Intern Spotlight: Kevin Cheng (Part Two) – From Full-Stack Owner to End-to-End Shipper

Eight months ago, Kevin Cheng walked into Yolando on his first day expecting to work on BirdseyePost, but instead came in just as we were putting some finishing touches on releasing Yolando. We wrote about his first four months back in December: how he went from a backend beginner to a full-stack owner, shipping his first features into production alongside our team of senior engineers.

Today, Kevin's University of Waterloo Co-op has come to an end. And the Kevin that joined in 2025 during his finished his first co-op, has completely leveled up now with Super Mushroom 🍄 (IYKYK) strength.

Over the past four months, he's owned Yolando's self-serve billing flow end-to-end, shipped full features from design doc to deploy, and watched the product evolve from an early-stage idea into a real, usable platform that customers can onboard themselves into. Where the first half of his University of Waterloo Co-op was about ramping up, the second half was about shipping at full speed.

Here's what closing out eight months at Yolando looked like:

From Idea to Fully-Fledged Product

We asked Kevin to describe the arc of his eight months, and he doesn't talk about individual tasks. He talks about watching a product come to life.

"Being here eight months at Yolando, I've really seen it grow from basically pretty much an idea all the way to a fully-fledged product. I describe it as a high-growth and very high-ownership co-op experience."

That ownership showed up at every layer of the stack.

"I got to learn the product through how the idea came to be, then working on the initial designs, just having something to show our users, and then eventually building out the fully fleshed-out product from the back end all the way to all those small details on the front end."

For most co-op's, that's a rare trajectory. Usually they're experience is showing up to work on a more mature codebase and really only touch one slice of it. Kevin got to help shape Yolando end-to-end.

The Billing Project: A Full-Stack Build from Scratch

When Kevin talks about his favorite project from this term, one stands out: the Yolando's self-serve billing flow enabled by Stripe.

"We wanted to introduce a way for our users to self-serve on our product. I redesigned the full onboarding flow to include the billing process using Stripe integration, and then allowing skip payment for our employees so that when we have customers we're walking through the onboarding process, we're still able to quickly set up accounts and get them onboarded."

This wasn't a small feature. It stretched from design document to Stripe configuration to the back-end and front-end logic that had to cleanly process payments and move users through the flow.

"I learned a lot, from the design document all the way up to setting everything up on Stripe, and then working the back end and front end together to control the logic and process those payments, and smoothly move the user through the billing process."

A self-serve billing flow is one of the most important things any SaaS product has, and Kevin built Yolando's.

The Biggest Surprise: How Fast Yolando Ships Its Products

At his previous co-ops, Kevin got used to a slower rhythm, multiple teams, multiple approvals, waiting days or weeks for simple changes to land. At Yolando, that pattern flipped completely.

"At my previous co-ops, things often moved slower, often due to various teams that needed to review and approve. It wasn't uncommon to have three or more teams, involved to move work along. I remember trying to write a migration for a very simple change in a past co-op. It was just a simple additional field of text, and our team needed to connect with various database optimization teams. It wasn't the same environment that enabled me to work with my own direct team, and us efficiently shipping products for users."

At Yolando, the work loop is tight enough that a migration can go from idea to production in as little time as an hour.

"At Yolando, I'm able to write my migration, test it, make a pull request, and someone on the back-end team would approve it or leave a comment. Done. I was able to quickly deploy, and the work would be out the next release."

That speed is only possible because the team trusts each other to ship quality work. Kevin earned that trust, and then got to move at the pace it unlocked.

The Hardest Part: Building Before the Thing Was Built

Kevin was honest about what was hard, especially early on.

"When I started, the Yolando project was still in very early stages. Understanding what we were building was a little abstract at the start. We wanted to show a dashboard, visibility, content generation, and how that would all work together to create a product, but at the start, there wasn't really anything to build off of. It was kind of a new sprouting seed."

Building a product before it fully exists is a different kind of problem than extending an existing one. Kevin handled it the way the team handles most things: by collaborating closely with whoever was closest to the problem.

"Working on the front end, it was a lot of talking with Kevin and with Corey to go through designs and figure out what the best way to show all this data was."

There was also the challenge of navigating legacy code that had been ported over from older projects during the early push to build fast.

"We had ported over a lot of old repositories from BirdseyePost. There was a lot of code that wasn't used for Yolando, but because we were copying over repositories, some of it was in places that weren't being used. It was a little difficult parsing through all of the code to understand what was actually being used versus what was legacy code that needed to be removed."

The Skill He's Taking With Him: Shipping End-to-End

Kevin's previous co-ops gave him pieces of the puzzle, a checkout component here, a disclaimer banner there. Yolando gave him the whole thing.

"Technical-wise, the biggest skill I've learned is shipping an end-to-end product. I never really got to do that in my previous co-ops. It was very small features; like, we were going to design this checkout component, so you'd work on some of the fields, or there's this disclaimer we need to add at the bottom and the logic for when to show it. Small components."

"Here, I was able to ship full features. The learning process of going from a design document and ideas and researching what the best way to do that is, then actually implementing the feature. Then collect feedback on how resilient or how easy to understand it was for the user. That was a very good learning experience for me. I was able to really understand how we can build a whole feature from start to finish with the best design and software engineering practices."

That's the skill every engineer eventually needs and few co-ops actually teach. Kevin leaves Yolando with it.

The Team He'll Miss

Ask Kevin what he'll miss most, and he doesn't hesitate. It's the people.

"Kevin a senior engineer on the Yolando team, has been a great help to me he's the front-end engineer. He's really taught me a lot. We've discussed a lot about the features we were building and how to approach such a fast-moving project. At the start, when designs were constantly changing and the back end was already complete and we wanted to ship the feature out, Kevin and I would discuss ways to mockup a design that looked usable, something the user would enjoy using, that let us work fast."

He was just as generous with the rest of the team.

"On the back end, Sarth and Shardul have been a great help helping me understand Pydantic ORM models, since I hadn't actually worked with the libraries we use. I used to use Java at my previous co-ops, and a little bit of Python, but not to the extent here. Learning a lot about how migrations worked here, how we do a lot of the AI model stuff, how the back-end logic works—it was wonderful."

And on the product side:

"Corey, you've been an amazing project manager. You helped me a lot to prioritize tasks and gave me good feedback on design. It's been wonderful working with you and Kulin."

This is the kind of team that makes interns want to extend their co-ops. Kevin already did that once. Closing out the full eight months, it's clear why.

Fast But Extremely Fruitful

We asked Kevin to sum up his full Yolando experience in one sentence. His answer was immediate:

"Fast but extremely fruitful. We learned a lot. I was able to work with the team and really enjoyed the connections I made here."

That's the whole co-op in six words.

Thanks, Kevin

Kevin joined Yolando when it was still an idea. He leaves with the product shipped, a self-serve billing flow running in production, and a full-stack skill set that most engineers don't have at this stage of their career.

It's hard to imagine Yolando without him — he's been here since the start. We'll miss him. And we can't wait to see what he builds next.

We also want to thank Fabian 🙏

In addition to Kevin's amazing contributions to Yolando, we were fortunate to also have Fabian on our team for the last four months as well. Another amazing University of Waterloo student. To read about his experience with us during his internship, checkout his interview here.

Interested in joining the team? If you're looking for a co-op where you'll own real features, ship end-to-end to production, and work alongside people who move fast together, reach out to us at info@yolando.com.