Who’s building ULTIMATE? Bruno Wozniak - Software engineer

With the launch of the ULTIMATE DeFi wallet around the corner, we’d like to highlight our star-studded team, and reveal the experiences that have shaped their design decisions at Ultimate.

Bruno Wozniak — Software engineer
Prev. Lead software engineer @ Revolut

Bruno, how do you think about building our product?
Well, you can either execute on a grand vision where you try to be “right from the start”, or you can be more open minded, try out different things, and find out what users like. The 2nd choice is the easier path, but it can corner you into offering an experience that is locally optimized but not the most coherent overall.

You were at Revolut before working on Ultimate?
Yes, at Revolut I built a company-wide data platform and collected telemetry data to understand usage patterns. It was also really useful to learn how to make large teams of engineers work well together. The challenges are very different between “just coding” and engineering software at scale.

So you work on the backend of the Ultimate app? Don’t wallets just exist on the blockchain?
The mobile wallet is the keeper of the keys, and we handle a lot of the complexity on the backend side. Having a backend allows us to iterate very quickly — we can fix little bugs without releasing a new version of the app. It also allows us to unify Ethereum and Solana support in a single API that is easier for our mobile developers to work with. It also gives us the speed advantage — we can cache data in the backend and avoid constantly fetching data from the blockchain.

Do our users need to worry about our backend falling over? Is that a risk?
With minor outages, the user might notice slowdowns or missing transaction history. However, in the unlikely event where our app becomes totally unusable, or even if the company ceased to exist, the user could take their keys and access their account from another wallet app. That’s the beauty of a self-custody wallet. Because users can take their business elsewhere, a failure would be worse for us than the user.

What about Ultimate are you most proud of?
I’m happy that the app feels fast. We’ve used performance data to optimize the slow parts — so things are only as slow as they absolutely need to be.

What’s been hardest to build on Ultimate?
The “activities” a.k.a. the transaction history. It requires architecture in the background to contextualize raw blockchain transactions as a swap, NFT purchase, etc, but this means the phone doesn’t have to do much computing and the user doesn’t have to wait.

Anything else to ask you?
Favorite beer? Just kidding, we’re all professionals here, we don’t drink, we only work.

How about a favorite coffee?
I usually go for a filter, the more sour Ethiopian kind.

Thanks for your time Bruno!