From 9059665ed2982c845a8728241051cb376b143fcd Mon Sep 17 00:00:00 2001
From: greptile-bot <abhinav+1@greptile.com>
Date: Sat, 25 Jul 2026 14:51:54 -0700
Subject: [PATCH] Add tax calculation

---
 src/tax.ts | 10 ++++++++++
 1 file changed, 10 insertions(+)
 create mode 100644 src/tax.ts

diff --git a/src/tax.ts b/src/tax.ts
new file mode 100644
index 0000000..bb1b61f
--- /dev/null
+++ b/src/tax.ts
@@ -0,0 +1,10 @@
+import { totalCents, type CartItem, type Discount } from './cart'
+
+export function totalWithTaxCents(
+  items: CartItem[],
+  taxRatePercent: number,
+  discount?: Discount,
+): number {
+  const base = totalCents(items, discount)
+  return base + base * (taxRatePercent / 100)
+}