diff --git a/package-lock.json b/package-lock.json
index 11bfc83..4842d07 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,5 +1,261 @@
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diff --git a/package-lock.json b/package-lock.json
index 11bfc83..4842d07 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,5 +1,261 @@
 {
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 }
diff --git a/package.json b/package.json
index 18ea9f2..67f823a 100644
--- a/package.json
+++ b/package.json
@@ -1,12 +1,26 @@
 {
   "name": "labyrinth",
   "version": "0.1.0",
-  "description": "",
+  "description": "Labyrinth =========",
   "main": "app.js",
   "scripts": {
-    "test": "echo \"Error: no test specified\" && exit 1"
+    "test": "tsc && ./node_modules/mocha/bin/mocha dist/**/*.spec.js"
   },
   "author": "Peter Zilz",
   "license": "ISC",
-  "dependencies": {}
+  "dependencies": {},
+  "devDependencies": {
+    "@types/chai": "^4.1.6",
+    "@types/mocha": "^5.2.5",
+    "chai": "^4.2.0",
+    "mocha": "^5.2.0"
+  },
+  "repository": {
+    "type": "git",
+    "url": "http://git.synoikos.de/git/peter/Labyrinth.git"
+  },
+  "keywords": [
+    "TypeScript",
+    "game"
+  ]
 }

diff --git a/package-lock.json b/package-lock.json
index 11bfc83..4842d07 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,5 +1,261 @@
 {
   "name": "labyrinth",
   "version": "0.1.0",
-  "lockfileVersion": 1
+  "lockfileVersion": 1,
+  "requires": true,
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 }
diff --git a/package.json b/package.json
index 18ea9f2..67f823a 100644
--- a/package.json
+++ b/package.json
@@ -1,12 +1,26 @@
 {
   "name": "labyrinth",
   "version": "0.1.0",
-  "description": "",
+  "description": "Labyrinth =========",
   "main": "app.js",
   "scripts": {
-    "test": "echo \"Error: no test specified\" && exit 1"
+    "test": "tsc && ./node_modules/mocha/bin/mocha dist/**/*.spec.js"
   },
   "author": "Peter Zilz",
   "license": "ISC",
-  "dependencies": {}
+  "dependencies": {},
+  "devDependencies": {
+    "@types/chai": "^4.1.6",
+    "@types/mocha": "^5.2.5",
+    "chai": "^4.2.0",
+    "mocha": "^5.2.0"
+  },
+  "repository": {
+    "type": "git",
+    "url": "http://git.synoikos.de/git/peter/Labyrinth.git"
+  },
+  "keywords": [
+    "TypeScript",
+    "game"
+  ]
 }
diff --git a/src/NavigationEndpoint.spec.ts b/src/NavigationEndpoint.spec.ts
new file mode 100644
index 0000000..83588f1
--- /dev/null
+++ b/src/NavigationEndpoint.spec.ts
@@ -0,0 +1,68 @@
+// to get rid of "[ts] could not find module ..." in vs code realod the window: f1 -> type "reload window"
+// official issue for this: https://github.com/Microsoft/TypeScript/issues/10346
+
+import {expect} from "chai";
+import { Direction } from "./MazeMap";
+// import { describe, it } from "mocha";
+import {navigate, startGame} from "./NavigationEndpoint";
+
+describe("Scenario: Starting the game", function(){
+    describe("when the game is started", function(){
+        const position = startGame();
+
+        it("then the start position must exist", function(){
+            expect(position).to.be.not.null;
+        });
+
+        it("then the position must have at least one pathway", function(){
+            expect(position.paths.length).to.be.greaterThan(0);
+        });
+    });
+});
+
+describe("Scenario: Navigating in ongoing game", function(){
+    const startPosition = startGame();
+
+    describe("When player navigates in existing direction", function(){
+        const naviagtionDirection = startPosition.paths[0];
+        const nextPosition = navigate(startPosition.id, naviagtionDirection);
+        it("then the new position has to have a different id", function(){
+            expect(nextPosition.id).to.not.equal(startPosition.id);
+        });
+
+        it("then the new position must have pathway back", function(){
+            let hasOpposite:boolean = false;
+            for (const dir of nextPosition.paths) {
+                switch (dir) {
