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I’ve always been afraid of RegEx. When I first started learning code, I viewed RegEx like an alien language. It was a bunch characters put together to do power things within code. Now that I’ve been coding for about a year now, I figure it’s time to learn and memorize some of the basics with RegEx.

What is RegExp?

RegEx is short hard notation for Regular Expression, which is a sequence of characters and form a search pattern. It can be used to search or search and replace, kind of like using CTRL-F for the “find” option of a document. The expression can…

npm vs yarn — credit: Rising Stack Blog

I’ve been recently working with some companies on technical challenges and projects where they’ve used different package managers than I’m used to. Package managers are used to help manage a project’s dependencies, which is a piece of code that is required for a project to work. As projects start to grow, we need help to include, remove, and update code within them, which is the purpose of the package managers. During my time at Flatiron, we typically used npm, but recently I’ve been using yarn. …

Fibonacci Sequence!

For the past month or so, I’ve been focusing on my vanilla JavaScript skills through JavaScript30 (view my progress on my website!). Because of this, I’ve been neglecting on algorithms, so I decided to jump back into it. I’ve been working through my Udemy course with Stephen Grider (which is super awesome and highly recommended) and I was very intrigued by one of the lessons about the Fibonacci sequence. It’s definitely a classic interview question, but upon my first try, I was only able to get one type of solution down. …

For the past couple of days, I’ve been working on enhancing my vanilla JavaScript. I’ve been practicing using tutorials from, which is a free 30-day coding challenge that builds 30 different projects within 30 days. It uses no frameworks, compliers, libraries, or boilerplates. While I’m currently on Day 5, I’ve learned plenty of new concepts and ways of tackling certain topics. One concept that stuck with me was the lesson on CSS variables and using JavaScript to manipulate them.

CSS Variables

CSS variables, also known as custom properties, are entities that contain specific values that can be used throughout a document…

Pinky swears are never meant to be broken

While I was at Flatiron School, something that was always confusing my was asynchronous Javascript. I always had a hard time working with the data and on a recent take home assessment, I was completely destroyed by this question. Concept wise, I’ve always understood that asynchronous functions are functions that are running, but do not hold up the rest of the program. Meaning, while one function is still processing, another function would still be able to run while that first one is still going. Examples of this are making requests/fetches to servers. …

Introduction to Maps with Javascript

Objects are one of Javascript’s data types. They are used to store various keyed collections and more complex entities. With this capability, they are probably one of the most important data types as they form modern building blocks. They are more complex because they can contain any combination of primitive data types, such as Number, String, Boolean, etc, as well as other reference data types (like other objects). Objects can be defined as an unordered collection of related data in the form of “key-value pairs.” With the introduction of ES6, we were given the option of the Map object. Maps…

Redux logo consisting of three swirling lines on the left and the word Redux on the right
Redux logo consisting of three swirling lines on the left and the word Redux on the right
Redux: State Management System

React Hooks were introduced to React with the v16.8 release in Feb 2019. Before the release, there were features that were exclusive to class components. With Hooks, functional components now allow the use of state and other React features within them. Hooks were also introduced to be able to reuse stateful logic between components, to simplify complex components that were hard to understand, and to expand features within functional components since classes were confusing to people and machines. In June 2019, React Redux v7.1 was released in order to incorporate Hooks.

Set Up Redux

The setup of Redux will be exactly the same…

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Data Structures are some of the most fundamental aspects when it comes to computer science. These structures are tools which are used to store data in a computer in a way that is used efficiently. There are many different types of structures, but this post will be focused on Stacks & Queues. These are both linear data structures that are pretty similar, but have a few unique principles that belong to each type.

Time for Part 2

Alright, part 2 of the sorting algorithms I’m going through. If you missed part 1, read my blog here! In the last blog, I reviewed selection, bubble, and insertion sorting algorithms. All of them required nested loops, which gave them all an O(n²) time complexity. For this one, we’ll be going over ones that are a little better with time complexity, such as O(n log n), which are better for larger datasets.


I made it! I graduated from Flatiron School’s Immersive Software Engineering Program last month. Hooray! Now that time has passed, it’s time to focus on the job search. With the job search, comes the interviews, which are both technical and non-technical. Because of this, I’ve decided to dedicate some of my next few blogs on data structures and algorithms. While we were briefly exposed to this at Flatiron, we didn’t practice it too much. So I’ve decided to write blogs about them.

First up, sorting algorithms (in Javascript)!

What is a Sorting Algorithm? Why is it Important?

Scott Espinosa

Software Engineer based out of the San Francisco Bay Area. Flatiron School graduate with 8+ years background in healthcare.

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