diff --git a/src/app/groups/[groupId]/expenses/[expenseId]/edit/loading.tsx b/src/app/groups/[groupId]/expenses/[expenseId]/edit/loading.tsx
new file mode 100644
index 0000000..2b6ca56
--- /dev/null
+++ b/src/app/groups/[groupId]/expenses/[expenseId]/edit/loading.tsx
@@ -0,0 +1,3 @@
+export default function Loading() {
+  return <p>Loading…</p>
+}
diff --git a/src/app/groups/[groupId]/layout.tsx b/src/app/groups/[groupId]/layout.tsx
new file mode 100644
index 0000000..f8030c6
--- /dev/null
+++ b/src/app/groups/[groupId]/layout.tsx
@@ -0,0 +1,37 @@
+import { Button } from '@/components/ui/button'
+import { getGroup } from '@/lib/api'
+import { ChevronLeft, Edit } from 'lucide-react'
+import Link from 'next/link'
+import { notFound } from 'next/navigation'
+import { PropsWithChildren } from 'react'
+
+export default async function GroupLayout({
+  children,
+  params: { groupId },
+}: PropsWithChildren<{
+  params: { groupId: string }
+}>) {
+  const group = await getGroup(groupId)
+  if (!group) notFound()
+
+  return (
+    <main>
+      <div className="mb-4 flex justify-between">
+        <Button variant="ghost" asChild>
+          <Link href="/groups">
+            <ChevronLeft className="w-4 h-4 mr-2" /> Back to recent groups
+          </Link>
+        </Button>
+        <Button variant="secondary" asChild>
+          <Link href={`/groups/${groupId}/edit`}>
+            <Edit className="w-4 h-4 mr-2" /> Edit group settings
+          </Link>
+        </Button>
+      </div>
+
+      <h1 className="font-bold mb-4">{group.name}</h1>
+
+      {children}
+    </main>
+  )
+}
diff --git a/src/app/groups/[groupId]/loading.tsx b/src/app/groups/[groupId]/loading.tsx
new file mode 100644
index 0000000..2b6ca56
--- /dev/null
+++ b/src/app/groups/[groupId]/loading.tsx
@@ -0,0 +1,3 @@
+export default function Loading() {
+  return <p>Loading…</p>
+}
diff --git a/src/app/groups/[groupId]/page.tsx b/src/app/groups/[groupId]/page.tsx
index 1577d7a..9547fcc 100644
--- a/src/app/groups/[groupId]/page.tsx
+++ b/src/app/groups/[groupId]/page.tsx
@@ -17,7 +17,7 @@ import {
   TableRow,
 } from '@/components/ui/table'
 import { getGroup, getGroupExpenses } from '@/lib/api'
-import { ChevronLeft, ChevronRight, Edit, Plus } from 'lucide-react'
+import { ChevronRight, Plus } from 'lucide-react'
 import Link from 'next/link'
 import { notFound } from 'next/navigation'
 
@@ -32,22 +32,7 @@ export default async function GroupPage({
   const expenses = await getGroupExpenses(groupId)
 
   return (
-    <main>
-      <div className="mb-4 flex justify-between">
-        <Button variant="ghost" asChild>
-          <Link href="/groups">
-            <ChevronLeft className="w-4 h-4 mr-2" /> Back to recent groups
-          </Link>
-        </Button>
-        <Button variant="secondary" asChild>
-          <Link href={`/groups/${groupId}/edit`}>
-            <Edit className="w-4 h-4 mr-2" /> Edit group settings
-          </Link>
-        </Button>
-      </div>
-
-      <h1 className="font-bold mb-4">{group.name}</h1>
-
+    <>
       <Card className="mb-4">
         <div className="flex flex-1">
           <CardHeader className="flex-1">
@@ -136,6 +121,6 @@ export default async function GroupPage({
         </CardContent>
       </Card>
       <SaveGroupLocally group={{ id: group.id, name: group.name }} />
-    </main>
+    </>
   )
 }
diff --git a/src/app/groups/loading.tsx b/src/app/groups/loading.tsx
new file mode 100644
index 0000000..2b6ca56
--- /dev/null
+++ b/src/app/groups/loading.tsx
@@ -0,0 +1,3 @@
+export default function Loading() {
+  return <p>Loading…</p>
+}
diff --git a/src/app/loading.tsx b/src/app/loading.tsx
new file mode 100644
index 0000000..2b6ca56
--- /dev/null
+++ b/src/app/loading.tsx
@@ -0,0 +1,3 @@
+export default function Loading() {
+  return <p>Loading…</p>
+}
diff --git a/src/components/expense-form.tsx b/src/components/expense-form.tsx
index 056d25e..f7826c6 100644
--- a/src/components/expense-form.tsx
+++ b/src/components/expense-form.tsx
@@ -1,5 +1,5 @@
 'use client'
-import { Button } from '@/components/ui/button'
+import { SubmitButton } from '@/components/submit-button'
 import {
   Card,
   CardContent,
@@ -175,9 +175,7 @@ export function ExpenseForm({ group, expense, onSubmit }: Props) {
           </CardContent>
 