+                    case Direction.top:
+                        if(naviagtionDirection === Direction.bottom)
+                        {
+                            hasOpposite = true;
+                        }
+                        break;
+                    case Direction.left:
+                        if(naviagtionDirection === Direction.right)
+                        {
+                            hasOpposite = true;
+                        }
+                        break;
+                    case Direction.bottom:
+                        if(naviagtionDirection === Direction.top)
+                        {
+                            hasOpposite = true;
+                        }
+                        break;
+                    case Direction.right:
+                        if(naviagtionDirection === Direction.left)
+                        {
+                            hasOpposite = true;
+                        }
+                        break;
+                    default:
+                        throw new Error(`Direction "${dir}" not recognized.`);
+                }
+            }
+            expect(hasOpposite).to.be.true;
+        });
+    });
+});

diff --git a/package-lock.json b/package-lock.json
index 11bfc83..4842d07 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,5 +1,261 @@
 {
   "name": "labyrinth",
   "version": "0.1.0",
-  "lockfileVersion": 1
+  "lockfileVersion": 1,
+  "requires": true,
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 }
diff --git a/package.json b/package.json
index 18ea9f2..67f823a 100644
--- a/package.json
+++ b/package.json
@@ -1,12 +1,26 @@
 {
   "name": "labyrinth",
   "version": "0.1.0",
-  "description": "",
+  "description": "Labyrinth =========",
   "main": "app.js",
   "scripts": {
-    "test": "echo \"Error: no test specified\" && exit 1"
+    "test": "tsc && ./node_modules/mocha/bin/mocha dist/**/*.spec.js"
   },
   "author": "Peter Zilz",
   "license": "ISC",
-  "dependencies": {}
+  "dependencies": {},
+  "devDependencies": {
+    "@types/chai": "^4.1.6",
+    "@types/mocha": "^5.2.5",
+    "chai": "^4.2.0",
+    "mocha": "^5.2.0"
+  },
+  "repository": {
+    "type": "git",
+    "url": "http://git.synoikos.de/git/peter/Labyrinth.git"
+  },
+  "keywords": [
+    "TypeScript",
+    "game"
+  ]
 }
diff --git a/src/NavigationEndpoint.spec.ts b/src/NavigationEndpoint.spec.ts
new file mode 100644
index 0000000..83588f1
--- /dev/null
+++ b/src/NavigationEndpoint.spec.ts
@@ -0,0 +1,68 @@
+// to get rid of "[ts] could not find module ..." in vs code realod the window: f1 -> type "reload window"
+// official issue for this: https://github.com/Microsoft/TypeScript/issues/10346
+
+import {expect} from "chai";
+import { Direction } from "./MazeMap";
+// import { describe, it } from "mocha";
+import {navigate, startGame} from "./NavigationEndpoint";
+
+describe("Scenario: Starting the game", function(){
+    describe("when the game is started", function(){
+        const position = startGame();
+
+        it("then the start position must exist", function(){
+            expect(position).to.be.not.null;
+        });
+
+        it("then the position must have at least one pathway", function(){
+            expect(position.paths.length).to.be.greaterThan(0);
+        });
+    });
+});
+
+describe("Scenario: Navigating in ongoing game", function(){
+    const startPosition = startGame();
+
+    describe("When player navigates in existing direction", function(){
+        const naviagtionDirection = startPosition.paths[0];
+        const nextPosition = navigate(startPosition.id, naviagtionDirection);
+        it("then the new position has to have a different id", function(){
+            expect(nextPosition.id).to.not.equal(startPosition.id);
+        });
+
+        it("then the new position must have pathway back", function(){
+            let hasOpposite:boolean = false;
+            for (const dir of nextPosition.paths) {
+                switch (dir) {
