Create your Net Worth Tracker with Kotlin

Tracking your Net Worth is the best way to stay aware of your personal financial situation. It doesn’t have to be boring or complicated…

If you know how to code, you can now make it fun!

What is the Net Worth and why should you keep track of it?

Your net worth is the total value of your assets (cash, investments, house value…) minus the value of your liabilities (i.e. debts: loans, mortgage, credit card balance…). By knowing at each time how much you own, you can plan goals and see how close you are to achieving them.

Tracking your net worth can be as simple as listing all your assets, your liabilities, and making some additions and subtractions. But what if you own assets in different currencies? Or what if you own stocks and don’t want to go manually fetch their value? This is when building your own tracker will help you!

Contents

1. Your local development environment
2. Your first net worth tracker
3. Displaying table reports in the terminal
4. Adding metadata to accounts
5. Building a better command-line application
6. Accounts in different currencies
7. Dependency injection and global configuration
8. Stocks and cryptocurrencies
9. Resilient API calls with a cache and a retry mechanism
10. Reports in the web browser

Why should you read the book?

• Because you have your money in different places (bank accounts, stocks, real estate, art…) and would like to track how much these places carry over time.
• Because Excel is not flexible enough for you, and third-party services are not reliable enough.
• Because you are looking for a fun project to experiment with Kotlin and apply powerful design patterns.

With this book you’ll learn how to:

• Create the right data model using Kotlin’s expressivity to handle your accounts, their specificities, and their value over time.
• Present the evolution of your personal finances in pretty ways, in the console, and in a web page.
• Call useful APIs to convert currencies and get stock values to avoid as much manual process as possible.

Why Kotlin? What if you don’t know the language?

Kotlin is a modern language, very easy to learn, that lets you write very expressive code. Using it, you can focus on the business logic you want to implement, rather than the technical details such as dealing with memory.

If you have never used it but already know another language (e.g. Java, JavaScript, Ruby…), here is a secret for you: I didn’t know Kotlin before I started creating my net worth tracker 🤫! It was a great project to learn the basics, and I was never blocked by language technicalities.

Hi! I’m Sebastien Castiel 👋

I’m a French developer expatriated in Montreal.

I’m passionate about personal finance. I work for a Canadian fintech company, and I have used several languages professionally for several years now.

What if I don’t like what I bought?

If you are not satisfied with the book, I offer you a 30-day money-back guarantee, no question asked.

Just shoot me an email at sebastien@castiel.me.