diff --git a/src/components/AccountSummary.tsx b/src/components/AccountSummary.tsx
index 96158f0..4c38849 100644
--- a/src/components/AccountSummary.tsx
+++ b/src/components/AccountSummary.tsx
@@ -1,12 +1,11 @@
-import React, { useState, useEffect } from 'react';
 import { useStore } from '@nanostores/react';
+import type React from 'react';
+import { useEffect, useState } from 'react';
+import { currentAccountId as currentAccountIdStore, refreshKey } from '../stores/transactionStore';
 import type { Account } from '../types';
 import { formatCurrency } from '../utils';
-import { currentAccountId as currentAccountIdStore, refreshKey } from '../stores/transactionStore';
 
-interface AccountSummaryProps {
-  // No props needed, data comes from store and fetch
-}
+type AccountSummaryProps = {};
 
 export default function AccountSummary({}: AccountSummaryProps) {
   const currentAccountId = useStore(currentAccountIdStore);
diff --git a/src/components/AddTransactionForm.tsx b/src/components/AddTransactionForm.tsx
index 03f6b1b..230838c 100644
--- a/src/components/AddTransactionForm.tsx
+++ b/src/components/AddTransactionForm.tsx
@@ -1,16 +1,17 @@
-import React, { useState, useEffect } from 'react';
 import { useStore } from '@nanostores/react';
-import type { Transaction } from '../types';
+import type React from 'react';
+import { useEffect, useState } from 'react';
 // Import store atoms and actions
 import {
-  currentAccountId as currentAccountIdStore,
-  transactionToEdit as transactionToEditStore,
   cancelEditingTransaction,
+  currentAccountId as currentAccountIdStore,
   transactionSaved,
+  transactionToEdit as transactionToEditStore,
 } from '../stores/transactionStore';
+import type { Transaction } from '../types';
 
 // Remove props that now come from the store
-interface AddTransactionFormProps {}
+type AddTransactionFormProps = {};
 
 export default function AddTransactionForm({}: AddTransactionFormProps) {
   // --- Read state from store ---
@@ -87,7 +88,7 @@ export default function AddTransactionForm({}: AddTransactionFormProps) {
     if (!amount) {
       errors.push('Amount is required');
     } else {
-      const amountNum = parseFloat(amount);
+      const amountNum = Number.parseFloat(amount);
       if (isNaN(amountNum)) {
         errors.push('Amount must be a valid number');
       } else if (amountNum === 0) {
@@ -134,7 +135,7 @@ export default function AddTransactionForm({}: AddTransactionFormProps) {
         accountId: currentAccountId,
         date: date, // Send as YYYY-MM-DD string
         description: description.trim(),
-        amount: parseFloat(amount),
+        amount: Number.parseFloat(amount),
       };
 
       const method = editingId ? 'PUT' : 'POST';
diff --git a/src/components/TransactionTable.tsx b/src/components/TransactionTable.tsx
index ff4ce84..4a19a79 100644
--- a/src/components/TransactionTable.tsx
+++ b/src/components/TransactionTable.tsx
@@ -1,15 +1,15 @@
-import React, { useState, useEffect } from 'react';
 import { useStore } from '@nanostores/react';
+import React, { useState, useEffect } from 'react';
+import {
+  currentAccountId as currentAccountIdStore,
+  refreshKey,
+  startEditingTransaction,
+  triggerRefresh,
+} from '../stores/transactionStore';
 import type { Transaction } from '../types';
 import { formatCurrency, formatDate } from '../utils';
-import {
-  startEditingTransaction,
-  currentAccountId as currentAccountIdStore,
-  triggerRefresh,
-  refreshKey,
-} from '../stores/transactionStore';
 
