Micro-frontends decisions framework

In the past year (2019) I spent a lot of time talking, writing, podcasting and just chatting with people about micro-frontends.
I’m truly passionate about the topic, mainly because it’s still an unexplored land where challenges arise every single day.

During all my talks, workshops and webinars I was building step by step a mental model that allowed me to simplify my thoughts for making them approachable by people listening to me or reading my contents.
I’m sure there is still a lot of work to do but from the feedback I received so far, I was able to explain in a reasonable way what I had in my mind.

Recently I had the pleasure to do a 2h workshop in Bergen (Norway) about this topic and during my presentation (literally on the stage) I realized that I was very close to simplify even further the decisions process for embracing a micro-frontends architecture.
In JavaScriptland we are used to choosing a framework and getting along with that for the entire lifecycle of a project, sometimes we change it in favor of another one but many times we stick with it for many months/years till the end of life for a specific project.
Every time we use a JavaScript framework, someone else made architectural decisions that we live with (or trying to) and we focus on what matters the most from a business point of view: the features of an application.
This doesn’t mean we have an easy challenge in front of us at all, we still have an essential part of this “game” taking the right design decisions for delivering the project, but first, we need to focus on having a solid base that allows us to build on top of it, aka the architecture.

Martin Fowler defines software architecture as:

“Software architecture is those decisions which are both important and hard to change”

Based on this definition, focusing on the key things, even better, the most important decisions for defining a micro-frontends architecture I came up with 4 pillars we have to decide upfront when we start architecting a micro-frontends project.
Those pillars can be summarized in: