diff --git a/src/dice.ts b/src/dice.ts
index 91718fa..bebc616 100644
--- a/src/dice.ts
+++ b/src/dice.ts
@@ -24,7 +24,7 @@ function validateDiceString(input: string): boolean {
 
 function diceToDieArr({ amount, sides }: Dice): Die[] {
   if (amount === 0) return []
-  return new Array(Math.abs(amount)).fill(amount / Math.abs(amount) * sides)
+  return new Array(Math.abs(amount)).fill({sides: amount / Math.abs(amount) * sides})
 }
 
 export function parseDice(inputStr: string): Dice[] | null {
@@ -74,7 +74,7 @@ export function calculateMin(dice: Dice[]) {
 }
 
 export function getDistribution(dice: Dice[]) {
-  const diceRanges = dice.flatMap(diceToDieArr).map(rangeTo)
+  const diceRanges = dice.flatMap(diceToDieArr).map(die => rangeTo(die.sides))
   const possibleResults = cartesian(diceRanges)
   return possibleResults.map(resultArr => resultArr.reduce((a, b) => a + b, 0)).sort((a, b) => a - b)
 }
diff --git a/src/utils.ts b/src/utils.ts
index 3ab5170..6e978ed 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -1,4 +1,4 @@
-export function rangeTo(n) {
+export function rangeTo(n: number) {
   if (n === 0) return []
   return new Array(Math.abs(n)).fill(undefined).map((_, i) => n / Math.abs(n) * (i + 1))
 }
diff --git a/tsconfig.json b/tsconfig.json
new file mode 100644
index 0000000..37a23fc
--- /dev/null
+++ b/tsconfig.json
@@ -0,0 +1,11 @@
+{
+  "compilerOptions": {
+    "target": "ES2016",
+    "module": "commonjs",
+    "sourceMap": false,
+    "strict": true,
+    "esModuleInterop": true,
+    "inlineSourceMap": false,
+    "inlineSources": false
+  }
+}
\ No newline at end of file