Managing complexity, testing, culture key to robust bank digital systems: experts

AS BANKS increasingly move their offerings into the digital realm, building robust platforms will require load optimisation, rigorous testing and a development culture focused on design and quality, technology experts told The Business Times.

Those insights came in the wake of DBS Bank’s recent spate of digital services outages. The outages – three significant disruptions in 18 months – drew a rare public rebuke by the Monetary Authority of Singapore, which imposed an additional capital requirement on DBS.

Managing complexity

Cassandra Goh, deputy chief executive of banking solutions provider Silverlake Axis, said it is common for organisations to shift too much of their operations to the cloud.

For instance, credit card payments processing can slow in the cloud when online retailers run large promotions and transaction volumes surge. A more optimal setup might instead handle typical loads on local servers while transactions going to these online retailers are handled with cloud services.

“I think for a while we went all or nothing, we went one way too far,” she said.

Dennis Khoo, managing partner of digital consultancy All Digital Future, noted that banks have to grapple with a lot of distributed databases for different accounts, such as credit cards and loans. This will necessitate reducing the load on certain databases, said Khoo, who was formerly group head of UOB’s TMRW digital group.

For example, if customers are trying to view their credit card transaction details, then a bank’s app could give customers the option to only select individual credit cards instead of providing a full transaction history of all the user’s cards.

“That would make the response time in retrieving the information faster. It also ultimately makes for less calls to the backend,” he said.

He added that such optimisations can help when there are peak loads, such as when it is payday and everyone is logging in to check their bank balances.

Large libraries of prewritten code that are optimised for different tasks can also enable modular development. These libraries prevent different developers from writing code that only they know how to maintain, which hinders maintenance when they leave. Furthermore, modular, efficient and well-documented code streamlines the addition of new functions.

“A startup can say that, ‘yes, my software is very good’. But within three years, your complexity increases to the extent that you look more like an incumbent,” Khoo said.

Shashank Tripathi, an instructor at the National University of Singapore, added that modularity can improve resilience. For instance, a single slow element will not break the entire app in the same way that a website might complete loading the text of an article while the larger image files are still being rendered.

Testing well

But even the best-planned digital systems must be challenged, because things fail.

Tripathi noted that in complex systems, certain functions may have been built on top of unoptimised legacy code, which could be bulky and inefficient. Companies need to be thorough in testing, he said.

Modules must be tested individually and together as a combined system, he explained. In a number of cases, he noted that apps crash because teams were not thorough in their testing.

For instance, companies need to pay attention to the non-functional requirements of software, such as the load times or recovery mechanisms of certain functions.

When these areas are overlooked, they are not tested for, which leads to slowdowns and crashes when functions are used in unexpected ways.

Even when bugs are fixed, companies have to undergo regression testing – the process of running a fresh set of tests to make sure that the fix did not break something else.

“Testing is always being paid less importance…it is something that doesn’t look very lucrative. People are so busy in just the development and launching the project as soon as possible,” Tripathi said.

Cultural factors

The foundation for those practices are laid in the development culture, the industry players said.

Silverlake Axis’ Goh noted that retail banking can be competitive, which may lead business teams to prioritise introducing new features over optimising old ones.

“On the backend, your IT side is trying to catch up with the business side as they ask for more features to come in.

“Meanwhile you have a budget that says ‘please don’t grow your IT costs by too much’ so there is quite a bit of tension,” she said.

All Digital Future’s Khoo said that he hopes banks can take the time to consider product designs carefully.

He noted that as banks in Singapore and many parts of South-east Asia have already achieved quite high levels of service, it is unlikely that they will release any breakthrough features that cannot be copied.

Rather than searching for the next big feature to release, Khoo believes that their efforts are better spent searching for 10 irritating issues to fix in their digital platforms and swaying customers with a superior user experience.

NUS’s Tripathi said that he has seen teams of developers face difficulties in communicating their issues.

“If you are not transparent to your team, if you are not adapting to your changes, you are just repeating your mistakes again and again,” he said.