diff --git a/app/controllers/matrix.js b/app/controllers/matrix.ts
similarity index 54%
rename from app/controllers/matrix.js
rename to app/controllers/matrix.ts
index 225b061..3d0944b 100644
--- a/app/controllers/matrix.js
+++ b/app/controllers/matrix.ts
@@ -1,5 +1,11 @@
-const calcDeterminant = (req, res) => {
-  const matrix = JSON.parse(req.query.matrix)
+import { VercelRequest, VercelResponse } from "@vercel/node"
+
+const calcDeterminant = (req: VercelRequest, res: VercelResponse) => {
+  let matrix
+  // string array
+  if (Array.isArray(req.query.matrix))
+    matrix = JSON.parse(req.query.matrix.join())
+  else matrix = JSON.parse(req.query.matrix)
 
   const rows = matrix.length
   const cols = matrix[0].length
@@ -18,4 +24,6 @@ const calcDeterminant = (req, res) => {
   }
 }
 
-module.exports = { calcDeterminant }
+export default {
+  calcDeterminant,
+}
diff --git a/app/controllers/test.js b/app/controllers/test.js
deleted file mode 100644
index aa65941..0000000
--- a/app/controllers/test.js
+++ /dev/null
@@ -1,5 +0,0 @@
-const test = (req, res) => {
-  res.send("API call successful")
-}
-
-module.exports = { test }
diff --git a/app/controllers/test.ts b/app/controllers/test.ts
new file mode 100644
index 0000000..7048dcb
--- /dev/null
+++ b/app/controllers/test.ts
@@ -0,0 +1,9 @@
+import { VercelRequest, VercelResponse } from "@vercel/node"
+
+const test = (req: VercelRequest, res: VercelResponse) => {
+  res.send("API call successful")
+}
+
+export default {
+  test,
+}
diff --git a/app/tests/index.js b/app/tests/index.ts
similarity index 77%
rename from app/tests/index.js
rename to app/tests/index.ts
index 7d832db..b42f2d8 100644
--- a/app/tests/index.js
+++ b/app/tests/index.ts
@@ -1,17 +1,20 @@
 // standard testing modules
-const chai = require("chai")
-const chaiHttp = require("chai-http")
+import chai from "chai"
+import chaiHttp from "chai-http"
 
 // modules that help testing serverless functions
-const { createServer } = require("vercel-node-server")
-const listen = require("test-listen")
+import { createServer } from "vercel-node-server"
+import listen from "test-listen"
+
+// types
+import { Server } from "http"
 
 // import methods to be tested
-const Test = require("../controllers/test")
-const Matrix = require("../controllers/matrix")
+import Test from "../controllers/test"
+import Matrix from "../controllers/matrix"
 
 // beforeEach management
-let route, method, server, url
+let route: string, method, server: Server, url: string
 