-interface TransactionTableProps {}
+type TransactionTableProps = {};
 
 export default function TransactionTable({}: TransactionTableProps) {
   const currentAccountId = useStore(currentAccountIdStore);
@@ -47,7 +47,7 @@ export default function TransactionTable({}: TransactionTableProps) {
   }, [currentAccountId, refreshCounter]);
 
   const sortedTransactions = [...transactions].sort(
-    (a, b) => new Date(b.date).getTime() - new Date(a.date).getTime()
+    (a, b) => new Date(b.date).getTime() - new Date(a.date).getTime(),
   );
 
   const handleDelete = async (txnId: string) => {
@@ -76,7 +76,7 @@ export default function TransactionTable({}: TransactionTableProps) {
       console.log(`Transaction ${txnId} deleted successfully.`);
 
       setTransactions((currentTransactions) =>
-        currentTransactions.filter((txn) => txn.id !== txnId)
+        currentTransactions.filter((txn) => txn.id !== txnId),
       );
 
       triggerRefresh();
diff --git a/src/pages/api/transactions/[id]/index.ts b/src/pages/api/transactions/[id]/index.ts
index 5fd1f24..e0c3266 100644
--- a/src/pages/api/transactions/[id]/index.ts
+++ b/src/pages/api/transactions/[id]/index.ts
@@ -1,5 +1,5 @@
 import type { APIRoute } from 'astro';
-import { transactions, accounts } from '../../../../data/store';
+import { accounts, transactions } from '../../../../data/store';
 import type { Transaction } from '../../../../types';
 
 export const PUT: APIRoute = async ({ request, params }) => {
diff --git a/src/pages/api/transactions/index.ts b/src/pages/api/transactions/index.ts
index 212b461..57e1814 100644
--- a/src/pages/api/transactions/index.ts
+++ b/src/pages/api/transactions/index.ts
@@ -11,7 +11,7 @@
  */
 
 import type { APIRoute } from 'astro';
-import { transactions, accounts } from '../../../data/store';
+import { accounts, transactions } from '../../../data/store';
 import type { Transaction } from '../../../types';
 
 /**
diff --git a/src/server.ts b/src/server.ts
index 8b62898..52310d9 100644
--- a/src/server.ts
+++ b/src/server.ts
@@ -1,11 +1,11 @@
 // src/server.ts
 
-import Fastify, { FastifyInstance } from 'fastify';
-import { Server, IncomingMessage, ServerResponse } from 'http';
-import { PrismaClient, BankAccount } from '@prisma/client';
+import { IncomingMessage, Server, ServerResponse } from 'http';
+import { type BankAccount, PrismaClient } from '@prisma/client';
 import dotenv from 'dotenv';
+import Fastify, { type FastifyInstance } from 'fastify';
+import type { ZodTypeProvider } from 'fastify-type-provider-zod';
 import { z } from 'zod';
-import { ZodTypeProvider } from 'fastify-type-provider-zod';
 
 dotenv.config();
 
@@ -13,9 +13,9 @@ const prisma = new PrismaClient();
 
 // Base schema for common fields, useful for reuse
 const bankAccountBaseSchema = z.object({
-    name: z.string().min(1, { message: "Name cannot be empty" }),
-    bankName: z.string().min(1, { message: "Bank name cannot be empty" }),
-    accountNumber: z.string().min(1, { message: "Account number cannot be empty" }),
+  name: z.string().min(1, { message: 'Name cannot be empty' }),
+  bankName: z.string().min(1, { message: 'Bank name cannot be empty' }),
+  accountNumber: z.string().min(1, { message: 'Account number cannot be empty' }),
 });
 
 // Schema for creating a bank account (all fields required)
@@ -23,8 +23,8 @@ const createBankAccountSchema = bankAccountBaseSchema;
 
 // Schema for request parameters containing an ID
 const paramsSchema = z.object({
-    // Use coerce to automatically convert string param to number
-    id: z.coerce.number().int().positive({ message: "ID must be a positive integer" })
+  // Use coerce to automatically convert string param to number
+  id: z.coerce.number().int().positive({ message: 'ID must be a positive integer' }),
 });
 
 // Schema for updating a bank account (all fields optional)
@@ -32,7 +32,7 @@ const updateBankAccountSchema = bankAccountBaseSchema.partial(); // Makes all fi
 
 // --- Fastify Server Instance with Zod Type Provider ---
 const server: FastifyInstance = Fastify({
-    logger: true
+  logger: true,
 }).withTypeProvider<ZodTypeProvider>(); // Enable Zod validation and typing
 
 // --- API Routes ---
@@ -41,206 +41,209 @@ const API_PREFIX = '/api/bank-account';
 
