It is said that as of 2020, 70% of the Fortune 500 companies and 92 of the world’s top 100 banks still use Mainframes (IBM zSeries) for their critical system infrastructure. The usage of IBM iSeries (AS 400) is quite significant as well. According to Reuters, there are 220 Billion lines of COBOL running today; 95% of all ATM transactions still go through COBOL code, with most of this code running on one of the above mentioned platforms.

The consistently high usage of mainframes and other related systems can be distilled down to several key factors, the main ones being…


One morning, while randomly wasting my time on social media, I saw the above picture pop up on my Facebook timeline reminding me that it has been 11 years to the date (2010/05/25) that this was posted. After the initial rush of nostalgia was gone, it dawned on me what this picture represents and how it has evolved throughout the past decade, while still being fundamentally the same, a “Distributed System”.

While not being very “distributed” in a purely physical sense, the above picture shows the system that myself and three of my buddy’s created for our final year research…


Having been adversely affected by the infamous AWS us-east-1 outage of 25th November 2020 (I intentionally refrain from using the phrase “being a victim of”), after the initial confusion settled down, and i was able to get a full nights sleep, my thought process eventually shifted towards ways of improving the resilience of our production systems.

AWS has since clarified (in surprising detail) what caused the Kinesis stream outage and how it affected the other services like Cognito. Based on that information, Cognito was only using kinesis streams for analytics gathering and should not have been critically affected. But a…


For the past few years, hearing the terms “distributed” and “data store” in a single sentence would immediately move my mind to visualize a single word, “Redis”. Now, this was not entirely down to my ignorance. A quick googling would remind you that Redis is still the #1 in the rankings for Key-value stores and ranked #8 out of all DB engines. However, as the proverb goes, there is more than one way to skin a cat. And some of these ways are obviously more equal than others. Behold Apache Ignite.

Apache ignite is an in-memory computing platform that is…

Dishan Metihakwala

Software Architect — SyscoLabs Sri Lanka

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