmNxwoCQC/XVj4IKYXvvpx7QIi/Kg1LI5uDmDpKlac62NUtX7eLjRh+jVZcLOzw==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@jest/schemas": "^29.6.3",
+        "@types/istanbul-lib-coverage": "^2.0.0",
+        "@types/istanbul-reports": "^3.0.0",
+        "@types/node": "*",
+        "@types/yargs": "^17.0.8",
+        "chalk": "^4.0.0"
+      },
+      "engines": {
+        "node": "^14.15.0 || ^16.10.0 || >=18.0.0"
+      }
+    },
     "node_modules/@jridgewell/resolve-uri": {
       "version": "3.1.2",
       "resolved": "https://registry.npmjs.org/@jridgewell/resolve-uri/-/resolve-uri-3.1.2.tgz",
@@ -544,6 +614,13 @@
         "node": ">=10"
       }
     },
+    "node_modules/@sinclair/typebox": {
+      "version": "0.27.8",
+      "resolved": "https://registry.npmjs.org/@sinclair/typebox/-/typebox-0.27.8.tgz",
+      "integrity": "sha512-+Fj43pSMwJs4KRrH/938Uf+uAELIgVBmQzg/q1YG10djyfA3TnrU8N8XzqCh/okZdszqBQTZf96idMfE5lnwTA==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/@tootallnate/once": {
       "version": "1.1.2",
       "resolved": "https://registry.npmjs.org/@tootallnate/once/-/once-1.1.2.tgz",
@@ -662,6 +739,44 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/@types/istanbul-lib-coverage": {
+      "version": "2.0.6",
+      "resolved": "https://registry.npmjs.org/@types/istanbul-lib-coverage/-/istanbul-lib-coverage-2.0.6.tgz",
+      "integrity": "sha512-2QF/t/auWm0lsy8XtKVPG19v3sSOQlJe/YHZgfjb/KBBHOGSV+J2q/S671rcq9uTBrLAXmZpqJiaQbMT+zNU1w==",
+      "dev": true,
+      "license": "MIT"
+    },
+    "node_modules/@types/istanbul-lib-report": {
+      "version": "3.0.3",
+      "resolved": "https://registry.npmjs.org/@types/istanbul-lib-report/-/istanbul-lib-report-3.0.3.tgz",
+      "integrity": "sha512-NQn7AHQnk/RSLOxrBbGyJM/aVQ+pjj5HCgasFxc0K/KhoATfQ/47AyUl15I2yBUpihjmas+a+VJBOqecrFH+uA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@types/istanbul-lib-coverage": "*"
+      }
+    },
+    "node_modules/@types/istanbul-reports": {
+      "version": "3.0.4",
+      "resolved": "https://registry.npmjs.org/@types/istanbul-reports/-/istanbul-reports-3.0.4.tgz",
+      "integrity": "sha512-pk2B1NWalF9toCRu6gjBzR69syFjP4Od8WRAX+0mmf9lAjCRicLOWc+ZrxZHx/0XRjotgkF9t6iaMJ+aXcOdZQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@types/istanbul-lib-report": "*"
+      }
+    },
+    "node_modules/@types/jest": {
+      "version": "29.5.14",
+      "resolved": "https://registry.npmjs.org/@types/jest/-/jest-29.5.14.tgz",
+      "integrity": "sha512-ZN+4sdnLUbo8EVvVc2ao0GFW6oVrQRPn4K2lglySj7APvSrgzxHiNNK99us4WDMi57xxA2yggblIAMNhXOotLQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "expect": "^29.0.0",
+        "pretty-format": "^29.0.0"
+      }
+    },
     "node_modules/@types/jsonwebtoken": {
       "version": "9.0.10",
       "resolved": "https://registry.npmjs.org/@types/jsonwebtoken/-/jsonwebtoken-9.0.10.tgz",
@@ -743,6 +858,13 @@
         "@types/node": "*"
       }
     },
+    "node_modules/@types/stack-utils": {
+      "version": "2.0.3",
+      "resolved": "https://registry.npmjs.org/@types/stack-utils/-/stack-utils-2.0.3.tgz",
