diff --git a/supabase/functions/_shared/email.test.ts b/supabase/functions/_shared/email.test.ts
new file mode 100644
index 0000000..9961f06
--- /dev/null
+++ b/supabase/functions/_shared/email.test.ts
@@ -0,0 +1,49 @@
+import { assertEquals, assertStringIncludes } from 'jsr:@std/assert'
+import { buildBookingNotificationEmail, buildInquiryNotificationEmail } from './email.ts'
+
+Deno.test('buildBookingNotificationEmail includes the service, date, time, and contact details', () => {
+  const { subject, html } = buildBookingNotificationEmail({
+    serviceName: 'Knotless Braids',
+    date: '2026-09-01',
+    time: '10:00 AM',
+    contact: { name: 'Jane Doe', phone: '555-0100', email: 'jane@example.com', notes: 'First time client' },
+  })
+  assertEquals(subject, 'New booking: Knotless Braids on 2026-09-01')
+  assertStringIncludes(html, 'Jane Doe')
+  assertStringIncludes(html, 'Knotless Braids')
+  assertStringIncludes(html, '2026-09-01')
+  assertStringIncludes(html, '10:00 AM')
+  assertStringIncludes(html, '555-0100')
+  assertStringIncludes(html, 'jane@example.com')
+  assertStringIncludes(html, 'First time client')
+})
+
+Deno.test('buildBookingNotificationEmail omits the notes paragraph when notes are empty', () => {
+  const { html } = buildBookingNotificationEmail({
+    serviceName: 'Cornrows',
+    date: '2026-09-02',
+    time: '1:00 PM',
+    contact: { name: 'Amy', phone: '555-0101', email: 'amy@example.com', notes: '' },
+  })
+  if (html.includes('Notes:')) throw new Error('expected no Notes: paragraph')
+})
+
+Deno.test('buildInquiryNotificationEmail includes the product and contact details', () => {
+  const { subject, html } = buildInquiryNotificationEmail({
+    productName: 'Silk Edge Control',
+    contact: { name: 'Nadia', email: 'nadia@example.com', notes: 'Is this in stock?' },
+  })
+  assertEquals(subject, 'New inquiry: Silk Edge Control')
+  assertStringIncludes(html, 'Nadia')
+  assertStringIncludes(html, 'nadia@example.com')
+  assertStringIncludes(html, 'Silk Edge Control')
+  assertStringIncludes(html, 'Is this in stock?')
+})
+
+Deno.test('buildInquiryNotificationEmail omits the notes paragraph when notes are empty', () => {
+  const { html } = buildInquiryNotificationEmail({
+    productName: 'Braid Oil',
+    contact: { name: 'Kim', email: 'kim@example.com', notes: '' },
+  })
+  if (html.includes('Notes:')) throw new Error('expected no Notes: paragraph')
+})
diff --git a/supabase/functions/_shared/email.ts b/supabase/functions/_shared/email.ts
new file mode 100644
index 0000000..cf8eb89
--- /dev/null
+++ b/supabase/functions/_shared/email.ts
@@ -0,0 +1,28 @@
+export interface BookingEmailInput {
+  serviceName: string
+  date: string
+  time: string
+  contact: { name: string; phone: string; email: string; notes: string }
+}
+
+export function buildBookingNotificationEmail(input: BookingEmailInput): { subject: string; html: string } {
+  const notesLine = input.contact.notes ? `<p>Notes: ${input.contact.notes}</p>` : ''
+  return {
+    subject: `New booking: ${input.serviceName} on ${input.date}`,
+    html: `<p><strong>${input.contact.name}</strong> booked <strong>${input.serviceName}</strong> on ${input.date} at ${input.time}.</p>` +
+      `<p>Phone: ${input.contact.phone}<br/>Email: ${input.contact.email}</p>${notesLine}`,
+  }
+}
+
+export interface InquiryEmailInput {
+  productName: string
+  contact: { name: string; email: string; notes: string }
+}
+
+export function buildInquiryNotificationEmail(input: InquiryEmailInput): { subject: string; html: string } {
+  const notesLine = input.contact.notes ? `<p>Notes: ${input.contact.notes}</p>` : ''
+  return {
+    subject: `New inquiry: ${input.productName}`,
+    html: `<p><strong>${input.contact.name}</strong> (${input.contact.email}) asked about <strong>${input.productName}</strong>.</p>${notesLine}`,
+  }
+}
diff --git a/supabase/functions/deno.json b/supabase/functions/deno.json
new file mode 100644
index 0000000..8ab0875
--- /dev/null
+++ b/supabase/functions/deno.json
@@ -0,0 +1,5 @@
+{
+  "tasks": {
+    "test": "deno test --allow-none"
+  }
+}
diff --git a/supabase/functions/deno.lock b/supabase/functions/deno.lock
new file mode 100644
index 0000000..a4437a0
--- /dev/null
+++ b/supabase/functions/deno.lock
@@ -0,0 +1,18 @@
+{
+  "version": "5",
+  "specifiers": {
+    "jsr:@std/assert@*": "1.0.19",
+    "jsr:@std/internal@^1.0.12": "1.0.14"
+  },
+  "jsr": {
+    "@std/assert@1.0.19": {
+      "integrity": "eaada96ee120cb980bc47e040f82814d786fe8162ecc53c91d8df60b8755991e",
+      "dependencies": [
+        "jsr:@std/internal"
+      ]
+    },
+    "@std/internal@1.0.14": {
+      "integrity": "291516b3d4c35024d6ffbc0a9df5bf4c64116e05b50012cf846710152d2ffdf7"
+    }
+  }
+}
diff --git a/vite.config.ts b/vite.config.ts
index 32ba018..5bc4af7 100644
--- a/vite.config.ts
+++ b/vite.config.ts
@@ -14,6 +14,7 @@ export default defineConfig({
       '**/cypress/**',
       '**/.{idea,git,cache,output,temp}/**',
       '**/{karma,rollup,webpack,vite,vitest,jest,ava,babel,nyc,cypress,tsup,build}.config.*',
+      'supabase/functions/**',
     ],
   },
 })