MongoDB & DKatalis’s Bank Jago, Empowering over 500 Engineers

DKatalis, a technology company specialized in developing scalable digital solutions, is the engineering arm behind Bank Jago, Indonesia’s first digital bank.

An app-only institution, Bank Jago enables end-to-end banking with features such as auto budgeting. This allows Bank Jago’s customers to easily and effectively organize their finances by creating "Pockets"—for expenses like food, savings, or entertainment.

Launched in 2019, Bank Jago has seen tremendous growth in only a few years, with its customer base reaching 14.1 million as of October 2024.

While speaking at MongoDB.local Jakarta, Chris Samuel, Staff Engineer at DKatalis, shared how MongoDB became the data backbone of Bank Jago, and how MongoDB Atlas supported Bank Jago’s growth.

Bank Jago’s journey with MongoDB started in 2019, when DKatalis built the first version of Bank Jago using the on-premise version of MongoDB: MongoDB Community Edition.

“We did everything ourselves, up to the point when we realized that the bigger our user [base] grew, the more painful it was for us to monitor everything,” said Samuel.

In 2021, DKatalis decided to migrate Bank Jago [from MongoDB Community Edition] to MongoDB Atlas. This first involved migrating all data to Atlas. Then the database platform had to be set up to facilitate scalability and enable improved maintenance operations in the long-term.

“In terms of process, it is actually seamless,” said Samuel during his MongoDB.local talk.

Specifically, MongoDB Atlas offers six key capabilities that have facilitated the bank’s daily operations, supported its fast growth, and improved efficiencies:

• Flexibility: MongoDB's document model supports diverse data types and adapts to Jago's dynamic requirements.

• Scalability: MongoDB Atlas effortlessly supports the rapid growth in user base and data volume.

• High performance: The platform enables fast query execution and efficient data retrieval for a seamless customer experience.

• Real-time capabilities: MongoDB Atlas prevents delays during transactions, account creation, and balance checking.

• Regulation compliance: With MongoDB Atlas, local hosting is possible. This enables DKatalis to meet Indonesian financial regulatory standards.

• Community support: MongoDB’s strong developer community and rich ecosystem in Jakarta fosters collaboration and learning.

All of these have also helped improve efficiencies for DKatalis’s team of over 500 engineers, who are now able to reduce data architecture complexity, and focus on innovation.

Fostering a great engineering culture and community with MongoDB

In another talk at MongoDB.local Singapore, DKatalis’s Chief Engineering Officer, Alex Titlyanov, explained that using MongoDB has been and continues to be a great learning, upskilling, and operational experience for his team.

“DKatalis has a pretty unique organizational culture when it comes to its engineering teams: there are no designated engineering managers or project managers; instead, teams are self-managed,” said Titlyanov. “This encourages a community-driven environment, where engineers are continuously upgrading their skills, particularly with tools like MongoDB.”

The company has established internal communities, such as the MongoDB community led by Principal Software Engineer Boon Hian Tek. These communities focus on knowledge sharing, skill-building, and ensuring that the company’s 500 engineers are proficient in using MongoDB.

This deep knowledge of MongoDB—and the ease of use offered by the Atlas platform—means that DKatalis’s engineers are also able to build their own bespoke tools to improve daily operations and meet specific needs. For example, the team has built a range of tools aimed at helping deal with the complexity and scale of Bank Jago’s data architecture.

“Most traditional banks offer their customers access to six months, sometimes a year’s worth of transaction history. But Bank Jago gives access to the entire transaction history,” said Boon.

The engineering team ended up having to deal with 56 different databases and 485 data collections. Some would reach 1.13 billion documents, while others receive up to 42.5 million new documents every day.

Some of the bespoke tools built on MongoDB Atlas include:

• Index sync report: DKatalis implemented a custom-built tool using MongoDB’s Atlas API to manage database indexing automatically. This was essential given the bank’s real-time requirements. Adding indexes manually during peak hours would have disrupted performance.

• Daily reporting: The team built a tool to monitor for slow queries. This provides daily reports on query performance so issues can be identified and resolved quickly.

• Add index: The Rolling Index feature from Atlas was initially used. However, the team required greater context for each index. Therefore, they built a tool that at 3:00 am automatically checks if there are any indexes to create. The tool calls in the Atlas API to create and publish the results.

• Exporting metrics: The Atlas console was used to source diagrams that were helpful. However, the team required each metric to be available per database and per collection versus cluster. The team built a thin layer on top of the Atlas console to slice up the required metrics using the Atlas API.

“The scalability and flexibility of MongoDB have been essential in helping the team handle the bank’s fast growth and complex feature set. MongoDB’s document-oriented structure enables us to develop innovative features like ‘Pockets’, and we continue to see MongoDB as an integral part of our technology stack in the future,” said Titlyanov.