+      "integrity": "sha512-9aEbYZ3TbYMznPdcdr3SmIrLXwC/AKZXQeCf9Pgao5CKb8CyHuEX5jzWPTkvregvhRJHcpRO6BFoGW9ycaOkYw==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/@types/uuid": {
       "version": "9.0.8",
       "resolved": "https://registry.npmjs.org/@types/uuid/-/uuid-9.0.8.tgz",
@@ -750,6 +872,23 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/@types/yargs": {
+      "version": "17.0.33",
+      "resolved": "https://registry.npmjs.org/@types/yargs/-/yargs-17.0.33.tgz",
+      "integrity": "sha512-WpxBCKWPLr4xSsHgz511rFJAM+wS28w2zEO1QDNY5zM/S8ok70NNfztH0xwhqKyaK0OHCbN98LDAZuy1ctxDkA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@types/yargs-parser": "*"
+      }
+    },
+    "node_modules/@types/yargs-parser": {
+      "version": "21.0.3",
+      "resolved": "https://registry.npmjs.org/@types/yargs-parser/-/yargs-parser-21.0.3.tgz",
+      "integrity": "sha512-I4q9QU9MQv4oEOz4tAHJtNz1cwuLxn2F3xcc2iV5WdqLPpUnj30aUuxt1mAxYTG+oe8CZMV/+6rU4S4gRDzqtQ==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/abbrev": {
       "version": "1.1.1",
       "resolved": "https://registry.npmjs.org/abbrev/-/abbrev-1.1.1.tgz",
@@ -846,6 +985,22 @@
         "node": ">=8"
       }
     },
+    "node_modules/ansi-styles": {
+      "version": "4.3.0",
+      "resolved": "https://registry.npmjs.org/ansi-styles/-/ansi-styles-4.3.0.tgz",
+      "integrity": "sha512-zbB9rCJAT1rbjiVDb2hqKFHNYLxgtk8NURxZ3IZwD3F6NtxbXZQCnnSi1Lkx+IDohdPlFp222wVALIheZJQSEg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "color-convert": "^2.0.1"
+      },
+      "engines": {
+        "node": ">=8"
+      },
+      "funding": {
+        "url": "https://github.com/chalk/ansi-styles?sponsor=1"
+      }
+    },
     "node_modules/aproba": {
       "version": "2.1.0",
       "resolved": "https://registry.npmjs.org/aproba/-/aproba-2.1.0.tgz",
@@ -1019,6 +1174,19 @@
         "concat-map": "0.0.1"
       }
     },
+    "node_modules/braces": {
+      "version": "3.0.3",
+      "resolved": "https://registry.npmjs.org/braces/-/braces-3.0.3.tgz",
+      "integrity": "sha512-yQbXgO/OSZVD2IsiLlro+7Hf6Q18EJrKSEsdoMzKePKXct3gvD8oLcOQdIzGupr5Fj+EDe8gO/lxc1BzfMpxvA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "fill-range": "^7.1.1"
+      },
+      "engines": {
+        "node": ">=8"
+      }
+    },
     "node_modules/buffer": {
       "version": "5.7.1",
       "resolved": "https://registry.npmjs.org/buffer/-/buffer-5.7.1.tgz",
@@ -1117,6 +1285,23 @@
         "url": "https://github.com/sponsors/ljharb"
       }
     },
+    "node_modules/chalk": {
+      "version": "4.1.2",
+      "resolved": "https://registry.npmjs.org/chalk/-/chalk-4.1.2.tgz",
+      "integrity": "sha512-oKnbhFyRIXpUuez8iBMmyEa4nbj4IOQyuhc/wy9kY7/WVPcwIO9VA668Pu8RkO7+0G76SLROeyw9CpQ061i4mA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "ansi-styles": "^4.1.0",
+        "supports-color": "^7.1.0"
+      },
+      "engines": {
+        "node": ">=10"
+      },
+      "funding": {
+        "url": "https://github.com/chalk/chalk?sponsor=1"
+      }
+    },
     "node_modules/chownr": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/chownr/-/chownr-2.0.0.tgz",
@@ -1126,6 +1311,22 @@
         "node": ">=10"
       }
     },
+    "node_modules/ci-info": {
+      "version": "3.9.0",
+      "resolved": "https://registry.npmjs.org/ci-info/-/ci-info-3.9.0.tgz",
+      "integrity": "sha512-NIxF55hv4nSqQswkAeiOi1r83xy8JldOFDTWiug55KBu9Jnblncd2U6ViHmYgHf01TPZS77NJBhBMKdWj9HQMQ==",
+      "dev": true,
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/sibiraj-s"
+        }
+      ],
+      "license": "MIT",
+      "engines": {
+        "node": ">=8"
+      }
+    },
     "node_modules/clean-stack": {
       "version": "2.2.0",
       "resolved": "https://registry.npmjs.org/clean-stack/-/clean-stack-2.2.0.tgz",
@@ -1136,6 +1337,26 @@
         "node": ">=6"
       }
     },
+    "node_modules/color-convert": {
+      "version": "2.0.1",
+      "resolved": "https://registry.npmjs.org/color-convert/-/color-convert-2.0.1.tgz",
+      "integrity": "sha512-RRECPsj7iu/xb5oKYcsFHSppFNnsj/52OVTRKb4zP5onXwVF3zVmmToNcOfGC+CRDpfK/U584fMg38ZHCaElKQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "color-name": "~1.1.4"
+      },
+      "engines": {
+        "node": ">=7.0.0"
+      }
+    },
+    "node_modules/color-name": {
+      "version": "1.1.4",
+      "resolved": "https://registry.npmjs.org/color-name/-/color-name-1.1.4.tgz",
+      "integrity": "sha512-dOy+3AuW3a2wNbZHIuMZpTcgjGuLU/uBL/ubcZF9OXbDo8ff4O8yVp5Bf0efS8uEoYo5q4Fx7dY9OgQGXgAsQA==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/color-support": {
       "version": "1.1.3",
       "resolved": "https://registry.npmjs.org/color-support/-/color-support-1.1.3.tgz",
@@ -1303,6 +1524,16 @@
         "node": ">=0.3.1"
       }
     },
+    "node_modules/diff-sequences": {
+      "version": "29.6.3",
+      "resolved": "https://registry.npmjs.org/diff-sequences/-/diff-sequences-29.6.3.tgz",
+      "integrity": "sha512-EjePK1srD3P08o2j4f0ExnylqRs5B9tJjcp9t1krH2qRi8CCdsYfwe9JgSLurFBWwq4uOlipzfk5fHNvwFKr8Q==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": "^14.15.0 || ^16.10.0 || >=18.0.0"
+      }
+    },
     "node_modules/dunder-proto": {
       "version": "1.0.1",
       "resolved": "https://registry.npmjs.org/dunder-proto/-/dunder-proto-1.0.1.tgz",
@@ -1462,6 +1693,16 @@
       "integrity": "sha512-NiSupZ4OeuGwr68lGIeym/ksIZMJodUGOSCZ/FSnTxcrekbvqrgdUxlJOMpijaKZVjAJrWrGs/6Jy8OMuyj9ow==",
       "license": "MIT"
     },
+    "node_modules/escape-string-regexp": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/escape-string-regexp/-/escape-string-regexp-2.0.0.tgz",
+      "integrity": "sha512-UpzcLCXolUWcNu5HtVMHYdXJjArjsF9C0aNnquZYY4uW/Vu0miy5YoWvbV345HauVvcAUnpRuhMMcqTcGOY2+w==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">=8"
+      }
+    },
     "node_modules/etag": {
       "version": "1.8.1",
       "resolved": "https://registry.npmjs.org/etag/-/etag-1.8.1.tgz",
@@ -1480,6 +1721,23 @@
         "node": ">=6"
       }
     },
+    "node_modules/expect": {
+      "version": "29.7.0",
+      "resolved": "https://registry.npmjs.org/expect/-/expect-29.7.0.tgz",
