Roasting My First JavaScript App

It’s time I look back at one of my very first JavaScript work and roast it.

It was 2014, I had recently finished JavaScript and JQuery lessons from Codecademy. It was about time I build something with my knowledge.

At that time I didn’t know what actually JQuery was. I thought it’s another language like JS. Now I know well that, JQuery is a library which goes on top of JavaScript. It makes writing code a little bit easier.

An overview of what I am going to build:


There is a mobile payment service in Bangladesh called Bkash. You can use the service to pay friends. They charge a % for everytime you want to cash out from your wallet.

The idea was simple,

  1. Have a text field so people can input an amount
  2. Click on the button to calculate the result
  3. The fee amount will show up

I could not sleep the previous night. So I got up to my computer with enthusiasm. I built the logic first.

While trying to work on it, I learned the hard way: following a tutorial is easy but building something on my own doesn’t always behave the same way.

The JavaScript

Looking at my code, I rush coded a lot. I did not commented the code, I didn’t even used semantic variable names.

Variable $b should have been called ‘balance’.

$c should have been ‘change’.

I also didn’t added a class or ID for the input button text, which would’ve make my life a bit more easier.

So you see all the code is a mess and harder to follow through.

The conditional logic tree was the hardest part.

It took me more than an hour to create the simple calculation to work. At the time of building the calculator, Bkash had a different fee structure.

Their fee % varies on the amount you are cashing out.

So I had to write a long set of conditions to fit the fee structure.

It was a really long (6-8) steps of else if codes.

It was a nightmare to make this work. So after I was done, I could display both a smaller amount and a larger amount with the correct fee.

New Fee Structure

Right after I implemented the cumbersome fee, I did a lookup online and found that Bkash now has a simplified fee structure.

What you know, they now have 1.85% flat fee for any amount you wanna cash out.

Are you kidding me?

If I had known this earlier, it would have saved me a lot of trouble.

Anyways, I implemented the new fee structure.

After a few tweaks and checking my code part was ready.


The site has just a single html page for the view. It was the first time I coded a page without the help of Bootstrap framework. At the time I did not know how to create a container in the middle so I used a table markup.

A table really?

Look, I also invented a new html tag called the <wrapper> wow!

Other than these rookie mistakes, the final design was good. It also had Facebook open graph tags which looked nice when I shared on social media.

I also registered a free domain name to host it.

I was happy and proud to share my work. Overall it was a good first project.

You can have a look at the working version here and the source code on Github.