Atom bank: Empowering a digital-only bank to transform the way people handle their finances

About Atom bank

Atom bank, the UK’s first app-based bank is here to do the right thing by its customers. To stand up against the big banks, to save customers time, offer the best products and to offer them genuine value, empowering them to take control of their finances.

Industries: Financial Services & Insurance
Location: United Kingdom

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About Thought Machine

Google Cloud Premier Partner Thought Machine offers banks a fully customizable modern API-based platform.

With Google Cloud, Atom bank has built a brand new cloud-based banking stack designed for security, scalability, and a seamless customer experience.

Google Cloud results

  • Increases speed and lowers latency on the app by leveraging Google Cloud-based infrastructure
  • Improves customer experience with enhanced infrastructure control and the ability to quickly respond to any technical issues
  • Develops a culture of enhanced agility, with the ability to cut environments lead time by up to 98%

Spins up new environments faster, from 42 weeks to just one week

Since Atom bank launched in 2016, it has become very popular, very quickly. The UK’s first app-based bank, it combined the convenience of a mobile experience with consumer-friendly lending and saving policies. One reason for Atom bank's success, says CTO Rana Bhattacharya, is the bank’s focus on providing a simpler experience for its customers, while offering extremely competitive rates. “We use technology to cut down on the overheads of more traditional banks and provide a slick, smooth service that you’d get from the best mobile apps,” he says. “A broker can fill out a mortgage application and get an offer in principle for the customer in around 14 seconds.” The mortgage service is based on a web-based broker channel, and after the mortgage application is submitted, the app guides the customer through the process.

“We were growing at a very fast pace, but our IT infrastructure was managed by a third party in a data center. With Google Cloud, we could handle our own infrastructure and engineering capability and ultimately take control of our own destiny.”

Rana Bhattacharya, CTO, Atom bank

As Atom bank attracted more customers and wanted to offer more products, it began to feel that its existing infrastructure was slowing growth and limiting the bank’s agility. In 2017, it began searching for a cloud-based alternative. After evaluating its options, the bank felt that Google Cloud did more than any other cloud provider to give it a sense of autonomy and independence.

“We were growing at a very fast pace, but our IT infrastructure was managed by a third party in a data center,” says Rana. “With Google Cloud, we could handle our own infrastructure and engineering capability and ultimately take control of our own destiny.”

Sustainable growth with the cloud

At the time of Atom bank’s launch, existing financial regulations weren’t amenable to cloud computing, so the bank partnered with a core banking-focused third party to host its infrastructure in an on-premises data center. “That worked really well to begin with, but we always had our eye on the cloud because we knew it could help us be much more nimble,” says Rana. When the regulatory climate evolved to accommodate cloud computing in 2016, Atom bank began the search for an alternative infrastructure.

An essential part of Atom bank’s early success was the ability to grow rapidly and sustainably. So it wanted to ensure speed and reliability even as it gained more customers and added more services. As a “challenger bank” competing against much more established competitors with vast resources, Atom bank had to carefully decide how to spend its time, effort, and money on improving the offering. Some third-party applications would always need on-premises servers to work. But with a cloud-based infrastructure for the core banking elements, Atom bank could start new projects or launch new environments without having to sink costs into new hardware every time. “We were looking for agility at a more economic cost point, and we could achieve that with the cloud,” explains Rana.

Atom bank examined a range of cloud providers before deciding on Google Cloud for its technical capabilities, level of service, and competitive pricing. “We felt with Google Cloud that we were working closely with a partner rather than simply dealing with a supplier,” says Rana. “When we engaged with its engineers, we could see that they were invested in helping us succeed.”

“Google Kubernetes Engine gives us a lot more granular control than a traditional banking architecture would. If an incident happens, we get notified and we can deal with it very, very quickly before it becomes a problem.”

Simon Dawson, Head of DevOps, Atom bank

Building a cloud-native banking stack

In the second half of 2019, Atom bank began its modernization journey to build a new banking stack on Google Cloud. To ensure a smooth transition, Atom bank planned the project in two phases. The first would involve getting the network middleware onto the cloud, and the second would redesign the core banking stack for a microservices-based architecture utilizing a variety of in-house and external systems fit for the cloud.