 // 1. Create Bank Account
 server.post(
-    `${API_PREFIX}/create`,
-    {
-        schema: { // Define Zod schema for the request body
-            body: createBankAccountSchema
-        }
+  `${API_PREFIX}/create`,
+  {
+    schema: {
+      // Define Zod schema for the request body
+      body: createBankAccountSchema,
     },
-    async (request, reply): Promise<BankAccount> => {
-        try {
-            // request.body is now typed and validated by Zod!
-            const newAccount = await prisma.bankAccount.create({
-                data: request.body, // Pass validated body directly
-            });
-            reply.code(201);
-            return newAccount;
-        } catch (error: any) {
-            server.log.error(error);
-            if (error.code === 'P2002' && error.meta?.target?.includes('accountNumber')) {
-                reply.code(409);
-                const body = createBankAccountSchema.parse(request.body);
-                throw new Error(`Bank account with number ${body.accountNumber} already exists.`);
-            }
-            reply.code(500);
-            throw new Error('Failed to create bank account.');
-        }
+  },
+  async (request, reply): Promise<BankAccount> => {
+    try {
+      // request.body is now typed and validated by Zod!
+      const newAccount = await prisma.bankAccount.create({
+        data: request.body, // Pass validated body directly
+      });
+      reply.code(201);
+      return newAccount;
+    } catch (error: any) {
+      server.log.error(error);
+      if (error.code === 'P2002' && error.meta?.target?.includes('accountNumber')) {
+        reply.code(409);
+        const body = createBankAccountSchema.parse(request.body);
+        throw new Error(`Bank account with number ${body.accountNumber} already exists.`);
+      }
+      reply.code(500);
+      throw new Error('Failed to create bank account.');
     }
+  },
 );
 
 // 2. Update Bank Account
 server.post(
-    `${API_PREFIX}/update/:id`,
-    {
-        schema: { // Define Zod schemas for params and body
-            params: paramsSchema,
-            body: updateBankAccountSchema
-        }
+  `${API_PREFIX}/update/:id`,
+  {
+    schema: {
+      // Define Zod schemas for params and body
+      params: paramsSchema,
+      body: updateBankAccountSchema,
     },
-    async (request, reply): Promise<BankAccount> => {
-        try {
-            // request.params.id is now a validated number
-            // request.body is now a validated partial object
-            const { id } = request.params;
-            const updateData = request.body;
+  },
+  async (request, reply): Promise<BankAccount> => {
+    try {
+      // request.params.id is now a validated number
+      // request.body is now a validated partial object
+      const { id } = request.params;
+      const updateData = request.body;
 
-            // Prevent updating with an empty object
-            if (Object.keys(updateData).length === 0) {
-                reply.code(400);
-                throw new Error("Request body cannot be empty for update.");
-            }
+      // Prevent updating with an empty object
+      if (Object.keys(updateData).length === 0) {
+        reply.code(400);
+        throw new Error('Request body cannot be empty for update.');
+      }
 
-            const updatedAccount = await prisma.bankAccount.update({
-                where: { id: id }, // Use the validated numeric ID
-                data: updateData,
-            });
-            return updatedAccount;
-        } catch (error: any) {
-            server.log.error(error);
-            if (error.code === 'P2025') { // Record to update not found
-                reply.code(404);
-                throw new Error(`Bank account with ID ${request.params.id} not found.`);
-            }
-            if (error.code === 'P2002' && error.meta?.target?.includes('accountNumber')) {
-                reply.code(409);
-                // Access accountNumber safely as it's optional in update
-                const attemptedNumber = request.body.accountNumber || '(unchanged)';
-                throw new Error(`Bank account with number ${attemptedNumber} already exists.`);
-            }
-             // Handle Zod validation errors specifically if needed (though Fastify usually does)
-             if (error instanceof z.ZodError) {
-                 reply.code(400);
-                 throw new Error(`Validation Error: ${error.errors.map(e => e.message).join(', ')}`);
-             }
-            reply.code(500);
-            throw new Error('Failed to update bank account.');
-        }
+      const updatedAccount = await prisma.bankAccount.update({
+        where: { id: id }, // Use the validated numeric ID
+        data: updateData,
+      });
+      return updatedAccount;
+    } catch (error: any) {
+      server.log.error(error);
+      if (error.code === 'P2025') {
+        // Record to update not found
+        reply.code(404);
+        throw new Error(`Bank account with ID ${request.params.id} not found.`);
+      }
+      if (error.code === 'P2002' && error.meta?.target?.includes('accountNumber')) {
+        reply.code(409);
+        // Access accountNumber safely as it's optional in update
+        const attemptedNumber = request.body.accountNumber || '(unchanged)';
+        throw new Error(`Bank account with number ${attemptedNumber} already exists.`);
+      }
+      // Handle Zod validation errors specifically if needed (though Fastify usually does)
+      if (error instanceof z.ZodError) {
+        reply.code(400);
+        throw new Error(`Validation Error: ${error.errors.map((e) => e.message).join(', ')}`);
+      }
+      reply.code(500);
+      throw new Error('Failed to update bank account.');
     }
+  },
 );
 
