#91: Asynchronous communication: loose coupling in distributed systems

Yukihiro Matsumoto, the creator of Ruby programming language, famously said: “I hope to see Ruby help every programmer in the world to be productive, and to enjoy programming, and to be happy.” Honestly, not many programming languages were built with developer’s happines in mind. And to be honest, Ruby is a joy to work with. It’s fairly easy to learn, easy to read, yet, very powerful. Also, with the appearance of Ruby on Rails, it became insanely productive. But first things first. Read more: https://nurkiewicz.com/97 Get the new episode straight to your mailbox: https://nurkiewicz.com/newsletter

Border Gateway Protocol, BGP for short, is probably the most important protocols you might have never heard of. Well, you did at least once, in October 2021. When Facebook, WhatsApp, Instagram and Messenger all went down because of BGP misconfiguration. Or that one day back in 2008 when all YouTube traffic was accidentally routed to Pakistan. Because of BGP… misconfiguration. So what’s the big deal with BGP? First we must understand how the Internet works. Read more: https://nurkiewicz.com/96 Get the new episode straight to your mailbox: https://nurkiewicz.com/newsletter

SQLite is by far the most common SQL database ever deployed. Are you lsitening to this on iPhone or Android device? It runs SQLite. Or maybe through a web browser? Chrome, Safari, Firefox, Opera and Android Browser all use SQLite underneath. Are you running MacOS or Windows? It’s built-in. Most Linux distributions have it as well. “But I’m listening to your podcast while driving a car”, you say. Well, most automotive systems use SQLite internally. If you happen to listen to my podcast while coding in PHP or Python, they include SQLite out-of-the box. Oh, and it’s the default choice for Ruby on Rails as well. I’m pretty sure SQLite is used somewhere on the International Space Station and it maybe even landed on other planets? So, what makes this unsung hero so popular to run at least one trillion databases worldwide? Read more: https://nurkiewicz.com/95 Get the new episode straight to your mailbox: https://nurkiewicz.com/newsletter

Scala is a programming language running on the Java Virtual Machine. It’s statically typed, and you can use it both as functional and object-oriented language. Even at the same time. The functional side of Scala supports higher-order (and higher-kinded) types. For those of you know what it means. On the other hand, object-relational features of Scala are equally strong. Including powerful trait composition, that you can somewhat compare to multiple inheritance. Combine than with great Java interoperability and no wonder why Scala became a go to language for many ex-Java developers. Read more: https://nurkiewicz.com/94 Get the new episode straight to your mailbox: https://nurkiewicz.com/newsletter

K-means clustering is an algorithm for partitioning data into multiple, non-overlapping buckets. For example, if you have a bunch of points in two-dimensional space, this algorithm can easily find concentrated clusters of points. To be honest, that’s quite a simple task for humans. Just plot all the points on a piece of paper and find areas with higher density. For example, most of the points are located on the top-left of the plane, some at the bottom and a few at the centre-right. However, this is not that straightforward once you can no longer rely on graphical representation. For instance, when your data points live 3-, 4- or 100-dimensional space. Turns out, this is not that uncommon. Let me clarify. Read more: https://nurkiewicz.com/93 Get the new episode straight to your mailbox: https://nurkiewicz.com/newsletter

Clojure is a dynamically, strongly typed programming language. It’s a dialect of Lisp running on the Java Virtual Machine. Lisp is 6 decades old and has a really weird syntax. That weird syntax is called Polish prefix notation. Basically, in every other language you’ve used math operators like plus or minus are infix. It means they are placed between operands. For example, 1 + 2. In Clojure, you always put the operator (or any other function for that matter) in front. So simple addition becomes… + 1 2. Read more: https://nurkiewicz.com/92 Get the new episode straight to your mailbox: https://nurkiewicz.com/newsletter

There are two main ways to communicate between components in your distributed system: synchronous and asynchronous. Synchronous communication is like making a phone call. The system on the other side must be present and you actively wait for a response to your every question. Examples of this style include REST, SOAP and GraphQL. Read more: https://nurkiewicz.com/91 Get the new episode straight to your mailbox: https://nurkiewicz.com/newsletter

After many dramatic events around Twitter lately, many people, including myself, began experimenting with Mastodon. Superficially it’s an open-source clone of the former that anyone can deploy and host. However, once you look deeper, it’s actually a completely different philosophy and architecture. Let’s focus on how Mastodon federated network is built. To understand the difference, we’ll start from scratch. Read more: https://nurkiewicz.com/90 Get the new episode straight to your mailbox: https://nurkiewicz.com/newsletter

RabbitMQ is a message broker, allowing asynchronous communication in distrubuted systems. The key advantages of RabbitMQ include: 15 years of open source history, battle proven Erlang implementation and support for industry standard protocols. RabbitMQ is among the most popular implementations of message brokers. Others include ActiveMQ for Java, celery for Python and Kafka - if you consider it a message broker. Also, pretty much all cloud providers have their proprietary implementations, like, Google Pub/Sub, Amazon Kinesis, Azure Service Bus and so on. RabbitMQ at its core implements AMQP, a standard protocol for information interchange. So not only it’s open source, it’s also built on top of open standards. Read more: https://nurkiewicz.com/89 Get the new episode straight to your mailbox: https://nurkiewicz.com/newsletter

Many people, when asked about SLA, simply shout 99%. The correct answer to that question is probably a long, boring PDF, written by lawyers. Yes, SLA is a legal obligation. Not a metric or a number. You probably meant SLI or SLO. Read more: https://nurkiewicz.com/88 Get the new episode straight to your mailbox: https://nurkiewicz.com/newsletter