           <CardFooter>
-            <Button variant="secondary" type="submit">
-              Submit
-            </Button>
+            <SubmitButton loadingContent="Submitting…">Submit</SubmitButton>
           </CardFooter>
         </Card>
       </form>
diff --git a/src/components/group-form.tsx b/src/components/group-form.tsx
index 0b6e560..9841cc5 100644
--- a/src/components/group-form.tsx
+++ b/src/components/group-form.tsx
@@ -1,4 +1,5 @@
 'use client'
+import { SubmitButton } from '@/components/submit-button'
 import { Button } from '@/components/ui/button'
 import {
   Card,
@@ -25,7 +26,7 @@ import { useFieldArray, useForm } from 'react-hook-form'
 
 export type Props = {
   group?: NonNullable<Awaited<ReturnType<typeof getGroup>>>
-  onSubmit: (groupFormValues: GroupFormValues) => void
+  onSubmit: (groupFormValues: GroupFormValues) => Promise<void>
 }
 
 export function GroupForm({ group, onSubmit }: Props) {
@@ -49,8 +50,8 @@ export function GroupForm({ group, onSubmit }: Props) {
   return (
     <Form {...form}>
       <form
-        onSubmit={form.handleSubmit((values) => {
-          onSubmit(values)
+        onSubmit={form.handleSubmit(async (values) => {
+          await onSubmit(values)
         })}
         className="space-y-8"
       >
@@ -129,7 +130,7 @@ export function GroupForm({ group, onSubmit }: Props) {
           </CardFooter>
         </Card>
 
-        <Button type="submit">Submit</Button>
+        <SubmitButton loadingContent="Submitting…">Submit</SubmitButton>
       </form>
     </Form>
   )
diff --git a/src/components/submit-button.tsx b/src/components/submit-button.tsx
new file mode 100644
index 0000000..7489c6c
--- /dev/null
+++ b/src/components/submit-button.tsx
@@ -0,0 +1,23 @@
+import { Button } from '@/components/ui/button'
+import { Loader2 } from 'lucide-react'
+import { PropsWithChildren, ReactNode } from 'react'
+import { useFormState } from 'react-hook-form'
+
+type Props = PropsWithChildren<{
+  loadingContent: ReactNode
+}>
+
+export function SubmitButton({ children, loadingContent }: Props) {
+  const { isSubmitting } = useFormState()
+  return (
+    <Button type="submit" disabled={isSubmitting}>
+      {isSubmitting ? (
+        <>
+          <Loader2 className="w-4 h-4 mr-2 animate-spin" /> {loadingContent}
+        </>
+      ) : (
+        children
+      )}
+    </Button>
+  )
+}
diff --git a/src/lib/api.ts b/src/lib/api.ts
index 6ea26f4..10f0b3d 100644
--- a/src/lib/api.ts
+++ b/src/lib/api.ts
@@ -4,7 +4,8 @@ import { Expense } from '@prisma/client'
 import { v4 as uuidv4 } from 'uuid'
 
 export async function createGroup(groupFormValues: GroupFormValues) {
-  return getPrisma().group.create({
+  const prisma = await getPrisma()
+  return prisma.group.create({
     data: {
       id: uuidv4(),
       name: groupFormValues.name,
@@ -36,7 +37,8 @@ export async function createExpense(
       throw new Error(`Invalid participant ID: ${participant}`)
   }
 
-  return getPrisma().expense.create({
+  const prisma = await getPrisma()
+  return prisma.expense.create({
     data: {
       id: uuidv4(),
       groupId,
@@ -73,7 +75,8 @@ export async function updateExpense(
       throw new Error(`Invalid participant ID: ${participant}`)
   }
 
-  return getPrisma().expense.update({
+  const prisma = await getPrisma()
+  return prisma.expense.update({
     where: { id: expenseId },
     data: {
       amount: expenseFormValues.amount,
@@ -104,7 +107,8 @@ export async function updateGroup(
   const existingGroup = await getGroup(groupId)
   if (!existingGroup) throw new Error('Invalid group ID')
 
-  return getPrisma().group.update({
+  const prisma = await getPrisma()
+  return prisma.group.update({
     where: { id: groupId },
     data: {
       name: groupFormValues.name,
@@ -134,21 +138,24 @@ export async function updateGroup(
 }
 
 export async function getGroup(groupId: string) {
-  return getPrisma().group.findUnique({
+  const prisma = await getPrisma()
+  return prisma.group.findUnique({
     where: { id: groupId },
     include: { participants: true },
   })
 }
 
 export async function getGroupExpenses(groupId: string) {
-  return getPrisma().expense.findMany({
+  const prisma = await getPrisma()
+  return prisma.expense.findMany({
     where: { groupId },
     include: { paidFor: { include: { participant: true } }, paidBy: true },
   })
 }
 
 export async function getExpense(groupId: string, expenseId: string) {
-  return getPrisma().expense.findUnique({
+  const prisma = await getPrisma()
+  return prisma.expense.findUnique({
     where: { id: expenseId },
     include: { paidBy: true, paidFor: true },
   })
diff --git a/src/lib/prisma.ts b/src/lib/prisma.ts
index 773547e..210e691 100644
--- a/src/lib/prisma.ts
+++ b/src/lib/prisma.ts
@@ -2,7 +2,7 @@ import { PrismaClient } from '@prisma/client'
 
 let prisma: PrismaClient
 
-export function getPrisma() {
+export async function getPrisma() {
   if (!prisma) {
     if (process.env.NODE_ENV === 'production') {
       prisma = new PrismaClient()
diff --git a/src/lib/utils.ts b/src/lib/utils.ts
index ec79801..502daf3 100644
--- a/src/lib/utils.ts
+++ b/src/lib/utils.ts
@@ -1,6 +1,10 @@
-import { type ClassValue, clsx } from "clsx"
-import { twMerge } from "tailwind-merge"
- 
+import { clsx, type ClassValue } from 'clsx'
+import { twMerge } from 'tailwind-merge'
+
 export function cn(...inputs: ClassValue[]) {
   return twMerge(clsx(inputs))
 }
+
+export function delay(ms: number) {
+  return new Promise((resolve) => setTimeout(resolve, ms))
+}