In this episode, Ashley Peacock, a staff engineer and architect who is passionate about visualizing software ideas, is interviewed by host Akshay Manchale. They examine the reasons behind the underutilization of diagrams in software engineering, the rise and fall in popularity of modeling tools and notations (such as the traditional Unified Modeling Language, or UML), and, most importantly, the continued significance of sequence diagrams. Sequence diagrams have two primary uses, according to Peacock: (1) depicting user flows through a system (actor → service → backend → database) and (2) illustrating message flows between classes/components in code. He highlights the fundamental function of diagram communication instead of discussing the drawbacks of overly rigorous UML adoption.
The reason I chose this Source
I chose this episode because our course on Software Construction, Design & Architecture emphasizes modeling techniques, and I wanted to learn more about how sequence diagrams are used in modern software engineering practice than just the concepts found in textbooks. Hearing a practitioner discuss diagramming in real-world scenarios felt incredibly relevant to me as someone with a background in finance and statistics who wants to improve my technical design abilities (particularly because modeling can be used in business/technology initiatives).
Reflections And Actions
It became clear to me again while listening to Peacock that what matters most is how well you communicate, not how well you write. I discovered that sequence diagrams are more than just “another UML artifact.” They connect use-case thought (what the user does) and structural modeling (what the system has). Making a sequence diagram of the steps “User submits order; OrderService validates; InventoryService checks stock; PaymentGateway processes payment; confirmation sent to user” can help everyone (business, product, architecture, and development) understand the flow. At the beginning of my work, I also put too much emphasis on static diagrams like class and ER diagrams and not enough on the temporal aspects of “who calls whom when” and “what’s the sequence.” I learned from the show that sequence diagrams can be used as a contract: you can map out how things work together before you write any code, which helps you avoid misunderstandings.
To improve my future work, I will choose a key scenario (like “customer checkout,” “report generation,” or “billing and collections”) and make a sequence diagram to help me understand it better when I do system analysis for a project, whether I’m a financial or technical analyst or designing a business process. The chat changed how I think about tools. I’m going to start using lightweight diagramming tools (Mermaid, PlantUML, etc.) that let diagrams live with code instead of being buried in PowerPoints. I can see that sequence diagrams aren’t just ideas; they can also be used to communicate design ideas, make sure that architectures are aligned, and keep records.
Citation
I’m Ashley Peacock. (5/31/2023). Ashley Peacock talks about diagramming in software engineering on SE Radio 566. se-radio.net
From the blog Site Title by Roland Nimako and used with permission of the author. All other rights reserved by the author.