In the first phase, Rana’s team began first by moving its digital mortgages website to Google Cloud, as a low-stakes way of learning how to work with the new technology. While on paper it was a simple website migration, Rana explains that it was an important step in building a secure network and foundation for the broader bank. “As a website, it wasn’t very complicated or resource-heavy, and it enabled us to familiarize ourselves with the Google Cloud platform. Getting the website live gave us more confidence and motivation for the next step in our transition.”

What came next was the rebuilding and redesigning of much of Atom bank’s stack in the cloud. By this point, Atom bank had hired a team of DevOps engineers. By the end of 2019, the bank had re-created the middleware for the core banking elements on Google Cloud in parallel to the existing infrastructure, minimizing disruption, and launched a brand new app for both the Android and Apple app stores.

At this stage, Atom bank brought its middleware elements onto Compute Engine virtual machines with static data held in Cloud Storage. For enhanced security, Google Cloud products can be encrypted with customer-managed encryption key (CMEK) technology in the Cloud Key Management. “As a financial institution, security is absolutely paramount for us,” says Simon Dawson, the Head of DevOps at Atom bank. “The ability to generate and manage our own keys means that only we are in charge of access to our most sensitive data, and we’re not dependent on third parties.”

After Google Cloud expanded CMEK capabilities to Google Kubernetes Engine (GKE), the bank quickly began to shift from an architecture built around virtual machines to one designed around microservices run with Kubernetes, the open source container technology founded at Google. With Kubernetes, the DevOps team can quickly provision clusters and scale them up or down as required. At the same time, GKE gives them an unprecedented level of insight into the infrastructure.

“Google Kubernetes Engine gives us a lot more granular control than a traditional banking architecture would,” says Simon. “If an incident happens, we get notified and we can deal with it very, very quickly before it becomes a problem.”

In early 2020, as Atom bank was well on its way with the second phase of the modernization, the UK went into lockdown to curb the spread of COVID-19. With its cloud infrastructure already in place, the bank was able to pivot to adapt to the new situation with relative ease. “We’d already built the foundation for working entirely in the cloud, so within three weeks we were all set up to continue working from home for the whole business,” says Rana.

By June, Atom bank had completed the second phase of the modernization, which involved building the rest of its banking infrastructure and systems on Google Cloud. For its core banking services, it used Vault, a cloud-native platform designed specifically for banks by Thought Machine, a Google Cloud Premier Partner. With GKE, the bank also designed areas such as a new monitoring and notifications system for its infrastructure and redesigned its data architecture.

Real-time data streaming and data management

With its redesigned banking stack on Google Cloud, Atom bank is now streaming its data in real time, for the first time. To do this, it uses GKE to run the open-source streaming platform Apache Kafka. Atom bank’s new data streaming capabilities allow it to run analyses on products or customer cohorts in real time for instant responses, instead of waiting on the batch processes it used on the previous infrastructure. “Having real-time data means we can move our reporting suite from a nightly batch job, based on yesterday’s data, to a real-time dashboard,” explains Simon. “This delivers the most up-to-date information to the right people in the business, at a click of a button, enabling them to make decisions based on current data.”

On the back end, Atom bank relies on Cloud SQL as the relational database for its banking platform and data architecture platform, with a set of microservices running on GKE. After ensuring that Cloud SQL met its security requirements around CMEK compatibility and multi-region capabilities, Atom bank quickly migrated most of its virtual machine workloads from its previous relational database.

The bank now uses Cloud SQL extensively, with automation pipelines that enable it to rapidly build highly available and resilient instances and databases. The DevOps team spins GKE clusters up and down within minutes to deploy microservices, starting with the Google Cloud SQL element of the architecture, whose instances it doesn’t rebuild as frequently. When it does want to rebuild a Cloud SQL instance, the team uses automated Terraform or Ansible pipelines to spin up the new instance and database in minutes.

