Serverless Expense Tracker

Overview

The Serverless Expense Management Platform is a cloud-native web application designed to help users track and manage their expenses. The application uses AWS serverless technologies to provide a scalable, cost-efficient backend while delivering a fast and responsive frontend. Instead of traditional servers, the system relies on event-driven functions, managed authentication, and NoSQL storage to handle user data and transactions.

Problem

Many personal finance applications rely on centralized servers that require continuous maintenance and scaling. For small applications or independent developers, managing infrastructure can increase cost and complexity. The challenge was to build an expense management platform that could scale automatically while minimizing operational overhead.

Solution

This project uses AWS serverless services to remove the need for traditional backend servers. API Gateway routes requests to AWS Lambda functions that process business logic, while DynamoDB stores expense data efficiently. AWS Cognito manages secure authentication and user identity. Static frontend assets are hosted in Amazon S3 and delivered globally through CloudFront CDN.

Key Features

• Secure user authentication using AWS Cognito
• Add, update, and delete expense records
• RESTful APIs powered by AWS Lambda and API Gateway
• NoSQL data storage using DynamoDB
• Global content delivery with CloudFront CDN
• Fully serverless architecture for automatic scaling

Tech Stack

System Architecture

The application follows a serverless architecture where frontend requests are routed through API Gateway, which triggers AWS Lambda functions. These functions process the request and interact with DynamoDB for storing and retrieving expense data. User authentication and authorization are handled by AWS Cognito, while CloudFront and S3 deliver the frontend globally.

How It Works

1. User logs into the application using AWS Cognito.
2. The frontend sends requests to API Gateway endpoints.
3. API Gateway triggers AWS Lambda functions.
4. Lambda processes the request and interacts with DynamoDB.
5. The response is returned to the frontend with updated expense data.

Demo

Challenges

• Designing an efficient DynamoDB schema for expense queries
• Managing secure authentication and token validation
• Handling stateless Lambda execution environments
• Structuring API Gateway routes for scalable backend services