+      "integrity": "sha512-2Zks0hf1VLFYI1kbh0I5jP3KHHyCHpkfyHBzsSXRFgl/Bg9mWYfMW8oD+PdMPlEwy5HNsR9JutYy6pMeOh61nw==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@jest/expect-utils": "^29.7.0",
+        "jest-get-type": "^29.6.3",
+        "jest-matcher-utils": "^29.7.0",
+        "jest-message-util": "^29.7.0",
+        "jest-util": "^29.7.0"
+      },
+      "engines": {
+        "node": "^14.15.0 || ^16.10.0 || >=18.0.0"
+      }
+    },
     "node_modules/express": {
       "version": "4.21.2",
       "resolved": "https://registry.npmjs.org/express/-/express-4.21.2.tgz",
@@ -1547,6 +1805,19 @@
       "integrity": "sha512-0Zt+s3L7Vf1biwWZ29aARiVYLx7iMGnEUl9x33fbB/j3jR81u/O2LbqK+Bm1CDSNDKVtJ/YjwY7TUd5SkeLQLw==",
       "license": "MIT"
     },
+    "node_modules/fill-range": {
+      "version": "7.1.1",
+      "resolved": "https://registry.npmjs.org/fill-range/-/fill-range-7.1.1.tgz",
+      "integrity": "sha512-YsGpe3WHLK8ZYi4tWDg2Jy3ebRz2rXowDxnld4bkQB00cc/1Zw9AWnC0i9ztDJitivtQvaI9KaLyKrc+hBW0yg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "to-regex-range": "^5.0.1"
+      },
+      "engines": {
+        "node": ">=8"
+      }
+    },
     "node_modules/finalhandler": {
       "version": "1.3.1",
       "resolved": "https://registry.npmjs.org/finalhandler/-/finalhandler-1.3.1.tgz",
@@ -1762,8 +2033,18 @@
       "version": "4.2.11",
       "resolved": "https://registry.npmjs.org/graceful-fs/-/graceful-fs-4.2.11.tgz",
       "integrity": "sha512-RbJ5/jmFcNNCcDV5o9eTnBLJ/HszWV0P73bc+Ff4nS/rJj+YaS6IGyiOL0VoBYX+l1Wrl3k63h/KrH+nhJ0XvQ==",
-      "license": "ISC",
-      "optional": true
+      "devOptional": true,
+      "license": "ISC"
+    },
+    "node_modules/has-flag": {
+      "version": "4.0.0",
+      "resolved": "https://registry.npmjs.org/has-flag/-/has-flag-4.0.0.tgz",
+      "integrity": "sha512-EykJT/Q1KjTWctppgIAgfSO0tKVuZUjhgMr17kqTumMl6Afv3EISleU7qZUzoXDFTAHTDC4NOoG/ZxU3EvlMPQ==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">=8"
+      }
     },
     "node_modules/has-symbols": {
       "version": "1.1.0",
@@ -1978,6 +2259,16 @@
       "license": "MIT",
       "optional": true
     },
+    "node_modules/is-number": {
+      "version": "7.0.0",
+      "resolved": "https://registry.npmjs.org/is-number/-/is-number-7.0.0.tgz",
+      "integrity": "sha512-41Cifkg6e8TylSpdtTpeLVMqvSBEVzTttHvERD741+pnZ8ANv0004MRL43QKPDlK9cGvNp6NZWZUBlbGXYxxng==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">=0.12.0"
+      }
+    },
     "node_modules/isexe": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/isexe/-/isexe-2.0.0.tgz",
@@ -1985,6 +2276,94 @@
       "license": "ISC",
       "optional": true
     },
+    "node_modules/jest-diff": {
+      "version": "29.7.0",
+      "resolved": "https://registry.npmjs.org/jest-diff/-/jest-diff-29.7.0.tgz",
+      "integrity": "sha512-LMIgiIrhigmPrs03JHpxUh2yISK3vLFPkAodPeo0+BuF7wA2FoQbkEg1u8gBYBThncu7e1oEDUfIXVuTqLRUjw==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "chalk": "^4.0.0",
+        "diff-sequences": "^29.6.3",
+        "jest-get-type": "^29.6.3",
+        "pretty-format": "^29.7.0"
