Global Day of DDD - Chris Simon - Modular Monoliths and Microservices

In November, we'll be participating in the Global Day of DDD organised by the Virtual DDD meetup.

This means you have two options for joining the DDD AU meetup this week:

• Option 1 - join as a regular DDD AU meetup - RSVP here to either join in Sydney in person or join us on Zoom (link will be sent out on the day)
• Option 2 - join the global Day of DDD event on Gathertown. We'll be live streaming into Gathertown so you can still join the DDD AU meetup, but you'll also be able to see other local meetup events, and participate in an open space/discussion with global DDD enthusiasts. There is a $5 ticket price to cover platform costs.

Whichever you choose, we look forward to seeing you there where Chris will be talking about "Modular Monoliths and Microservices with Kruchten's 4+1 Views" - a way to think holistically about systems design that incorporates both DDD concepts and microservices/devops ideas.

Agenda:

5:00pm - Space opens, streaming from Global Day of DDD on projector

5:30pm - Food arrives, networking

6:00pm - Welcome

6:15pm - Chris Simon - "Modular Monoliths & Microservices with Kruchten's 4+1 Views"

7:15pm - Wrap-up & farewell

The live-stream link will be sent out to attendees on the day - when RSVPing, please indicate if you will be there in person or on the live-stream to help with catering.

Modular Monoliths & Microservices with Kruchten's 4+1 Views

Kruchten's 4+1 views is a way of understanding systems that uses 5 different 'views' of the system, allowing to design and scale different aspects of the system in response to different triggers:

1. The logical view represents functional requirements & scales with functional complexity
2. The process view represents executable processes & how they interact & scales with concurrency and deployment requirements
3. The physical view represents the hardware & networks that the processes execute on & scales with load and throughput
4. The development view represents the system as seen by developers (e.g. code) & scales with the number of teams and team size
5. The scenarios view represents the various scenarios in which the system is used & highlights how components in the other views interact

A modular monolith is a system that has 'scaled up' the logical view (multiple modules), but not scaled up the process or physical views (single process, single hardware configuration).

We've used the 4+1 to design a system as a modular monolith - saving time, cost and complexity when the team was small & load was low and allowing simpler realignment of module boundaries as we were still discovering the domain. We gradually extracted modules into microservices as needed once we had built confidence in boundaries, when load grew and as the teams expanded and needed autonomy.

In this talk we'll explore what went well, mistakes we made & tips for adopting this approach.

About Chris Simon

Chris is a technology coach and advisor helping technology teams drive business success. He has a particular focus on helping startups realise their vision and new CTOs flourish in their roles. He also supports executives & boards with strategic technology advice, and engineering teams with training, mentoring and consulting in architecture, quality, domain-driven design and test driven development.

He is a regular meetup & conference speaker (https://chrissimon.au/speaking/) and to support teams using Domain-Driven Design, he recently launched https://contextive.tech & co-founded the DDD Australia meetup.