TLC #14: Communicate your Tech Design better with C4 Model
The topic for this month is to "design better tech solutions" and the first post in this series is on C4 model. (Issue #14, 02 Jun 2024)
Hey, Ashwin here! Welcome to edition #14 of the Tech Lead Compass newsletter!
As engineers and tech leads, we often underestimate the need for our tech designs to be cognizable.
Simpler the design, the higher its utility and purpose.
C4 model is one of the popular and proven ways to visually communicate your design to a wide range of audiences. Its beauty is the “drill down” method, making it usable by technical and non-technical audiences.
What is a C4 Model?
C4 models are a hierarchical abstraction of software systems, achieved through a set of diagrams. They are designed to be notation and tool-independent, which can be applied to almost all type of systems.
It is an “abstraction-first” model, that reflect how software architects and developers think about building software.
C4 stands for:
System Context
Container
Component
Code
In ascending order of granularity, each of these diagrams gives a more detailed view of the software system that’s being built.
What are the C4 Model Abstractions?
4 levels of abstraction are at the core of a C4 Model.
Software system - the highest level of abstraction of any system that has some utility (e.g., a maps application)
Containers - a software system is made up of one or more containers (e.g., applications, data stores, etc.)
Component - each container is made up of several components (e.g., relational data store, NoSQL data store, etc.)
Code - finally, each component is implemented by software code using a tech stack (e.g., MySQL, DynamoDB, etc.)
Each of these abstractions is represented as C4 diagrams.
C4 Model Diagrams
System Context Diagram
The system is visualized as a single box which is at the center
This diagram shows how the system interacts with its environment and users
Focus is on the people and interacting systems, not on technology or tools
Everyone, irrespective of their technical acumen, must be able to understand this diagram
Container Diagram
A container view represents various applications that constitute the system
This diagram can show the major technology choices and how the containers interact with each other
It is intended for a technical audience, but anyone with a need to know how the system works can use this diagram
Component diagram
In this diagram, the container is decomposed into structural building blocks and their interactions
Each component’s responsibilities, interaction with other components, and technical details are called out here
Software architects and developers are the primary intended audiences
It is not recommended for all teams, so use it only if you think it adds value
Code diagram
Represents how each component is implemented as code - using UML diagrams, ER diagrams, etc.
Usually generated using IDE or UML modeling tools
This level of detail is normally required only for complex components
In summary, C4 diagrams improve the communication efficiency of your software design. The level of detail and type of diagrams is contextual to the system under design.
Now on to the must-read news from the past week…
5 “Must-Read” Tech News for the Week
Elon Musk and Meta’s Chief AI Scientist, Yann LeCun, recently engaged in a Twitter exchange that exposed key disagreements on AI risks. LeCun criticized Musk for promoting conspiracy theories while claiming to seek a “maximally rigorous pursuit of the truth.” Musk fired back, questioning LeCun’s recent scientific contributions
Google has introduced new AI-powered features for its Chromebook Plus line of devices. These productivity-focused laptops now come with a writing assistant, a wallpaper creator, and easy access to Google’s Gemini chatbot.
Microsoft has added an official Copilot bot within the messaging app Telegram, which lets users search, ask questions, and converse with the AI chatbot. It will only support text requests for now and no image generation.
Google launches Fitbit smartwatches for kids (9to5Google)
The Fitbit Ace LTE is Google’s newest wearable powered by Wear OS and meant to encourage kids (ages 7+) to be healthy through games, while also serving as a parent-child communication and real-time location device
A hacker group called ShinyHunters claims to have stolen sensitive data from over 500 million Ticketmaster customers. The group is selling this 1.3 terabyte-sized trove of data for a one-time price of $500,000 on a popular hacking forum.
That’s it for the week!
I’ll be taking my first annual vacation next week. So the next TLC issue will be on 16 June 2024. Happy holidays to everyone in Singapore!
In case you missed the past articles, feel free to read them from here:
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