+      },
+      "engines": {
+        "node": "^14.15.0 || ^16.10.0 || >=18.0.0"
+      }
+    },
+    "node_modules/jest-get-type": {
+      "version": "29.6.3",
+      "resolved": "https://registry.npmjs.org/jest-get-type/-/jest-get-type-29.6.3.tgz",
+      "integrity": "sha512-zrteXnqYxfQh7l5FHyL38jL39di8H8rHoecLH3JNxH3BwOrBsNeabdap5e0I23lD4HHI8W5VFBZqG4Eaq5LNcw==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": "^14.15.0 || ^16.10.0 || >=18.0.0"
+      }
+    },
+    "node_modules/jest-matcher-utils": {
+      "version": "29.7.0",
+      "resolved": "https://registry.npmjs.org/jest-matcher-utils/-/jest-matcher-utils-29.7.0.tgz",
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+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "chalk": "^4.0.0",
+        "jest-diff": "^29.7.0",
+        "jest-get-type": "^29.6.3",
+        "pretty-format": "^29.7.0"
+      },
+      "engines": {
+        "node": "^14.15.0 || ^16.10.0 || >=18.0.0"
+      }
+    },
+    "node_modules/jest-message-util": {
+      "version": "29.7.0",
+      "resolved": "https://registry.npmjs.org/jest-message-util/-/jest-message-util-29.7.0.tgz",
+      "integrity": "sha512-GBEV4GRADeP+qtB2+6u61stea8mGcOT4mCtrYISZwfu9/ISHFJ/5zOMXYbpBE9RsS5+Gb63DW4FgmnKJ79Kf6w==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@babel/code-frame": "^7.12.13",
+        "@jest/types": "^29.6.3",
+        "@types/stack-utils": "^2.0.0",
+        "chalk": "^4.0.0",
+        "graceful-fs": "^4.2.9",
+        "micromatch": "^4.0.4",
+        "pretty-format": "^29.7.0",
+        "slash": "^3.0.0",
+        "stack-utils": "^2.0.3"
+      },
+      "engines": {
+        "node": "^14.15.0 || ^16.10.0 || >=18.0.0"
+      }
+    },
+    "node_modules/jest-util": {
+      "version": "29.7.0",
+      "resolved": "https://registry.npmjs.org/jest-util/-/jest-util-29.7.0.tgz",
+      "integrity": "sha512-z6EbKajIpqGKU56y5KBUgy1dt1ihhQJgWzUlZHArA/+X2ad7Cb5iF+AK1EWVL/Bo7Rz9uurpqw6SiBCefUbCGA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@jest/types": "^29.6.3",
+        "@types/node": "*",
+        "chalk": "^4.0.0",
+        "ci-info": "^3.2.0",
+        "graceful-fs": "^4.2.9",
+        "picomatch": "^2.2.3"
+      },
+      "engines": {
+        "node": "^14.15.0 || ^16.10.0 || >=18.0.0"
+      }
+    },
+    "node_modules/js-tokens": {
+      "version": "4.0.0",
+      "resolved": "https://registry.npmjs.org/js-tokens/-/js-tokens-4.0.0.tgz",
+      "integrity": "sha512-RdJUflcE3cUzKiMqQgsCu06FPu9UdIJO0beYbPhHN4k6apgJtifcoCtT9bcxOpYBtpD2kCM6Sbzg4CausW/PKQ==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/jsonwebtoken": {
       "version": "9.0.2",
       "resolved": "https://registry.npmjs.org/jsonwebtoken/-/jsonwebtoken-9.0.2.tgz",
@@ -2164,6 +2543,20 @@
         "node": ">= 0.6"
       }
     },
+    "node_modules/micromatch": {
+      "version": "4.0.8",
+      "resolved": "https://registry.npmjs.org/micromatch/-/micromatch-4.0.8.tgz",
+      "integrity": "sha512-PXwfBhYu0hBCPw8Dn0E+WDYb7af3dSLVWKi3HGv84IdF4TyFoC0ysxFd0Goxw7nSv4T/PzEJQxsYsEiFCKo2BA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "braces": "^3.0.3",