 let testIndex = 0
 const toTest = [
@@ -52,7 +55,7 @@ describe("API tests", () => {
         .request(url)
         .get(route)
         .then((res) => {
-          chai.expect(res.statusCode).to.equal(200)
+          chai.expect(res.status).to.equal(200)
           chai.expect(res.text).to.equal("API call successful")
         })
     })
@@ -70,7 +73,7 @@ describe("API tests", () => {
           matrix: "[[1,2],[3,4]]",
         })
         .then((res) => {
-          chai.expect(res.statusCode).to.equal(200)
+          chai.expect(res.status).to.equal(200)
           chai.expect(res.body).to.equal(-2)
         })
     })
@@ -82,7 +85,7 @@ describe("API tests", () => {
           matrix: "[[1,2,3],[4,5,6],[7,8,9]]",
         })
         .then((res) => {
-          chai.expect(res.statusCode).to.equal(500)
+          chai.expect(res.status).to.equal(500)
           chai.expect(res.body.message).to.equal("Unsupported")
         })
     })
diff --git a/next-env.d.ts b/next-env.d.ts
new file mode 100644
index 0000000..c6643fd
--- /dev/null
+++ b/next-env.d.ts
@@ -0,0 +1,3 @@
+/// <reference types="next" />
+/// <reference types="next/types/global" />
+/// <reference types="next/image-types/global" />
diff --git a/package-lock.json b/package-lock.json
index 2dd9ca2..04b0abd 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -18,15 +18,21 @@
         "react": "^17.0.2",
         "react-dom": "^17.0.2",
         "test-listen": "^1.1.0",
+        "typescript": "^3.9.3",
         "vercel-node-server": "^2.2.1"
       },
       "devDependencies": {
         "@commitlint/cli": "^13.1.0",
         "@commitlint/config-conventional": "^13.1.0",
+        "@types/mocha": "^9.0.0",
+        "@types/react": "^17.0.15",
+        "@types/test-listen": "^1.1.0",
+        "@vercel/node": "^1.11.1",
         "chai": "^4.3.4",
         "chai-http": "^4.3.0",
         "husky": "^7.0.1",
-        "mocha": "^9.0.3"
+        "mocha": "^9.0.3",
+        "ts-node": "^8.9.1"
       }
     },
     "node_modules/@babel/code-frame": {
@@ -2410,6 +2416,12 @@
       "integrity": "sha512-jhuKLIRrhvCPLqwPcx6INqmKeiA5EWrsCOPhrlFSrbrmU4ZMPjj5Ul/oLCMDO98XRUIwVm78xICz4EPCektzeQ==",
       "dev": true
     },
+    "node_modules/@types/mocha": {
+      "version": "9.0.0",
+      "resolved": "https://registry.npmjs.org/@types/mocha/-/mocha-9.0.0.tgz",
+      "integrity": "sha512-scN0hAWyLVAvLR9AyW7HoFF5sJZglyBsbPuHO4fv7JRvfmPBMfp1ozWqOf/e4wwPNxezBZXRfWzMb6iFLgEVRA==",
+      "dev": true
+    },
     "node_modules/@types/node": {
       "version": "16.4.2",
       "resolved": "https://registry.npmjs.org/@types/node/-/node-16.4.2.tgz",
@@ -2426,6 +2438,29 @@
       "resolved": "https://registry.npmjs.org/@types/parse-json/-/parse-json-4.0.0.tgz",
       "integrity": "sha512-//oorEZjL6sbPcKUaCdIGlIUeH26mgzimjBB77G6XRgnDl/L5wOnpyBGRe/Mmf5CVW3PwEBE1NjiMZ/ssFh4wA=="
     },
+    "node_modules/@types/prop-types": {
+      "version": "15.7.4",
+      "resolved": "https://registry.npmjs.org/@types/prop-types/-/prop-types-15.7.4.tgz",
+      "integrity": "sha512-rZ5drC/jWjrArrS8BR6SIr4cWpW09RNTYt9AMZo3Jwwif+iacXAqgVjm0B0Bv/S1jhDXKHqRVNCbACkJ89RAnQ==",
+      "devOptional": true
+    },
+    "node_modules/@types/react": {
+      "version": "17.0.15",
+      "resolved": "https://registry.npmjs.org/@types/react/-/react-17.0.15.tgz",
+      "integrity": "sha512-uTKHDK9STXFHLaKv6IMnwp52fm0hwU+N89w/p9grdUqcFA6WuqDyPhaWopbNyE1k/VhgzmHl8pu1L4wITtmlLw==",
+      "devOptional": true,
+      "dependencies": {
+        "@types/prop-types": "*",
+        "@types/scheduler": "*",
+        "csstype": "^3.0.2"
+      }
+    },
+    "node_modules/@types/scheduler": {
+      "version": "0.16.2",
+      "resolved": "https://registry.npmjs.org/@types/scheduler/-/scheduler-0.16.2.tgz",
+      "integrity": "sha512-hppQEBDmlwhFAXKJX2KnWLYu5yMfi91yazPb2l+lbJiwW+wdo1gNeRA+3RgNSO39WYX2euey41KEwnqesU2Jew==",
+      "devOptional": true
+    },
     "node_modules/@types/superagent": {
       "version": "3.8.7",
       "resolved": "https://registry.npmjs.org/@types/superagent/-/superagent-3.8.7.tgz",
@@ -2436,6 +2471,15 @@
         "@types/node": "*"
       }
     },
+    "node_modules/@types/test-listen": {
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/@types/test-listen/-/test-listen-1.1.0.tgz",
+      "integrity": "sha512-y6ZfbSzYHniCeY6ZAzsQjSAdJInNVoEz4Uhsb81W+RCoNYA59yoG/+XbqPqCPj2KCU3Wa6RFWSozutkGIHIsNQ==",