 // 3. Delete Bank Account
 server.delete(
-    `${API_PREFIX}/delete/:id`,
-    {
-        schema: { // Define Zod schema for params
-            params: paramsSchema
-        }
+  `${API_PREFIX}/delete/:id`,
+  {
+    schema: {
+      // Define Zod schema for params
+      params: paramsSchema,
     },
-    async (request, reply): Promise<{ message: string; deletedAccount: BankAccount }> => {
-        try {
-            // request.params.id is now a validated number
-            const { id } = request.params;
+  },
+  async (request, reply): Promise<{ message: string; deletedAccount: BankAccount }> => {
+    try {
+      // request.params.id is now a validated number
+      const { id } = request.params;
 
-            const deletedAccount = await prisma.bankAccount.delete({
-                where: { id: id }, // Use the validated numeric ID
-            });
-            return { message: `Bank account with ID ${id} deleted successfully.`, deletedAccount };
-        } catch (error: any) {
-            server.log.error(error);
-            if (error.code === 'P2025') { // Record to delete not found
-                reply.code(404);
-                throw new Error(`Bank account with ID ${request.params.id} not found.`);
-            }
-             // Handle Zod validation errors
-             if (error instanceof z.ZodError) {
-                reply.code(400);
-                throw new Error(`Validation Error: ${error.errors.map(e => e.message).join(', ')}`);
-            }
-            reply.code(500);
-            throw new Error('Failed to delete bank account.');
-        }
+      const deletedAccount = await prisma.bankAccount.delete({
+        where: { id: id }, // Use the validated numeric ID
+      });
+      return { message: `Bank account with ID ${id} deleted successfully.`, deletedAccount };
+    } catch (error: any) {
+      server.log.error(error);
+      if (error.code === 'P2025') {
+        // Record to delete not found
+        reply.code(404);
+        throw new Error(`Bank account with ID ${request.params.id} not found.`);
+      }
+      // Handle Zod validation errors
+      if (error instanceof z.ZodError) {
+        reply.code(400);
+        throw new Error(`Validation Error: ${error.errors.map((e) => e.message).join(', ')}`);
+      }
+      reply.code(500);
+      throw new Error('Failed to delete bank account.');
     }
+  },
 );
 
 // 4. Get All Bank Accounts
-server.get(
-    `${API_PREFIX}/`,
-    async (request, reply): Promise<BankAccount[]> => {
-        // No input validation needed for getting all items usually
-        try {
-            const accounts = await prisma.bankAccount.findMany({
-                orderBy: { createdAt: 'desc' }
-            });
-            return accounts;
-        } catch (error: any) {
-            server.log.error(error);
-            reply.code(500);
-            throw new Error('Failed to retrieve bank accounts.');
-        }
-    }
-);
+server.get(`${API_PREFIX}/`, async (request, reply): Promise<BankAccount[]> => {
+  // No input validation needed for getting all items usually
+  try {
+    const accounts = await prisma.bankAccount.findMany({
+      orderBy: { createdAt: 'desc' },
+    });
+    return accounts;
+  } catch (error: any) {
+    server.log.error(error);
+    reply.code(500);
+    throw new Error('Failed to retrieve bank accounts.');
+  }
+});
 