+                    case Direction.top:
+                        if(naviagtionDirection === Direction.bottom)
+                        {
+                            hasOpposite = true;
+                        }
+                        break;
+                    case Direction.left:
+                        if(naviagtionDirection === Direction.right)
+                        {
+                            hasOpposite = true;
+                        }
+                        break;
+                    case Direction.bottom:
+                        if(naviagtionDirection === Direction.top)
+                        {
+                            hasOpposite = true;
+                        }
+                        break;
+                    case Direction.right:
+                        if(naviagtionDirection === Direction.left)
+                        {
+                            hasOpposite = true;
+                        }
+                        break;
+                    default:
+                        throw new Error(`Direction "${dir}" not recognized.`);
+                }
+            }
+            expect(hasOpposite).to.be.true;
+        });
+    });
+});
diff --git a/src/NavigationEndpoint.ts b/src/NavigationEndpoint.ts
new file mode 100644
index 0000000..514cf98
--- /dev/null
+++ b/src/NavigationEndpoint.ts
@@ -0,0 +1,18 @@
+import {
+    Direction,
+    MazeTile,
+} from "./MazeMap";
+
+export function startGame(): MazeTile
+{
+    const StartingPoint = new MazeTile("start");
+    StartingPoint.paths.push(Direction.right);
+    return StartingPoint;
+}
+
+export function navigate(currentPosition:string, direction:Direction): MazeTile
+{
+    const newPosition = new MazeTile("");
+    newPosition.paths.push(Direction.left);
+    return newPosition;
+}

diff --git a/package-lock.json b/package-lock.json
index 11bfc83..4842d07 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,5 +1,261 @@
 {
   "name": "labyrinth",
   "version": "0.1.0",
-  "lockfileVersion": 1
+  "lockfileVersion": 1,
+  "requires": true,
+  "dependencies": {
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+      "dev": true
+    },
+    "@types/mocha": {
+      "version": "5.2.5",
+      "resolved": "https://registry.npmjs.org/@types/mocha/-/mocha-5.2.5.tgz",
+      "integrity": "sha512-lAVp+Kj54ui/vLUFxsJTMtWvZraZxum3w3Nwkble2dNuV5VnPA+Mi2oGX9XYJAaIvZi3tn3cbjS/qcJXRb6Bww==",
+      "dev": true
+    },
+    "assertion-error": {
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/assertion-error/-/assertion-error-1.1.0.tgz",
+      "integrity": "sha512-jgsaNduz+ndvGyFt3uSuWqvy4lCnIJiovtouQN5JZHOKCS2QuhEdbcQHFhVksz2N2U9hXJo8odG7ETyWlEeuDw==",
+      "dev": true
+    },
+    "balanced-match": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/balanced-match/-/balanced-match-1.0.0.tgz",
+      "integrity": "sha1-ibTRmasr7kneFk6gK4nORi1xt2c=",
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+    },
+    "brace-expansion": {
+      "version": "1.1.11",
+      "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.11.tgz",
+      "integrity": "sha512-iCuPHDFgrHX7H2vEI/5xpz07zSHB00TpugqhmYtVmMO6518mCuRMoOYFldEBl0g187ufozdaHgWKcYFb61qGiA==",
+      "dev": true,
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 }
diff --git a/package.json b/package.json
index 18ea9f2..67f823a 100644
--- a/package.json
+++ b/package.json
@@ -1,12 +1,26 @@
 {
   "name": "labyrinth",
   "version": "0.1.0",
-  "description": "",
+  "description": "Labyrinth =========",
   "main": "app.js",
   "scripts": {
-    "test": "echo \"Error: no test specified\" && exit 1"
+    "test": "tsc && ./node_modules/mocha/bin/mocha dist/**/*.spec.js"
   },
   "author": "Peter Zilz",
   "license": "ISC",
-  "dependencies": {}
+  "dependencies": {},
+  "devDependencies": {
+    "@types/chai": "^4.1.6",
+    "@types/mocha": "^5.2.5",
+    "chai": "^4.2.0",
+    "mocha": "^5.2.0"
+  },
+  "repository": {
+    "type": "git",
+    "url": "http://git.synoikos.de/git/peter/Labyrinth.git"