+      "dev": true,
+      "dependencies": {
+        "@types/node": "*"
+      }
+    },
     "node_modules/@types/tinycolor2": {
       "version": "1.4.2",
       "resolved": "https://registry.npmjs.org/@types/tinycolor2/-/tinycolor2-1.4.2.tgz",
@@ -9810,6 +9854,12 @@
       "integrity": "sha512-jhuKLIRrhvCPLqwPcx6INqmKeiA5EWrsCOPhrlFSrbrmU4ZMPjj5Ul/oLCMDO98XRUIwVm78xICz4EPCektzeQ==",
       "dev": true
     },
+    "@types/mocha": {
+      "version": "9.0.0",
+      "resolved": "https://registry.npmjs.org/@types/mocha/-/mocha-9.0.0.tgz",
+      "integrity": "sha512-scN0hAWyLVAvLR9AyW7HoFF5sJZglyBsbPuHO4fv7JRvfmPBMfp1ozWqOf/e4wwPNxezBZXRfWzMb6iFLgEVRA==",
+      "dev": true
+    },
     "@types/node": {
       "version": "16.4.2",
       "resolved": "https://registry.npmjs.org/@types/node/-/node-16.4.2.tgz",
@@ -9826,6 +9876,29 @@
       "resolved": "https://registry.npmjs.org/@types/parse-json/-/parse-json-4.0.0.tgz",
       "integrity": "sha512-//oorEZjL6sbPcKUaCdIGlIUeH26mgzimjBB77G6XRgnDl/L5wOnpyBGRe/Mmf5CVW3PwEBE1NjiMZ/ssFh4wA=="
     },
+    "@types/prop-types": {
+      "version": "15.7.4",
+      "resolved": "https://registry.npmjs.org/@types/prop-types/-/prop-types-15.7.4.tgz",
+      "integrity": "sha512-rZ5drC/jWjrArrS8BR6SIr4cWpW09RNTYt9AMZo3Jwwif+iacXAqgVjm0B0Bv/S1jhDXKHqRVNCbACkJ89RAnQ==",
+      "devOptional": true
+    },
+    "@types/react": {
+      "version": "17.0.15",
+      "resolved": "https://registry.npmjs.org/@types/react/-/react-17.0.15.tgz",
+      "integrity": "sha512-uTKHDK9STXFHLaKv6IMnwp52fm0hwU+N89w/p9grdUqcFA6WuqDyPhaWopbNyE1k/VhgzmHl8pu1L4wITtmlLw==",
+      "devOptional": true,
+      "requires": {
+        "@types/prop-types": "*",
+        "@types/scheduler": "*",
+        "csstype": "^3.0.2"
+      }
+    },
+    "@types/scheduler": {
+      "version": "0.16.2",
+      "resolved": "https://registry.npmjs.org/@types/scheduler/-/scheduler-0.16.2.tgz",
+      "integrity": "sha512-hppQEBDmlwhFAXKJX2KnWLYu5yMfi91yazPb2l+lbJiwW+wdo1gNeRA+3RgNSO39WYX2euey41KEwnqesU2Jew==",
+      "devOptional": true
+    },
     "@types/superagent": {
       "version": "3.8.7",
       "resolved": "https://registry.npmjs.org/@types/superagent/-/superagent-3.8.7.tgz",
@@ -9836,6 +9909,15 @@
         "@types/node": "*"
       }
     },
+    "@types/test-listen": {
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/@types/test-listen/-/test-listen-1.1.0.tgz",
+      "integrity": "sha512-y6ZfbSzYHniCeY6ZAzsQjSAdJInNVoEz4Uhsb81W+RCoNYA59yoG/+XbqPqCPj2KCU3Wa6RFWSozutkGIHIsNQ==",
+      "dev": true,
+      "requires": {
+        "@types/node": "*"
+      }
+    },
     "@types/tinycolor2": {
       "version": "1.4.2",
       "resolved": "https://registry.npmjs.org/@types/tinycolor2/-/tinycolor2-1.4.2.tgz",
diff --git a/package.json b/package.json
index d93b6e8..c0ade40 100644
--- a/package.json
+++ b/package.json
@@ -8,7 +8,7 @@
     "build": "next build",
     "start": "next start",
     "version": "auto-changelog -p -l 0 && git add CHANGELOG.md",
-    "test": "mocha app/tests/index.js"
+    "test": "mocha -r ts-node/register app/tests/index.ts"
   },
   "repository": {
     "type": "git",
@@ -31,14 +31,20 @@
     "react": "^17.0.2",
     "react-dom": "^17.0.2",
     "test-listen": "^1.1.0",
+    "typescript": "^3.9.3",
     "vercel-node-server": "^2.2.1"
   },
   "devDependencies": {
     "@commitlint/cli": "^13.1.0",
     "@commitlint/config-conventional": "^13.1.0",
+    "@types/mocha": "^9.0.0",
+    "@types/react": "^17.0.15",
+    "@types/test-listen": "^1.1.0",
+    "@vercel/node": "^1.11.1",
     "chai": "^4.3.4",
     "chai-http": "^4.3.0",
     "husky": "^7.0.1",
-    "mocha": "^9.0.3"
+    "mocha": "^9.0.3",
+    "ts-node": "^8.9.1"
   }
 }
diff --git a/tsconfig.json b/tsconfig.json
new file mode 100644
index 0000000..3440dcb
--- /dev/null
+++ b/tsconfig.json
@@ -0,0 +1,22 @@
+{
+  "include": ["./app/**/*"],
+  "exclude": ["node_modules"],
+  "compilerOptions": {
+    "target": "es6",
+    "module": "commonjs",
+    "outDir": "./build",
+    "baseUrl": "./",
+    "esModuleInterop": true,
+    "allowJs": true,
+    "noImplicitAny": true,
+    "lib": ["dom", "dom.iterable", "esnext"],
+    "skipLibCheck": true,
+    "strict": false,
+    "forceConsistentCasingInFileNames": true,
+    "noEmit": true,
+    "moduleResolution": "node",
+    "resolveJsonModule": true,
+    "isolatedModules": true,
+    "jsx": "preserve"
+  }
+}