Setting sail from Ember: why we are charting a course toward React at Qonto

Florian Ellis
The Qonto Way
Published in
4 min readOct 24, 2023
Article: Setting sail from Ember: why we are charting a course toward React at Qonto, by Florian Ellis.

It was a Thursday morning, 23 March.

Fresh back from two weeks of vacation, I had a routine catch-up scheduled with Steef Janssen, the senior expert in charge of cross-cutting technical topics for our Web team at Qonto.

“Hey Steef, do you think Ember is the right technology for Qonto for the next ten years?”


Qonto has been using Ember to power its web apps since day 1:

Image: Initial commit of our main web app, qonto-js, now deployed at, in April 2016.
Initial commit of our main web app, qonto-js, now deployed at, in April 2016.

Ember has served us well. Our apps grew to 800,000 lines of code. Our 15,000 automated tests provide us with 93% coverage on our main app. We deploy to production 30 times a day. From a simple business account in 2017, Qonto has evolved into an all-in-one business finance solution, featuring invoice management, expense management and bookkeeping.

And yet, warning signals were piling up around us.

The successive editions of the State of JavaScript study showed that Ember’s popularity was declining in the community:

Graph: % of respondents who heard of Ember

Even more concerning was the dwindling appetite of developers for the framework:

Graph: Out of respondents who used Ember, % who would use it again.

We found out that LinkedIn — the largest company using Ember to power its web app — had decided to move away from it in 2022.

Pulling on that thread, we surveyed our own team on their opinion of Ember. The results were striking:

Graph: “As a front-end engineer, I see myself working with Ember in the next five to eight years whether at Qonto, or elsewhere.”

Now that’s a wake-up call.

Continuing our internal deliberations, we realized how much we could gain by moving to a more popular technology such as React. With thousands of developers contributing to its ecosystem, it can deliver technical innovations quickly and reliably. For instance, our Ember apps currently support live-reload, but not hot-reload: a change to the code triggers a full page refresh, discarding the app’s current state. With a more modern framework, we would benefit from hot-reload out-of-the-box, shortening the coding feedback loop and improving our developer experience.

As a team we pride ourselves on hiring fast — we grew over 50% in 2022 — and on keeping our team members engaged. In our last employee survey, 83% agreed that all in all, they were “very satisfied” with their job. There are a lot of ingredients in that recipe, and using the latest technologies is one of the most important. For a software engineer, frictionless tools aren’t just a convenience, they’re a necessity. They’re the finely honed knives on the restaurant countertop, allowing us to reach that state of seamless creativity and productivity.

After consolidating our research, we presented the idea to all team managers, to our Staff engineers, and then to the whole team at an all-hands meeting. That meeting will stay with me forever. The meeting chat just exploded. A few gems:

I love this announcement 🔥 Big changes are coming 😃

Pandora’s box opened.

Let the frontend library wars begin :P

Reactions were off the chart.

Now, with a few months’ hindsight, we feel like the team is united in taking on the daunting task of switching technology. Migrating 800,000 lines of code is a monumental project, which we’ll need to complete while still delivering new features at a high pace. The road will be fraught with pitfalls, but we’re leaving ourselves the time to prepare it thoroughly, carefully designing the target architecture and the migration strategy.

However, I can’t stress enough how much Ember and its community have propelled Qonto forward over the years since our launch. Thanks to Ember and its ecosystem, we were able to build a top-notch finance management solution serving the needs of 400,000 European businesses. We’ll still be using Ember for the coming few years, as this migration won’t happen overnight. And we’ll always be grateful to all Ember contributors for allowing us to build and scale Qonto’s web apps.

Qonto’s Web team will grow by 30% in 2024. We need excellent software engineers to help us deliver even more value to our customers, while undertaking this herculean migration simultaneously. We also need first-rate managers who will create the best environment for engineers to produce, learn and thrive. If you feel up to the challenge, check out the open positions in our Web team!

About Qonto

Qonto is a finance solution designed for SMEs and freelancers founded in 2016 by Steve Anavi and Alexandre Prot. Since our launch in July 2017, Qonto has made business financing easy for more than 350,000 companies.

Business owners save time thanks to Qonto’s streamlined account set-up, an intuitive day-to-day user experience with unlimited transaction history, accounting exports, and a practical expense management feature.

They stay in control while being able to give their teams more autonomy via real-time notifications and a user-rights management system.

They benefit from improved cash-flow visibility by means of smart dashboards, transaction auto-tagging, and cash-flow monitoring tools.

They also enjoy stellar customer support at a fair and transparent price.

Interested in joining a challenging and game-changing company? Consult our job offers!