 // Optional: Get Single Bank Account by ID
 server.get(
-    `${API_PREFIX}/:id`,
-    {
-        schema: { // Define Zod schema for params
-            params: paramsSchema
-        }
+  `${API_PREFIX}/:id`,
+  {
+    schema: {
+      // Define Zod schema for params
+      params: paramsSchema,
     },
-    async (request, reply): Promise<BankAccount> => {
-        try {
-             // request.params.id is now a validated number
-            const { id } = request.params;
+  },
+  async (request, reply): Promise<BankAccount> => {
+    try {
+      // request.params.id is now a validated number
+      const { id } = request.params;
 
-            const account = await prisma.bankAccount.findUnique({
-                where: { id: id }, // Use the validated numeric ID
-            });
+      const account = await prisma.bankAccount.findUnique({
+        where: { id: id }, // Use the validated numeric ID
+      });
 
-            if (!account) {
-                reply.code(404);
-                throw new Error(`Bank account with ID ${id} not found.`);
-            }
-            return account;
-        } catch (error: any) {
-             // Handle Zod validation errors (though should be caught by Fastify earlier)
-             if (error instanceof z.ZodError) {
-                reply.code(400);
-                throw new Error(`Validation Error: ${error.errors.map(e => e.message).join(', ')}`);
-             }
-             // If Prisma throws or other errors occur after validation
-             if (!reply.sent) {
-                 // Specific check for Prisma's RecordNotFound (though findUnique returns null, not throws P2025 by default)
-                 // The !account check above handles the "not found" case for findUnique
+      if (!account) {
+        reply.code(404);
+        throw new Error(`Bank account with ID ${id} not found.`);
+      }
+      return account;
+    } catch (error: any) {
+      // Handle Zod validation errors (though should be caught by Fastify earlier)
+      if (error instanceof z.ZodError) {
+        reply.code(400);
+        throw new Error(`Validation Error: ${error.errors.map((e) => e.message).join(', ')}`);
+      }
+      // If Prisma throws or other errors occur after validation
+      if (!reply.sent) {
+        // Specific check for Prisma's RecordNotFound (though findUnique returns null, not throws P2025 by default)
+        // The !account check above handles the "not found" case for findUnique
 
-                 server.log.error(error); // Log other unexpected errors
-                 reply.code(500);
-                 throw new Error('Failed to retrieve bank account.');
-             }
-             // If reply already sent (e.g., 404), just rethrow the original error
-             throw error;
-        }
+        server.log.error(error); // Log other unexpected errors
+        reply.code(500);
+        throw new Error('Failed to retrieve bank account.');
+      }
+      // If reply already sent (e.g., 404), just rethrow the original error
+      throw error;
     }
+  },
 );
 
 // --- Graceful Shutdown ---
 const gracefulShutdown = async (signal: string) => {
-    console.log(`*^! Received signal ${signal}. Shutting down...`);
-    try {
-        await server.close();
-        console.log('Fastify server closed.');
-        await prisma.$disconnect();
-        console.log('Prisma client disconnected.');
-        process.exit(0);
-    } catch (err) {
-        console.error('Error during shutdown:', err);
-        process.exit(1);
-    }
+  console.log(`*^! Received signal ${signal}. Shutting down...`);
+  try {
+    await server.close();
+    console.log('Fastify server closed.');
+    await prisma.$disconnect();
+    console.log('Prisma client disconnected.');
+    process.exit(0);
+  } catch (err) {
+    console.error('Error during shutdown:', err);
+    process.exit(1);
+  }
 };
 process.on('SIGINT', () => gracefulShutdown('SIGINT'));
 process.on('SIGTERM', () => gracefulShutdown('SIGTERM'));
 
