C4 Context Diagram
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MermaidShow the big picture of how your system fits into its environment using the C4 model approach. This template maps users, your system, and external dependencies with clear boundaries — perfect for explaining system scope to stakeholders, planning integrations, documenting architecture decisions, or onboarding new team members to complex platforms.
How to create a C4 Context Diagram
To create a C4 context diagram, follow these steps:
01.
Define system scope
Clearly identify what system you're documenting and its primary purpose.
02.
Identify users
List all types of people who interact with your system (customers, admins, operators).
03.
List external systems
Identify all third-party or external systems your system depends on or integrates with.
04.
Set system boundary
Use enterprise or system boundaries to show what's inside vs outside your control.
05.
Create person elements
Add user personas with descriptions of their roles.
06.
Add system elements
Include your main system and all external systems with clear labels.
07.
Draw relationships
Use arrows to show how users interact with systems and how systems communicate with each other.
08.
Review & validate
Ensure all key interactions are captured and the diagram accurately represents the system context at the highest level.
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