“With Cloud SQL, we gain plenty of operational advantages,” says Simon, “because Google Cloud takes care of routine tasks such as security patching, upgrades, and backups. We don’t have to worry about availability or reliability with any of our workloads on Google Cloud SQL, and that means we can focus on building.”

The impact of migrating to Cloud SQL extends to Atom bank’s customers as well. As the backbone of its data management platform, Google Cloud SQL helps to provide the bank with real-time data on how customers use its products. Actionable insights delivered by this platform enable Atom bank to better tailor future offerings to its customers. Meanwhile, Cloud SQL also enables a variety of core functionalities on the Atom bank mobile app, ranging from providing the metadata for all customer documents and notifications, to enabling the list of products available to customers using the app.

Atom bank also uses BigQuery ML to analyze its Google Cloud billing account data for a clear overview of its spend per service, and per environment. This has helped to keep costs optimized during COVID-19 and beyond.

Higher speeds, smoother performance

With Google Cloud, Atom bank has rebuilt an entire banking stack on the cloud with minimal disruption to its service. Customers have noticed an improvement, as Rana shares: “Our app store ratings have shot up and we’re regularly seeing words like ‘easy,’ ‘safe,’ and ‘fast’ come through. Moving to Google Cloud has supported improving our speed and lowered our latency and friction in the user experience, and that’s reflected in the feedback we receive from customers.”

The improved service is not just down to better networking and lower latency, but also the architecture and notifications system that Atom bank has built. When incidents do occur, the bank can find and deal with them much more quickly than before. For example, in late 2020, when one of the products saw a surge in customer usage, the DevOps team saw a notification about a potential lack of compute power and were able to increase the number of CPUs within hours. “The customers didn’t see any drop in service because it never became an issue for them,” says Simon. “That’s what’s great about the ability to respond on the same day. We still get the odd incident, but we can be proactive about fixing them before they become problems.”

“Google Cloud has allowed us not only to bring in changes like real-time data streaming, but also dramatically improve development times, with same-day production changes. That means we are much more agile as an enterprise, and we can focus on the things that really matter for our customers.”

Rana Bhattacharya, CTO, Atom bank

Cloud-native products for an easier banking experience

Atom bank has also improved the speed at which it can develop new products. On the old infrastructure, it used to take 42 weeks to set up a new development environment. On Google Cloud, the team can do it within a week, which means that Atom bank can run parallel projects and work streams and ultimately get to market much more quickly.

According to Rana, the shift has helped Atom bank to transition from a state of no DevOps capability and dependence on third parties, to one of proactive, problem-solving developers who are constantly looking for ways to improve features and push boundaries. “Google Cloud has allowed us not only to bring in changes like real-time data streaming, but also dramatically improve development times, with same-day production changes,” says Rana. “That means we are much more agile as an enterprise, and we can focus on the things that really matter for our customers.”

One of those projects was a brand new Instant Saver account which the bank launched to the public in September 2020, three months after completing the modernization journey. Being able to fully test the product in multiple environments meant it was more mature at launch, and customer reviews reflected that. “The first product we developed for the new cloud platform was our Instant Saver account, so when it went live, we were a little bit nervous,” says Simon. “But there were absolutely no issues with its performance. It’s been almost boringly smooth, and that’s a good thing!”

Following the successful release of its Instant Saver account, Atom bank plans to fully migrate away from its old banking stack hosted in data centers onto its new modern cloud banking stack and is currently hard at work developing new products and services for release in 2021. “Our vision is about making banking easier for customers, so that’s what we’re focusing on right now,” says Rana. “We want our customers to feel like they can do everything they need to within the app, rather than having them go to a high street bank branch. We want them to see banking as something you do, rather than somewhere you go to.”

Tell us your challenge. We're here to help.

Contact us

About Atom bank

Atom bank, the UK’s first app-based bank is here to do the right thing by its customers. To stand up against the big banks, to save customers time, offer the best products and to offer them genuine value, empowering them to take control of their finances.

Industries: Financial Services & Insurance
Location: United Kingdom

About Thought Machine

Google Cloud Premier Partner Thought Machine offers banks a fully customizable modern API-based platform.