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Eva Yi Zheng
I like to write about everything!

React.js is a handful, but that’s why cheat sheets are appreciated.


MDN does a great job explaining what a Promise is.

The Promise object represents the eventual completion (or failure) of an asynchronous operation and its resulting value.

I got into Citibank in November 2018, just as the first semester of my senior year in college was about to end. I was promoted to the mortgage department in August 2020 and then left January 2021 for Flatiron School.

Here’s what I have learned. Some seem to be common sense but I’ve realized that many of my previous clients did not know about online banking.

Account Opening/Online Banking

Many people spend so much time waiting in line just to open a basic account (as in there are no specific requirements from court). It is way easier to open an account online. …

I was a broke high school student when I first stepped into the world of skincare. I have to apologize to my skin for:

  • not using sunscreen
  • not washing my skin properly when I was younger
  • using highly fragranced products
  • not using sunscreen

I will definitely dedicate an article on the DON’Ts of skincare. Oh, the regrets of my younger days.

(Each category will only have one product.)

Makeup Cleanser

Papaya Sorbet Enzyme Cleansing Balm $32

Can you imagine accidentally saving bad data into your database? If bad data were to get into your database, you could add additional logic into your controllers to handle them. But what if we could somehow handle that before an object is created?

Along with validations, using callbacks will prevent bad data from being inserted into your database.

What is a callback?

A callback is a method that gets called during an object’s specific moment in its lifecycle. An object’s lifecycle is from its creation to its destruction In-between the creation and destruction of an object will be the READ and UPDATE moments.

Step 1


Part 2! A list of 3 of the remaining 6 credit cards that I currently use, although there are some that I do regret signing up for. Only 3 cards just to keep this article relatively short.

Wells Fargo Propel

Flatiron has Javascript as part of its curriculum but I thought it would be fun to try to teach it to myself to see how well I can do it after having learned a bit of Ruby. Javascript, along with CSS and HTML, surrounds us every day, so it’s quite a handy language to learn and understand. I do encourage everyone to pick up some basic coding skills/knowledge so let’s start with the basics!

Hello World — Strings

As it is a tradition in all coding languages to teach how to print “Hello World” as everyone’s first line, let’s do that first! For anyone…

I love writing articles about coding but another interest and passion of mine is credit cards. Full disclosure: I am not a licensed financial advisor. I just really love credit cards and I love talking about them. I truly believe that if used correctly, it can benefit everyone.

Let’s get right to it!

What is a credit score?

Think back to the Black Mirror episode, Nosedive, in which everyone’s social score was open for viewing. Although a credit score is not as public, it does affect one’s ability to obtain loans at a reasonably low interest rate.

Some might think, Oh, I’ll never need a…

I love building! Whether it be Nanoblocks, Metal Earth models, or programs, I just love building. I was recently introduced to the Sinatra library for Ruby, and it is definitely mind-blowing.

For anyone new to coding (such as myself), a library is a set of code that was made by very, very generous coders. Libraries make our lives easier because we won’t have to worry about re-defining and repeating the basic codes that exist in almost every app. Sinatra is a library for building basic websites.

However, just being given a library is definitely a risky move. For one thing…

Phase 2 of the Flatiron journey slowly unfolds and I’m hit with SQL. I was so excited to see it on the curriculum but when I looked at the first lesson, I already wanted to exit out of the browser.

So I was just staring at the page and the page was staring back at me, and no progress was made. If you’re a newbie like me, you’ve probably only seen it in job postings and have no idea what SQL is or what it does.

Let’s slowly unfold! (Flatiron uses the SQLite data management system so the commands will…

Eva Yi Zheng

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