Before diving into the Q&A, read the full case study to see exactly how Elli moved from shared legacy infrastructure to Bitrise, cutting build times by 89% and reclaiming 2 developer days per month, and what it means for Volkswagen Group’s EV strategy in Europe.
Europe’s transition to electric vehicles (EVs) is gearing up and one car maker is leading the charge. The Volkswagen Group recently eclipsed Tesla as Europe’s top EV maker, with deliveries surging a stunning 89% year on year to 347,900 vehicles.
But it’s too early to celebrate yet, with the EU’s 2035 ban on new petrol and diesel cars looming large, keeping adoption moving is crucial. That’s where Elli, Volkswagen Group’s charging and energy company, comes in. Its two consumer-facing apps give drivers real-time updates on charging points and energy sources, keeping them connected at home and on the road. This makes it central to Volkswagen Group’s EV strategy, and ultimately Europe’s EV future.
To keep pace with rising expectations, Elli decided to overhaul its mobile development to deliver new functionality to its consumers fast. This meant switching from legacy infrastructure that was holding it back to mobile-first CI/CD with Bitrise.
To learn more about their journey with Bitrise and what’s next on the horizon, we sat down with Ganesh Bala Subramanian, Engineering Team Lead to find out more.
[Q1] Can you tell us more about Elli and what the company's top focus is at the moment?
[Ganesh] Elli is a brand of the Volkswagen Group and is all about empowering electric life. Our mission is to support the transition to electric vehicles (EVs) across Europe which means everything from charging points at home and on the road. Energy is also a critical part of the business. As part of this, we’ve also started focusing on the broader transition from combustion vehicles to EVs. That shift hasn’t happened as quickly as governments expected so there’s now real pressure to accelerate it.
As a result, a large part of our focus is on business fleets, which represent a significant share of vehicles on the road today. If we can transition these fleets to EVs, it would make a huge difference in reducing the ratio of combustion to electric vehicles. That's one of our main points of focus, and where a major part of our work is centered.
[Q2] How does your mobile strategy support your focus on EV adoption in Europe?
[Ganesh] Our apps have always been our primary interface with customers, helping them manage home charging, find charging stations on the go, and track spending. On top of this, we also offer our own hardware that customers can use to interface with the app to control their chargers, set limits, run diagnostics, and monitor usage.
Currently we have two main apps. The first is our flagship app, bringing all EV and energy solutions into one place. We have multiple teams contributing just to this one application. The second is a smaller companion app for Volkswagen, Skoda, and CUPRA EV drivers that integrates seamlessly with their EVs to easily manage their smart charging at home with our range of branded smart chargers.
[Q3] What spurred you on to explore a new mobile development solution at Elli?
[Ganesh] We use Azure DevOps as our all-in-one tool for project management, code hosting, and infrastructure for both apps and backend services. When I joined, we were still using Azure DevOps for mobile CI/CD as well. But this meant sharing hardware, which meant our builds were very slow and we had to rely on software versions that were always a couple of releases out of date. We had no real control over our build environment, which became a real challenge day to day.
Our priority was to keep Azure DevOps pipelines, as they were well integrated into our ecosystem, but define our own stack behind it. For Android, we tried virtual machines on Google Cloud with Docker. For iOS, we experimented with three Mac Minis in the office connected to Azure pipelines. But ultimately both setups came with a number of challenges and compromises and ultimately weren’t sustainable.
We also explored third-party cloud solutions, but again none of them met all our needs. If anything they added additional overhead as we would need to maintain and troubleshoot the machines ourselves, so that wasn’t going to work. Personally I enjoy getting involved in the wider DevOps work but not everyone on the team enjoys this aspect, they want to be able to focus 100% on mobile development.
So overall we wanted to find a solution that would reduce the time and effort we had to spend on CI/CD so we could improve our productivity and free up more time for higher value work. Ultimately, that’s what led us to Bitrise.
[Q4] What would you say were the biggest challenges you faced day to day at that point?
[Ganesh] The biggest challenge was maintenance and keeping everything up to date. It wasn’t just managing different machines, we also had to factor in using Terraform to define how everything was set up which added another layer of complexity. Getting onboarded onto technologies you don’t use daily was a lot of overhead and added to the team’s mental load. If you had to switch context between mobile development and troubleshooting a failed build, that already felt like a failure because it took our focus away from delivering to users.
On top of that, builds were very slow because we had limited resources. At the time, we had close to 20 developers all trying to build on three Mac Minis. There’s only so much you can parallelize, and it wasn’t as simple as adding 10 more Mac Minis and calling it a day. We wanted a setup that could expand or contract as demand required, and that’s what was missing.
[Q5] How did you first discover Bitrise?
[Ganesh] I had already used Bitrise in the past. Before joining Elli, I worked at SIXT, and that’s where we first came across Bitrise. That was around 2016–2017, when mobile DevOps was still quite new. I was involved in the proof of concept there and got to know the platform well. I had a really good experience working with Bitrise and the team and the same goes for a couple of my colleagues who also came from SIXT, one even took part in a Bitrise case study back then.
