🏛️ Government & Public Sector · C4 Architecture · Pro
Citizen Services Portal Architecture
A single online portal where citizens apply for government services: identity login, a service catalogue, document storage and payments to the treasury.
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Drawing diagram…
What this diagram shows
- One login for all services through a national identity provider
- Each department's back office gets applications through a workflow engine
- Fees are paid through the government payment gateway
Prompt used
A citizen services portal: citizens log in with national digital identity (Aadhaar-based e-KYC) via an identity provider, browse a service catalogue and apply for certificates and licences. A workflow engine routes applications to department back-office systems. Supporting documents are pulled from DigiLocker, and fees are paid through the government payment gateway. Status updates go out by SMS.
Mermaid code
C4Container
title Citizen Services Portal
Person(citizen, "Citizen", "Applies for services")
Person(officer, "Department Officer", "Reviews applications")
System_Boundary(portal, "Citizen Services Portal") {
Container(web, "Portal Web App", "Angular", "Service catalogue, applications")
Container(api, "API Gateway", "Nginx", "Routing and throttling")
Container(apps, "Application Service", "Java", "Forms and status")
Container(wf, "Workflow Engine", "Camunda", "Approval routing")
Container(backoffice, "Back Office", "React", "Officer workbench")
ContainerDb(db, "Applications DB", "PostgreSQL", "Applications and decisions")
}
System_Ext(idp, "National Identity", "e-KYC login")
System_Ext(docs, "DigiLocker", "Verified documents")
System_Ext(pay, "Gov Payment Gateway", "Fees and treasury")
Rel(citizen, web, "Uses")
Rel(web, idp, "Logs in via")
Rel(web, api, "Calls", "HTTPS")
Rel(api, apps, "Routes")
Rel(apps, db, "Stores")
Rel(apps, wf, "Starts approval")
Rel(officer, backoffice, "Uses")
Rel(backoffice, wf, "Completes tasks")
Rel(apps, docs, "Fetches documents")
Rel(apps, pay, "Collects fees")Related templates
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