diff --git a/.prettierrc b/.prettierrc
index 963354f..856eb3e 100644
--- a/.prettierrc
+++ b/.prettierrc
@@ -1,3 +1,4 @@
 {
-  "printWidth": 120
+  "printWidth": 120,
+  "trailingComma": "all"
 }
diff --git a/src/generateZwo.ts b/src/generateZwo.ts
index 6d3c394..0e1493a 100644
--- a/src/generateZwo.ts
+++ b/src/generateZwo.ts
@@ -5,7 +5,7 @@ import { Interval, Workout } from "./ast";
 
 const generateRangeInterval = (
   tagName: "Warmup" | "Cooldown",
-  { duration, intensity, cadence }: Interval
+  { duration, intensity, cadence }: Interval,
 ): xml.XmlObject => {
   return {
     [tagName]: [
@@ -57,6 +57,6 @@ export const generateZwo = ({ name, author, description, intervals }: Workout):
         ...intervals.map(generateInterval),
       ],
     },
-    { indent: "  " }
+    { indent: "  " },
   );
 };
diff --git a/src/parser/parser.test.ts b/src/parser/parser.test.ts
index e2cc13d..79c10ec 100644
--- a/src/parser/parser.test.ts
+++ b/src/parser/parser.test.ts
@@ -3,11 +3,11 @@ import { parse } from ".";
 describe("Parser", () => {
   it("throws error for empty file", () => {
     expect(() => parse("")).toThrowErrorMatchingInlineSnapshot(
-      `"Workout is missing a name. Use \`Name:\` to declare one. at line 1 char 1"`
+      `"Workout is missing a name. Use \`Name:\` to declare one. at line 1 char 1"`,
     );
 
     expect(() => parse("  \n  \n \t")).toThrowErrorMatchingInlineSnapshot(
-      `"Workout is missing a name. Use \`Name:\` to declare one. at line 1 char 1"`
+      `"Workout is missing a name. Use \`Name:\` to declare one. at line 1 char 1"`,
     );
   });
 
@@ -32,7 +32,7 @@ Description:
   
   Do it when you dare,
   it'll cause lots of pain.
-`)
+`),
     ).toMatchInlineSnapshot(`
       Object {
         "author": "John Doe",
@@ -56,7 +56,7 @@ Rest: 5:00 50%
 Interval: 10:00 80% 90rpm
 
 Rest: 5:00 45%
-`).intervals
+`).intervals,
     ).toMatchInlineSnapshot(`
       Array [
         Object {
@@ -97,7 +97,7 @@ Name: My Workout
 
 Warmup: 5:30 50%..80% 100rpm
 Cooldown: 5:30 70%..45%
-`).intervals
+`).intervals,
     ).toMatchInlineSnapshot(`
       Array [
         Object {
@@ -126,13 +126,13 @@ Cooldown: 5:30 70%..45%
 
   it("requires duration and power parameters to be specified", () => {
     expect(() => parseInterval("Interval: 50%")).toThrowErrorMatchingInlineSnapshot(
-      `"Duration not specified at line 2 char 1"`
+      `"Duration not specified at line 2 char 1"`,
     );
     expect(() => parseInterval("Interval: 30:00")).toThrowErrorMatchingInlineSnapshot(
-      `"Power not specified at line 2 char 1"`
+      `"Power not specified at line 2 char 1"`,
     );
     expect(() => parseInterval("Interval: 10rpm")).toThrowErrorMatchingInlineSnapshot(
-      `"Duration not specified at line 2 char 1"`
+      `"Duration not specified at line 2 char 1"`,
     );
   });
 
@@ -210,34 +210,34 @@ Cooldown: 5:30 70%..45%
 
   it("throws error for incorrect duration formats", () => {
     expect(() => parseInterval("Interval: 10 50%")).toThrowErrorMatchingInlineSnapshot(
-      `"Unrecognized interval parameter \\"10\\" at line 2 char 11"`
+      `"Unrecognized interval parameter \\"10\\" at line 2 char 11"`,
     );
     expect(() => parseInterval("Interval: :10 50%")).toThrowErrorMatchingInlineSnapshot(
-      `"Unrecognized interval parameter \\":10\\" at line 2 char 11"`
+      `"Unrecognized interval parameter \\":10\\" at line 2 char 11"`,
     );
     expect(() => parseInterval("Interval: 0:100 50%")).toThrowErrorMatchingInlineSnapshot(
-      `"Unrecognized interval parameter \\"0:100\\" at line 2 char 11"`
+      `"Unrecognized interval parameter \\"0:100\\" at line 2 char 11"`,
     );
     expect(() => parseInterval("Interval: 00:00:00:10 50%")).toThrowErrorMatchingInlineSnapshot(
-      `"Unrecognized interval parameter \\"00:00:00:10\\" at line 2 char 11"`
+      `"Unrecognized interval parameter \\"00:00:00:10\\" at line 2 char 11"`,
     );
   });
 
   it("throws error for unexpected interval parameter", () => {
     expect(() => parseInterval("Interval: 10:00 50% foobar")).toThrowErrorMatchingInlineSnapshot(
-      `"Unrecognized interval parameter \\"foobar\\" at line 2 char 21"`
+      `"Unrecognized interval parameter \\"foobar\\" at line 2 char 21"`,
     );
     expect(() => parseInterval("Interval: 10:00 50% 123blah")).toThrowErrorMatchingInlineSnapshot(
-      `"Unrecognized interval parameter \\"123blah\\" at line 2 char 21"`
+      `"Unrecognized interval parameter \\"123blah\\" at line 2 char 21"`,
     );
     expect(() => parseInterval("Interval: 10:00 50% ^*&")).toThrowErrorMatchingInlineSnapshot(
-      `"Unrecognized interval parameter \\"^*&\\" at line 2 char 21"`
+      `"Unrecognized interval parameter \\"^*&\\" at line 2 char 21"`,
     );
   });
 
   it("throws error for unexpected type of interval", () => {
     expect(() => parseInterval("Interval: 30:00 5% \n CustomInterval: 15:00 10%")).toThrowErrorMatchingInlineSnapshot(
-      `"Unexpected token [text CustomInterval: 15:00 10%] at line 3 char 1"`
+      `"Unexpected token [text CustomInterval: 15:00 10%] at line 3 char 1"`,
     );
   });
 });
diff --git a/src/stats/normalizedIntensity.ts b/src/stats/normalizedIntensity.ts
index 22f0717..5af676f 100644
--- a/src/stats/normalizedIntensity.ts
+++ b/src/stats/normalizedIntensity.ts
@@ -30,6 +30,6 @@ export const normalizedIntensity = (intervals: Interval[]): number => {
     rollingAverages,
     (averages) => averages.map(fourthPower),
     average,
-    fourthRoot
+    fourthRoot,
   )(intervals);
 };