What is DX (Developer Experience) and how to improve it

code.dev + resend

git commit -m 'first commit'

Welcoming Gusttavo Castro, our new Developer Experience Engineer


**Gusttavo Castro** is a software engineer who loves both front-end and back-end.

Before joining Code.dev, he worked at Adaptworks, where he helped build their training platform for SAFe and Agile methodologies.

He also explored how gamification can help people learn data structures and algorithms (DSA) — the topic of his undergrad thesis.

## More about Gusttavo

**How did you get into software?**
Looking back, I was closer to it than I remembered. My first experience with programming was in school, during a Brazilian Informatics Olympiad (OBI). Total disaster. The code didn’t even compile. I froze. But that moment — without realizing — was the start of something.

A few years later, Gusttavo joined Etec during high school. Naturally curious, he was already tinkering with computers on his own. And pretty quickly, he realized he didn’t just like it — he was good at it. So good that, after graduating, he was hired by one of his own teachers to work at Adaptworks.

**Why Code.dev?**

As an engineer, I’m happiest when the stuff I build makes someone’s day easier — and Code.dev lets me do exactly that. I’ve been following the company since the beginning and was always impressed by the polish and care that goes into it.

When it was time to take the next step in my career, Code.dev had everything I was looking for: a product that matters, a culture that treats craftsmanship seriously, and teammates who care about the small details as much as the big picture.

**Where do you find #inspiration?**

Music. There’s something magical about how a song can shift my mood or spark an idea out of nowhere.

**If you weren’t coding, what would you be doing?**

I’ve always been fascinated by design, so I’d probably be working on interface design or something visual.

And if that didn’t work out — I’ve always wondered what it’s like to be a pro DJ and play at TomorrowLand.

**What does your workspace/home screen look like?**

Snoopy is my all-time favorite cartoon, so I like to keep a few Snoopy touches around me!

![Gusttavo's desktop](/static/images/workspace.png)

**Favorite tool?**

I love taking notes with [Obsidian](https://obsidian.md). It’s a simple yet powerful app that helps me organize my thoughts and study better.

Plus, the brain-style graph view is just awesome.

![My neurons](/static/images/obsidian.png)

**Favorite keyboard shortcut?**

Alt + Space. I use it to trigger Raycast and basically do anything.

**Favorite place to visit?**

São Paulo, Brazil.

It’s where I’m from, where my family lives, and where my journey with programming began. I visit whenever I can!

**Any advice for ambitious software engineers?**

Read code.

We usually spend most of our time writing code, but reading code is one of the best ways to grow as a developer.

Reading exposes you to different architectural patterns you might not come up with on your own — and broadens your perspective. Start with well-known open-source codebases and pay attention to how experienced devs structure complex solutions.


We're thrilled to share the news that Gustavo Castro is joining code.dev.


## Rethinking how devs talk via email

We’ve been rethinking how developers communicate through email — and Resend turned out to be the perfect partner for the job.

To kick things off right, the welcome emails for our waitlist are being carefully reviewed and improved by the Resend team — easily one of the best in the game.

We’re using the waitlist data from Code.dev not just to validate the product, but to really understand who’s joining our community and why.

## What’s Code.dev again?

Code.dev is a DSA app built by devs, for devs. Think of it as a next-gen Leetcode — but faster, more fun, and fully gamified.

It’s been five weeks since the first idea hit the whiteboard. Since then, we’ve had X people join the waitlist. Our open-source project, Icebit ID, is also picking up steam, now with X stars on GitHub.

## Why Resend?

We’ve always seen Resend as the best email API for developers building modern apps. Integration was dead simple — in minutes, we had transactional emails flowing with full consistency and visibility.

React Email sealed the deal. Writing emails with components and previewing everything locally has been a game-changer for our team.

Resend delivers (literally) a dev-first experience — no hacks, no broken SPF records, no clunky GUIs... looking at you, Sendgrid.

## What we’ve learned

Putting the project out there — even with just a landing page and a waitlist — was one of our best decisions. It gave us real feedback, real metrics, and a much clearer view of the community’s interest.

Using Resend from day one gave us peace of mind to scale up our comms. We’re building a solid foundation for newsletters, onboarding emails, and real-time alerts — without worrying about spam filters or misconfigured DNS.

With Resend in the mix, we’re taking our marketing and analytics game to infinity and beyond.

Now we’re doubling down on three pillars:

1. **Newsletter**
2. **Marketing**
3. **Onboarding**

This is just the beginning — and we’re hyped to share every step of the journey with you.

## What this means for Code.dev

Code.dev is growing fast — like, *really* fast.

Demand’s been off the charts, and we’re now sending thousands of emails every single day.

Scaling our communication stack became a top priority — and we couldn’t be more excited to have Resend in our corner.

We’re just getting started.


We're excited to announce that code.dev is now backed by Resend.

Stories. Updates. Guides.

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Welcoming Gusttavo Castro, our new Developer Experience Engineer

code.dev + resend

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