Nonetheless, we did a thorough evaluation of all the options on the market. We couldn't just go to procurement and say "get us Bitrise." We had to explain why and make a fair comparison. So, we looked in detail at CircleCI, Bitrise, BuddyBuild, and a few others.
[Q6] What ultimately convinced you that Bitrise was the right choice?
[Ganesh] Bitrise was the only company willing to work with us to find a solution for integrating Azure DevOps into our mobile workflows, and that really stood out. When we put the challenge to the team and asked how we could make it work, they didn’t hesitate.
Basically they took an open-source plugin we’d found and, within a couple of weeks, had modified it and connected our Azure DevOps to Bitrise. All during our proof of concept. I was super impressed at how quickly it came together. No other vendor was willing to do that for us without some kind of commitment, and that said a lot. It 100% swayed our decision to go with Bitrise.
[Q7] How was the migration and onboarding experience?
[Ganesh] The migration went really smoothly. We planned it carefully and to ensure we had minimal disruption we migrated most of our build processes into Fastlane, which acted as a middle layer between our Azure set up and Bitrise. That way, when we switched platforms, it was simply a matter of plugging Fastlane into Bitrise rather than rewriting everything from scratch.
Bitrise’s support made a huge difference throughout the whole process. We had a dedicated Slack channel, and direct access to solution engineers which was invaluable.
[Q8] Was the impact of Bitrise immediately noticeable to you and your team?
[Ganesh] 110 percent. One of the first things we noticed was that we didn’t have to think about CI/CD anymore, it just worked. We also didn’t have to navigate unfamiliar technology or force the team to work with YAML files for configuration. We could simply go into Bitrise and set everything up. Right away it empowered our developers to do exactly what they needed without going through the convoluted processes we had before. That value was immediate.
The other big improvement was build time. At the time, we had three different applications, all of which had to be built because they were white labels. As you can imagine, that took some time, and in our old setup we couldn’t parallelize builds as much as we wanted.
With Bitrise, we could do that right away and cut build times dramatically, from up to an hour and a half in the worst case, when we were dependent on shared virtual machines, down to an average of 10 minutes. Everyone on the team noticed the difference immediately.
[Q9] Which Bitrise features are bringing you the most value?
[Ganesh] For me, the Bitrise Insights feature has been really helpful at showing us where we can improve and highlighting when code changes have had an impact on build speed. For example, when we were modularizing our app and splitting a big monolith into smaller chunks, we wanted to make sure it didn’t slow things down. If a module had dependencies on 10 or 20 others, that could easily affect build time. With Insights, it was easy to see exactly when a change increased build time, which was super useful. Overall, it just makes it easier to troubleshoot issues with the build system and fix them before they have an impact.
I also really appreciate how fast the Bitrise team is at updating things like Xcode and Gradle. In our old setup we had to do all of that ourselves, and we know what a pain it is to keep everything working. Now we don’t have to think about it, which is brilliant.
[Q10] What other benefits have you noticed since moving to Bitrise?
[Ganesh] Obviously, build time is a big change for us. But what’s less visible is the amount of time developers used to spend maintaining the DevOps setup versus working on user stories and delivering value. It’s hard to put a number on, because you don’t always see how much time gets lost troubleshooting builds.
Of course, waiting an hour and a half for a build was painful, but worse was losing weeks just to update Xcode or keep machines running. During the pandemic, our Mac Minis were in the office, so if one went down, product development basically stopped until someone could go in and fix it. That was a real pain.
In our previous setup, maintenance was always up and down. Sometimes we’d spend a whole sprint just fixing build issues, then things would run smoothly for a few months, and then it would happen again. It could even be something as simple as someone switching off a Mac Mini. With physical machines there was always that looming threat that something would break. And when something happened, we had to drop everything, no matter what else was going on. There was always unplanned work derailing our focus. But now with Bitrise, thankfully that’s all in the past.
[Q11] How has Bitrise impacted your developer experience?
[Ganesh] It allows the team to fully focus on mobile development and where we can bring more value to customers without the distraction of unplanned issues and maintenance headaches. Given the intense pressure we face in the automotive industry, this has been invaluable.
[Q12] What’s next on the horizon for Elli and your partnership with Bitrise?
[Ganesh] We are looking to continue improving our automated testing to keep raising the quality of our apps. We’re also exploring moving to GitHub from Azure DevOps for code hosting as it will offer us tighter integration with Bitrise out of the box and open up even more possibilities for the future.
We also want to continue to take advantage of the latest machines to keep improving our build speed and exploring other features like Bitrise Release Management and Build Cache to drive new efficiencies. Now with Bitrise we are now able to devote more time to these things, which was previously impossible.
It's been a really collaborative partnership so far, and we're looking forward to seeing where it takes us next.