+        "picomatch": "^2.3.1"
+      },
+      "engines": {
+        "node": ">=8.6"
+      }
+    },
     "node_modules/mime": {
       "version": "1.6.0",
       "resolved": "https://registry.npmjs.org/mime/-/mime-1.6.0.tgz",
@@ -2535,6 +2928,26 @@
       "integrity": "sha512-RA1GjUVMnvYFxuqovrEqZoxxW5NUZqbwKtYz/Tt7nXerk0LbLblQmrsgdeOxV5SFHf0UDggjS/bSeOZwt1pmEQ==",
       "license": "MIT"
     },
+    "node_modules/picocolors": {
+      "version": "1.1.1",
+      "resolved": "https://registry.npmjs.org/picocolors/-/picocolors-1.1.1.tgz",
+      "integrity": "sha512-xceH2snhtb5M9liqDsmEw56le376mTZkEX/jEb/RxNFyegNul7eNslCXP9FDj/Lcu0X8KEyMceP2ntpaHrDEVA==",
+      "dev": true,
+      "license": "ISC"
+    },
+    "node_modules/picomatch": {
+      "version": "2.3.1",
+      "resolved": "https://registry.npmjs.org/picomatch/-/picomatch-2.3.1.tgz",
+      "integrity": "sha512-JU3teHTNjmE2VCGFzuY8EXzCDVwEqB2a8fsIvwaStHhAWJEeVd1o1QD80CU6+ZdEXXSLbSsuLwJjkCBWqRQUVA==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">=8.6"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/jonschlinkert"
+      }
+    },
     "node_modules/prebuild-install": {
       "version": "7.1.3",
       "resolved": "https://registry.npmjs.org/prebuild-install/-/prebuild-install-7.1.3.tgz",
@@ -2561,6 +2974,34 @@
         "node": ">=10"
       }
     },
+    "node_modules/pretty-format": {
+      "version": "29.7.0",
+      "resolved": "https://registry.npmjs.org/pretty-format/-/pretty-format-29.7.0.tgz",
+      "integrity": "sha512-Pdlw/oPxN+aXdmM9R00JVC9WVFoCLTKJvDVLgmJ+qAffBMxsV85l/Lu7sNx4zSzPyoL2euImuEwHhOXdEgNFZQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@jest/schemas": "^29.6.3",
+        "ansi-styles": "^5.0.0",
+        "react-is": "^18.0.0"
+      },
+      "engines": {
+        "node": "^14.15.0 || ^16.10.0 || >=18.0.0"
+      }
+    },
+    "node_modules/pretty-format/node_modules/ansi-styles": {
+      "version": "5.2.0",
+      "resolved": "https://registry.npmjs.org/ansi-styles/-/ansi-styles-5.2.0.tgz",
+      "integrity": "sha512-Cxwpt2SfTzTtXcfOlzGEee8O+c+MmUgGrNiBcXnuWxuFJHe6a5Hz7qwhwe5OgaSYI0IJvkLqWX1ASG+cJOkEiA==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">=10"
+      },
+      "funding": {
+        "url": "https://github.com/chalk/ansi-styles?sponsor=1"
+      }
+    },
     "node_modules/promise-inflight": {
       "version": "1.0.1",
       "resolved": "https://registry.npmjs.org/promise-inflight/-/promise-inflight-1.0.1.tgz",
@@ -2671,6 +3112,13 @@
         "rc": "cli.js"
       }
     },
+    "node_modules/react-is": {
+      "version": "18.3.1",
+      "resolved": "https://registry.npmjs.org/react-is/-/react-is-18.3.1.tgz",
+      "integrity": "sha512-/LLMVyas0ljjAtoYiPqYiL8VWXzUUdThrmU5+n20DZv+a+ClRoevUzw5JxU+Ieh5/c87ytoTBV9G1FiKfNJdmg==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/readable-stream": {
       "version": "3.6.2",
       "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-3.6.2.tgz",
@@ -2960,6 +3408,16 @@
         "simple-concat": "^1.0.0"
       }
     },