+  },
+  "keywords": [
+    "TypeScript",
+    "game"
+  ]
 }
diff --git a/src/NavigationEndpoint.spec.ts b/src/NavigationEndpoint.spec.ts
new file mode 100644
index 0000000..83588f1
--- /dev/null
+++ b/src/NavigationEndpoint.spec.ts
@@ -0,0 +1,68 @@
+// to get rid of "[ts] could not find module ..." in vs code realod the window: f1 -> type "reload window"
+// official issue for this: https://github.com/Microsoft/TypeScript/issues/10346
+
+import {expect} from "chai";
+import { Direction } from "./MazeMap";
+// import { describe, it } from "mocha";
+import {navigate, startGame} from "./NavigationEndpoint";
+
+describe("Scenario: Starting the game", function(){
+    describe("when the game is started", function(){
+        const position = startGame();
+
+        it("then the start position must exist", function(){
+            expect(position).to.be.not.null;
+        });
+
+        it("then the position must have at least one pathway", function(){
+            expect(position.paths.length).to.be.greaterThan(0);
+        });
+    });
+});
+
+describe("Scenario: Navigating in ongoing game", function(){
+    const startPosition = startGame();
+
+    describe("When player navigates in existing direction", function(){
+        const naviagtionDirection = startPosition.paths[0];
+        const nextPosition = navigate(startPosition.id, naviagtionDirection);
+        it("then the new position has to have a different id", function(){
+            expect(nextPosition.id).to.not.equal(startPosition.id);
+        });
+
+        it("then the new position must have pathway back", function(){
+            let hasOpposite:boolean = false;
+            for (const dir of nextPosition.paths) {
+                switch (dir) {
+                    case Direction.top:
+                        if(naviagtionDirection === Direction.bottom)
+                        {
+                            hasOpposite = true;
+                        }
+                        break;
+                    case Direction.left:
+                        if(naviagtionDirection === Direction.right)
+                        {
+                            hasOpposite = true;
+                        }
+                        break;
+                    case Direction.bottom:
+                        if(naviagtionDirection === Direction.top)
+                        {
+                            hasOpposite = true;
+                        }
+                        break;
+                    case Direction.right:
+                        if(naviagtionDirection === Direction.left)
+                        {
+                            hasOpposite = true;
+                        }
+                        break;
+                    default:
+                        throw new Error(`Direction "${dir}" not recognized.`);
+                }
+            }
+            expect(hasOpposite).to.be.true;
+        });
+    });
+});
diff --git a/src/NavigationEndpoint.ts b/src/NavigationEndpoint.ts
new file mode 100644
index 0000000..514cf98
--- /dev/null
+++ b/src/NavigationEndpoint.ts
@@ -0,0 +1,18 @@
+import {
+    Direction,
+    MazeTile,
+} from "./MazeMap";
+
+export function startGame(): MazeTile
+{
+    const StartingPoint = new MazeTile("start");
+    StartingPoint.paths.push(Direction.right);
+    return StartingPoint;
+}
+
+export function navigate(currentPosition:string, direction:Direction): MazeTile
+{
+    const newPosition = new MazeTile("");
+    newPosition.paths.push(Direction.left);
+    return newPosition;
+}
diff --git a/tslint.json b/tslint.json
index 58f9a35..8c73a4d 100644
--- a/tslint.json
+++ b/tslint.json
@@ -10,7 +10,9 @@
         "typedef-whitespace":false,
         "whitespace": false,
         "no-bitwise": false,
-        "max-classes-per-file":false
+        "max-classes-per-file":false,
+        "only-arrow-functions": false,
+        "no-unused-expression": false
     },
     "rulesDirectory": [],
     "linterOptions": {