diff --git a/functions/src/day17.ts b/functions/src/day17.ts
new file mode 100644
index 0000000..96d0548
--- /dev/null
+++ b/functions/src/day17.ts
@@ -0,0 +1,123 @@
+import Day from "./day";
+
+class Day17 implements Day {
+
+  part1(input: string[]): number | string {
+
+    const targetArea = TargetArea.parse(input[0]);
+
+    // First we find all x-es between 1 and maxX + 1 (as all others will immediately overshoot), that overlap with the target at some points:
+    for (let x = 1; x <= targetArea.maxX + 1; x++) {
+      let curSpeed = x;
+      let curPosX = 0;
+      for (let step = 0; step < (targetArea.maxX + 1) / x; step++) {
+
+        curPosX += curSpeed;
+        if (targetArea.isInX(curPosX)) {
+          // Find y's that given this position and step, match:
+          // TODO: find out which y's make sense to check
+          for (let y = 0; y < 100; y++) {
+            // steps = 3
+            // y = 1 -> 1 + 0 + -1 = 0
+            // y = 2 -> 2 + 1 + 0 = 3
+            // y = 3 -> 3 + 2 + 1 = 6
+            // y = 4 -> 4 + 3 + 2 = 9
+            // y = 5 -> 5 + 4 + 3 = 12
+
+            // steps = 4
+            // y = 1 -> -2
+            // y = 2 -> 2
+            // y = 3 -> 6
+            // y = 4 -> 10
+
+            // y = 0
+            // steps = 1 -> 0            =  0
+            // steps = 2 -> 0 - 1       =  -1
+            // steps = 3 -> 0 - 1 - 2   =  -3
+            // steps = 4 -> 0 - 1- 2 - 3=  -6
+            // steps = 5 -> 0-1-2-3-4   = -10
+            // steps = 6 -> 0-1-2-3-4-5 = -15
+
+            // v = -1 * x
+            // pos = -.5 * steps^2 + y * steps
+
+            // f(s) = s * y +
+          }
+          const { maxY, finalY } = this.simulateY() 
+        } else if ( curPosX > targetArea.maxX || (curSpeed === 0 && curPosX < targetArea.minX)) {
+          break;
+        }
+        curSpeed--;
+      }
+    }
+
+    return 0;
+  }
+
+  simulateY(initialSpeedY: number, steps: number): { maxY: number, finalY: number} {
+
+    let curSpeed = initialSpeedY;
+    let y = 0;
+    let maxY = 0;
+    for (let step = 0; step < steps; step++) {
+      y += curSpeed;
+      curSpeed--;
+      if (y > maxY) {
+        maxY = y;
+      }
+    }
+    return { finalY: y, maxY: maxY };
+  }
+
+  part2(input: string[]): number | string {
+    // TODO implement
+    return 0;
+  }
+
+}
+
+class TargetArea {
+
+  minX: number;
+  maxX: number;
+  minY: number;
+  maxY: number;
+
+
+  constructor(minX: number, maxX: number, minY: number, maxY: number) {
+    this.minX = minX;
+    this.maxX = maxX;
+    this.minY = minY;
+    this.maxY = maxY;
+  }
+
+  static parse(input: string): TargetArea {
+    const regex = /^target area: x=(-?[0-9]+)\.\.(-?[0-9]+), y=(-?[0-9]+)..(-?[0-9]+)$/i;
+    const match = input.trim().match(regex);
+
+    if (!match || match.length < 5) {
+      throw Error("Invalid input: '" + input + "'");
+    }
+
+    return new TargetArea(
+        parseInt(match[1]),
+        parseInt(match[2]),
+        parseInt(match[3]),
+        parseInt(match[4]),
+    )
+  }
+
+  isInX(x: number): boolean {
+    return x >= this.minX && x <= this.maxX;
+  }
+
+  isInY(y: number): boolean {
+    return y >= this.minY && y <= this.maxY;
+  }
+
+  isIn(x: number, y: number): boolean {
+    return this.isInX(x) && this.isInY(y);
+  }
+}
+
+export default Day17;
diff --git a/functions/src/index.ts b/functions/src/index.ts
index ea0b90b..5b4ea3d 100644
--- a/functions/src/index.ts
+++ b/functions/src/index.ts
@@ -18,6 +18,7 @@ import Day13 from "./day13";
 import Day14 from "./day14";
 import Day15 from "./day15";
 import Day16 from "./day16";
+import Day17 from './day17';
 
 
 // // Start writing Firebase Functions
@@ -50,6 +51,7 @@ export const day = {
   14: functions.region("europe-west1").https.onRequest((request, response) => { processDay(new Day14(), request, response) }),
   15: functions.region("europe-west1").https.onRequest((request, response) => { processDay(new Day15(), request, response) }),
   16: functions.region("europe-west1").https.onRequest((request, response) => { processDay(new Day16(), request, response) }),
+  17: functions.region("europe-west1").https.onRequest((request, response) => { processDay(new Day17(), request, response) }),
 
 }