 // --- Start Server (unchanged) ---
 const start = async () => {
-    try {
-        const host = process.env.API_HOST || '0.0.0.0';
-        const port = parseInt(process.env.API_PORT || '3000', 10);
-        await server.listen({ port, host });
-    } catch (err) {
-        server.log.error(err);
-        await prisma.$disconnect();
-        process.exit(1);
-    }
+  try {
+    const host = process.env.API_HOST || '0.0.0.0';
+    const port = Number.parseInt(process.env.API_PORT || '3000', 10);
+    await server.listen({ port, host });
+  } catch (err) {
+    server.log.error(err);
+    await prisma.$disconnect();
+    process.exit(1);
+  }
 };
 
 start();
diff --git a/src/test/accounts.test.ts b/src/test/accounts.test.ts
index 34b37e3..94aeb49 100644
--- a/src/test/accounts.test.ts
+++ b/src/test/accounts.test.ts
@@ -1,7 +1,7 @@
-import { describe, it, expect } from 'vitest';
-import { GET as listAccounts } from '../pages/api/accounts/index';
+import { describe, expect, it } from 'vitest';
 import { GET as getAccount } from '../pages/api/accounts/[id]/index';
 import { GET as listTransactions } from '../pages/api/accounts/[id]/transactions/index';
+import { GET as listAccounts } from '../pages/api/accounts/index';
 import { createMockAPIContext } from './setup';
 
 describe('Accounts API', () => {
@@ -48,7 +48,7 @@ describe('Accounts API', () => {
 
     it('should return empty array for account with no transactions', async () => {
       const response = await listTransactions(
-        createMockAPIContext({ params: { id: '999' } }) as any
+        createMockAPIContext({ params: { id: '999' } }) as any,
       );
       const transactions = await response.json();
 
diff --git a/src/test/setup.ts b/src/test/setup.ts
index 9764888..2a41165 100644
--- a/src/test/setup.ts
+++ b/src/test/setup.ts
@@ -1,6 +1,6 @@
+import type { APIContext } from 'astro';
 import { beforeEach } from 'vitest';
 import { accounts, transactions } from '../data/store';
-import type { APIContext } from 'astro';
 
 // Create a mock APIContext factory
 export function createMockAPIContext<T extends Record<string, string> = Record<string, string>>({
@@ -43,7 +43,7 @@ beforeEach(() => {
       name: 'Test Savings',
       last4: '5678',
       balance: 5000.0,
-    }
+    },
   );
 
   // Reset transactions to initial state
@@ -62,6 +62,6 @@ beforeEach(() => {
       date: '2025-04-24',
       description: 'Test Transaction 2',
       amount: 100.0,
-    }
+    },
   );
 });
diff --git a/src/test/transactions.test.ts b/src/test/transactions.test.ts
index bb5da92..ff659db 100644
--- a/src/test/transactions.test.ts
+++ b/src/test/transactions.test.ts
@@ -7,13 +7,13 @@
 // - Add load testing for API endpoints
 // - Implement test data factories
 
-import { describe, it, expect } from 'vitest';
-import { POST as createTransaction } from '../pages/api/transactions/index';
-import {
-  PUT as updateTransaction,
-  DELETE as deleteTransaction,
-} from '../pages/api/transactions/[id]/index';
+import { describe, expect, it } from 'vitest';
 import { accounts, transactions } from '../data/store';
+import {
+  DELETE as deleteTransaction,
+  PUT as updateTransaction,
+} from '../pages/api/transactions/[id]/index';
+import { POST as createTransaction } from '../pages/api/transactions/index';
 import type { Transaction } from '../types';
 import { createMockAPIContext } from './setup';
 
@@ -273,7 +273,7 @@ describe('Transactions API', () => {
       const initialCount = transactions.length;
 
       const response = await deleteTransaction(
-        createMockAPIContext({ params: { id: '1' } }) as any
+        createMockAPIContext({ params: { id: '1' } }) as any,
       );
 
       expect(response.status).toBe(204);
@@ -292,7 +292,7 @@ describe('Transactions API', () => {
 
     it('should return 404 for non-existent transaction', async () => {
       const response = await deleteTransaction(
-        createMockAPIContext({ params: { id: '999' } }) as any
+        createMockAPIContext({ params: { id: '999' } }) as any,
       );
 
       const error = await response.json();
@@ -313,7 +313,7 @@ describe('Transactions API', () => {
       transactions.push(testTransaction);
 
       const response = await deleteTransaction(
-        createMockAPIContext({ params: { id: 'test-delete' } }) as any
+        createMockAPIContext({ params: { id: 'test-delete' } }) as any,
       );
 
       const error = await response.json();