+    "node_modules/slash": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/slash/-/slash-3.0.0.tgz",
+      "integrity": "sha512-g9Q1haeby36OSStwb4ntCGGGaKsaVSjQ68fBxoQcutl5fS1vuY18H3wSt3jFyFtrkx+Kz0V1G85A4MyAdDMi2Q==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">=8"
+      }
+    },
     "node_modules/smart-buffer": {
       "version": "4.2.0",
       "resolved": "https://registry.npmjs.org/smart-buffer/-/smart-buffer-4.2.0.tgz",
@@ -3038,6 +3496,19 @@
         "node": ">= 8"
       }
     },
+    "node_modules/stack-utils": {
+      "version": "2.0.6",
+      "resolved": "https://registry.npmjs.org/stack-utils/-/stack-utils-2.0.6.tgz",
+      "integrity": "sha512-XlkWvfIm6RmsWtNJx+uqtKLS8eqFbxUg0ZzLXqY0caEy9l7hruX8IpiDnjsLavoBgqCCR71TqWO8MaXYheJ3RQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "escape-string-regexp": "^2.0.0"
+      },
+      "engines": {
+        "node": ">=10"
+      }
+    },
     "node_modules/statuses": {
       "version": "2.0.1",
       "resolved": "https://registry.npmjs.org/statuses/-/statuses-2.0.1.tgz",
@@ -3093,6 +3564,19 @@
         "node": ">=0.10.0"
       }
     },
+    "node_modules/supports-color": {
+      "version": "7.2.0",
+      "resolved": "https://registry.npmjs.org/supports-color/-/supports-color-7.2.0.tgz",
+      "integrity": "sha512-qpCAvRl9stuOHveKsn7HncJRvv501qIacKzQlO/+Lwxc9+0q2wLyv4Dfvt80/DPn2pqOBsJdDiogXGR9+OvwRw==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "has-flag": "^4.0.0"
+      },
+      "engines": {
+        "node": ">=8"
+      }
+    },
     "node_modules/tar": {
       "version": "6.2.1",
       "resolved": "https://registry.npmjs.org/tar/-/tar-6.2.1.tgz",
@@ -3153,6 +3637,19 @@
         "node": ">=8"
       }
     },
+    "node_modules/to-regex-range": {
+      "version": "5.0.1",
+      "resolved": "https://registry.npmjs.org/to-regex-range/-/to-regex-range-5.0.1.tgz",
+      "integrity": "sha512-65P7iz6X5yEr1cwcgvQxbbIw7Uk3gOy5dIdtZ4rDveLqhrdJP+Li/Hx6tyK0NEb+2GCyneCMJiGqrADCSNk8sQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "is-number": "^7.0.0"
+      },
+      "engines": {
+        "node": ">=8.0"
+      }
+    },
     "node_modules/toidentifier": {
       "version": "1.0.1",
       "resolved": "https://registry.npmjs.org/toidentifier/-/toidentifier-1.0.1.tgz",
diff --git a/backend/package.json b/backend/package.json
index 2e5695a..6b91829 100644
--- a/backend/package.json
+++ b/backend/package.json
@@ -8,7 +8,7 @@
     "start": "node dist/server.js",
     "prestart": "npm run build",
     "test": "jest",
-    "test:python": "python3 -c \"from ortools.sat.python import cp_model; print('OR-Tools OK')\"",
+    "test:python": "python -c \"from ortools.sat.python import cp_model; print('OR-Tools OK')\"",
     "docker:build": "docker build -t schichtplan-backend .",
     "docker:run": "docker run -p 3001:3001 schichtplan-backend"
   },
@@ -28,6 +28,7 @@
     "@types/express": "^4.17.17",
     "@types/jsonwebtoken": "^9.0.2",
     "@types/uuid": "^9.0.2",
+    "@types/jest": "^29.5.0",
     "ts-node": "^10.9.0",
     "typescript": "^5.0.0",
     "tsx": "^4.0.0"