ARCHITECTURE_DECISIONS.md - fineract-backoffice-ui - Git at Google

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 # Architectural Decisions & PM Responses

 As the Technical Architect, here are the strategic responses to the Product Manager's concerns regarding the Fineract Backoffice UI baseline, now updated to include Community Bank specific considerations.

 ---

 ## 1. Data Privacy & Tenant Isolation

 - **Dynamic Resolution:** Tenant ID resolved from hostname or storage, never hardcoded.
 - **Security Enforcement:** Strict injection via `HttpInterceptor` and immutable application state.

 ## 2. Connectivity & Performance (MFI vs. Community Bank)

 - **MFI (Last-Mile):** PWA support with IndexedDB sync queue for offline loan applications.
 - **Community Bank (Scalability):** We will implement a **Virtual Scrolling** and **Server-side Pagination** pattern as the default for all data grids to ensure the UI remains performant when handling community bank-sized datasets.

 ## 3. White Labeling & Configuration-Driven UI

 - **Runtime Theme Injection:** CSS Variables used for branding, loaded from a tenant-specific `branding.json`.
 - **Formly / Dynamic Forms:** Entity forms (Clients, Loans) will be schema-driven to allow vendors to hide/show fields (e.g., "Social Collateral" for MFIs vs "FICO Score" for Banks) without code changes.
 - **Mode-Based Layouts:** The layout engine will support "MFI Mode" (Center/Group centric) vs "Bank Mode" (Individual/Branch centric) via high-level configuration.

 ## 4. Security & Compliance

 - **Local HTTPS:** Automated SSL scaffolding for secure development against remote sandboxes.
 - **Zero Persistence for PII:** Sensitive data kept in-memory (Angular Signals).
 - **Encrypted Storage:** Non-sensitive persistence encrypted via Web Crypto API.

 ## 5. Relationship Management & Domain Schemas

 - **360-View profile:** To support Community Bank relationship banking, the client profile will be designed as a "Composite Resource," aggregating data from Fineract's Clients, Accounts, and Loans APIs into a single dashboard view.

 ## 6. Regulatory & Audit

 - **Telemetry Service:** Scaffolded to log UI-side actions, meeting strict banking audit requirements.
 - **RBAC:** Structural directive `*appHasPermission` to dynamically adapt the UI based on granular Fineract permissions.
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	# Architectural Decisions & PM Responses

	As the Technical Architect, here are the strategic responses to the Product Manager's concerns regarding the Fineract Backoffice UI baseline, now updated to include Community Bank specific considerations.

	---

	## 1. Data Privacy & Tenant Isolation

	- Dynamic Resolution: Tenant ID resolved from hostname or storage, never hardcoded.
	- Security Enforcement: Strict injection via `HttpInterceptor` and immutable application state.

	## 2. Connectivity & Performance (MFI vs. Community Bank)

	- MFI (Last-Mile): PWA support with IndexedDB sync queue for offline loan applications.
	- Community Bank (Scalability): We will implement a Virtual Scrolling and Server-side Pagination pattern as the default for all data grids to ensure the UI remains performant when handling community bank-sized datasets.

	## 3. White Labeling & Configuration-Driven UI

	- Runtime Theme Injection: CSS Variables used for branding, loaded from a tenant-specific `branding.json`.
	- Formly / Dynamic Forms: Entity forms (Clients, Loans) will be schema-driven to allow vendors to hide/show fields (e.g., "Social Collateral" for MFIs vs "FICO Score" for Banks) without code changes.
	- Mode-Based Layouts: The layout engine will support "MFI Mode" (Center/Group centric) vs "Bank Mode" (Individual/Branch centric) via high-level configuration.

	## 4. Security & Compliance

	- Local HTTPS: Automated SSL scaffolding for secure development against remote sandboxes.
	- Zero Persistence for PII: Sensitive data kept in-memory (Angular Signals).
	- Encrypted Storage: Non-sensitive persistence encrypted via Web Crypto API.

	## 5. Relationship Management & Domain Schemas

	- 360-View profile: To support Community Bank relationship banking, the client profile will be designed as a "Composite Resource," aggregating data from Fineract's Clients, Accounts, and Loans APIs into a single dashboard view.

	## 6. Regulatory & Audit

	- Telemetry Service: Scaffolded to log UI-side actions, meeting strict banking audit requirements.
	- RBAC: Structural directive `*appHasPermission` to dynamically adapt the UI based on granular Fineract permissions.