A 50x speed improvement — While running DynamoDB workloads in production with over 500 GB of data for a couple of years, I accumulated a couple of lessons learned that I’ll be sharing. One of them I wrote previously about: How to Speed-up Long DynamoDB Queries by 2x. AWS DynamoDB is a great database. It’s…

History Exactly 5 years ago, I wrote about running LibreOffice in AWS Lambda for the first time. It enabled people to generate PDFs from any office file format for a fraction of a dollar. As opposed to a traditional server-based approach, it utilizes serverless computing to drastically reduce costs and get…

Learn how to deploy beta.api.example.com from a different AWS account that doesn’t own the example.com domain. At my current company, we started development from a single AWS account. As the product grew in size, we faced a need to provision multiple AWS accounts to share the infrastructure across them. A…

Note: “Long” queries are the ones that scan over 2 MB of data. The trick described in this article only applies to those. TL;DR; Implement parallel pagination from both ends instead of a sequential one. Situation Imagine you’re in a situation when you have thousands of items under the same partition…

Reducing artifact size proportionally correlates with the cold start latency. The most obvious way would be to use webpack and do tree shaking. But I’m not a fan of that approach. …

Some services require you to put a file (usually a .txt one) into the root of your domain to prove you own it. When your API runs on a server, it’s a pretty straightforward task, but not so much when your API is Serverless and runs on AWS API Gateway. …

Or how to overcome the 5 minute Lambda execution limit — So last December I was rewriting our indexing microservice in a serverless way. Along the way, I had to migrate Elasticsearch from version 2.3 to 6.1. Not that I was eager to rush the upgrade, quite opposite. But one day Elastic Cloud announced version 2.3 is approaching the end-of-life. As…

Did you know you can convert almost 100 document formats to PDF with LibreOffice? Did you know you can do this in Lambda now? TL;DR; online demo and github sources — This short post will answer 2 simple questions Why? and How? Skip to How. Why? To not ruin your expectations, let’s clarify some things from the start. This is not something you can run in production, at least yet. Ok, so let’s go on. If you ever had to work with…

A few weeks ago something strange began to happen. Random Lambda functions from ALL environments throwing errors. My face turned white. MongoError: no connection available at nextFunction (/var/task/node_modules/mongodb-core/lib/cursor.js:540:25) at Cursor.next No clear pattern. Same code for mongo connection worked fine for 11 months and broke at 1 day. 0.0004% of…