Papers We Love #1 - Sagas (Hector Garcia-Molina, Kenneth Salem)

The first edition of Papers We Love meetups started with the “Sagas” whitepaper by Hector Garcia-Molina and Kenneth Salem. It’s a famous work that is foundational for managing distributed processes. You can find it here: https://www.cs.cornell.edu/andru/cs711/2002fa/reading/sagas.pdf.

Not many people know that it’s not about business processes but the proposal on tackling issues of distributed transactions in databases. We’ll check how far the current understanding is from the original idea. It’d also be a decent opportunity to discuss general issues like the Two-Phase Commit, CAP Theorem, etc.

During the meetup, we:

• Discussed fully the Saga concept both from the original database perspective and business processes management,

• Verified the impact this paper had on our tooling and practices,

• Investigated how it relates to the current way of orchestrating business processes,

• Discussed and expanded concepts there in diagrams,

• and more.

The article appeared to age well and was written in an easy-to-follow manner. Of course, the concepts were complex, but that’s why we did this meetup!

The highlight for me is that it also showed how beneficial it is to have an immutable log of operations, both from processing and resiliency. It also showed why application code should be responsible for driving business processes and why we should keep all the information on the next steps and compensation in the messages we send.

If you’re curious about how to implement it in your systems, check our previous webinars:

• Implementing Distributed Processes

• Yves Goeleven - The Fantastic 9

See also more in my articles:

• Saga and Process Manager - distributed processes in practice

• Event-driven distributed processes by example

• What texting your Ex has to do with Event-Driven Design?

• No, it can never happen!

• Oops I did it again, or how to update past data in Event Sourcing

And other people’s materials:

• Caitie McCaffrey - Applying the Saga Pattern

• Chris Condron - Process Managers Made Simple

• Martin Schimak - Know the Flow! Events, Commands & Long-Running Services

• Yves Reynhout -The Workflow Pattern

• Gregor Hohpe - Starbucks Does Not Use Two-Phase Commit

Please share the feedback if you liked it, and suggest what you’d like to see in next editions!

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Webinars:

• #1 - From CRUD to Event Sourcing

• #2 - Keep your streams short! Or how to model Event-Sourced systems efficiently

• #3 - Implementing Distributed Processes

• #4 - From CRUD to CQRS in practice

• #5 - Architecture Weekly 100 Edition - Live Q&A

• #6 - Alexey Zimarev - You don't need an Event Sourcing framework. Or do you?

• #7 - Design and test Event-Driven projections and read models

• #8 - Slim down your aggregates!

• #9 - Radek Maziarka - Modularization with Event Storming Process Level

• #10 - PostgreSQL Superpowers in Practice

• #11 - Maciej "MJ" Jędrzejewski - Evolutionary Architecture: The What. The Why. The How.

• #12 - Jeremy D. Miller: Simplify your architecture with Wolverine

• #13 - Yves Goeleven - The Fantastic 9

• #14 - Mateusz Jendza: Why Verified Credentials is the Future of Digital Identity!

• #15 - Mário Bittencourt: Leveraging BPMN for Seamless Team Collaboration in Software Development

• Papers We Love #1 - Sagas (Hector Garcia-Molina, Kenneth Salem)