# Product Requirements Document (PRD) - Angular Clarity Boilerplate

## 1. Product Vision

To provide a robust, scalable, and feature-rich boilerplate that serves as a foundational template for building modern, enterprise-grade web applications using Angular and the VMware Clarity Design System. The vision is to accelerate the development lifecycle by offering a pre-configured, best-practice project structure.

## 2. Target Audience

The primary target audience consists of **Angular developers and development teams** who require a standardized, efficient, and consistent starting point for new projects. This includes:

* **Enterprise Development Teams:** Teams that need to maintain a consistent look and feel across multiple applications.
* **Independent Developers:** Individuals looking to quickly bootstrap new projects without spending significant time on initial setup and configuration.

## 3. User Stories (Developer Stories)

### User Story 1: Quick Project Initialization
- **As a developer, I want to clone the repository and run `npm install` and `ng serve` to get a live development server running, so that I can bypass manual setup and start building features immediately.**
- **Acceptance Criteria:**
    - Given I have Node.js and Angular CLI installed,
    - When I clone the repository, install dependencies, and run the start command,
    - Then the application compiles successfully and is accessible in my browser at `localhost:4200`.

### User Story 2: Add a New Feature
- **As a developer, I want to create a new lazy-loaded feature module with its own components and routing, so that I can add new sections to the application in a scalable way.**
- **Acceptance Criteria:**
    - Given the boilerplate is running,
    - When I use the Angular CLI to generate a new module and add it to the main routing configuration,
    - Then I can navigate to the new feature's route, and its components are rendered correctly.

### User Story 3: Utilize Shared Components
- **As a developer, I want to use a component from the `SharedModule` within a new feature module, so that I can reuse common UI elements and maintain consistency.**
- **Acceptance Criteria:**
    - Given I have a new feature module,
    - When I import the `SharedModule` into my feature module,
    - Then I can use the shared components (e.g., a custom card or loader) in my feature's templates without errors.

## 4. Functional Requirements

- **FR-001: Pre-configured Angular Environment:** A ready-to-use Angular CLI project with all necessary dependencies and build configurations.
- **FR-002: Clarity Design System Integration:** Full integration of Clarity UI components and styles, ready for immediate use.
- **FR-003: Scalable Architecture:** A modular structure featuring a `CoreModule` for singleton services and a `SharedModule` for reusable UI components, directives, and pipes.
- **FR-004: Responsive Layout:** A default application shell with a responsive header, navigation sidebar, and main content area.
- **FR-005: Routing:** A pre-configured routing module with examples of lazy-loaded feature modules.
- **FR-006: Theming:** Basic support for Clarity's light and dark themes.

## 5. Non-Functional Requirements

- **NFR-001: Performance:** The initial boilerplate should be lightweight, ensuring fast development server startup times and optimized production builds.
- **NFR-002: Usability (Developer Experience):** The codebase must be clean, well-commented, and logically organized to provide an excellent developer experience.
- **NFR-003: Maintainability:** The modular architecture must facilitate easy updates to dependencies and allow for the addition of new features without introducing breaking changes to the core structure.
- **NFR-004: Scalability:** The architecture is designed to support the growth of large, enterprise-scale applications.
- **NFR-005: Extensibility:** The boilerplate should be easy to customize and extend with additional libraries, modules, and configurations as per project-specific needs.

## 6. Out of Scope

The following features and functionalities are explicitly out of scope for the boilerplate:

-   **Backend Implementation:** This is a frontend-only boilerplate and does not include any backend code or database.
-   **Authentication/Authorization Logic:** While the architecture supports the implementation of security features, no pre-built authentication or authorization logic is included.
-   **State Management:** The boilerplate does not include a state management library (e.g., NgRx, Akita) by default, allowing developers to choose the best solution for their needs.
-   **Business Logic:** No specific business logic or application features are included beyond the basic structural components.
-   **CI/CD Pipelines:** While the project is ready for CI/CD, no pre-configured pipelines are included.

---

## PRD UPDATE - 2025-10-02 06:17:31

## Product Requirements Document (PRD)

### Generated: 2025-10-02T[CURRENT_TIMESTAMP]

## 1. Executive Summary
The Notes App is a full-stack web application designed to provide users with a secure and intuitive platform for managing personal notes. Leveraging an Angular Clarity boilerplate for a modern frontend and a Python Flask backend with PostgreSQL, the application will initially focus on core functionalities including secure user authentication (registration, login, logout) and comprehensive note management (create, view, edit, delete). A subsequent phase will introduce advanced features such as note search, filtering by tags, rich text editing, and a dedicated tagging system to enhance organization and user experience. The primary objective is to deliver a reliable, performant, and user-friendly note-taking solution.

## 2. Product Vision & Strategy
**Product Vision:** To be the most trusted and intuitive digital companion for individuals seeking to securely capture, organize, and access their thoughts and information anytime, anywhere.

**Strategic Goals:**
*   Achieve high user satisfaction with core note-taking functionalities and authentication.
*   Ensure robust data security and privacy for all user notes.
*   Provide an efficient and scalable platform that supports growth in users and note volume.
*   Deliver a consistent and accessible user experience across various devices.
*   Enable advanced organizational capabilities to transform basic notes into an intelligent knowledge base.

**Success Metrics (KPIs):**
*   **User Adoption:** Number of registered users, percentage of successful logins.
*   **Engagement:** Average number of notes created per user per week, daily/monthly active users.
*   **Retention:** User churn rate over time.
*   **Performance:** Average note load time, search query response time, note save duration (as per NFRs).
*   **Security:** Number of reported security vulnerabilities (target zero), successful audit compliance.

## 3. Target Users & Personas
**Target Users:** Individuals, students, and professionals who need a reliable, secure, and easy-to-use digital platform to jot down ideas, organize information, and keep track of personal or work-related notes.

**Persona: "Olivia the Organized Student"**
*   **Demographics:** 22-year-old university student, tech-savvy, uses multiple devices (laptop, tablet, phone).
*   **Needs:** Needs a centralized place to store lecture notes, research snippets, and to-do lists. Requires quick access, easy organization (tags are a must), and the ability to format notes for better readability. Security is important for personal research.
*   **Pain Points:** Current solutions are either too complex, lack proper organizational features, or are not accessible across all her devices. Worries about privacy of her academic notes.
*   **Goals:** Efficiently take and organize notes for multiple courses, easily retrieve information for exams, and collaborate on study materials (future consideration).
*   **Scenario:** Olivia attends a lecture, quickly opens the Notes App on her tablet to type notes, adding tags like "Biology," "Lecture 3," and "Exam Prep." Later, she reviews the notes on her laptop, adding bolding to key terms and creating bullet lists for summaries. She then searches for "DNA replication" to quickly find all relevant notes before her exam.

## 4. Problem Statement
Users often struggle to find a single, cohesive, and secure platform that effectively combines basic note-taking functionality with advanced organizational features. Existing solutions may compromise on security, lack intuitive interfaces, or fail to provide robust tools for searching, filtering, and rich text formatting, leading to fragmented information, wasted time, and a reduced ability to leverage their personal knowledge base.

## 5. Solution Overview
The Notes App will be a full-stack web application providing a secure and versatile environment for personal note management. The frontend, built on Angular with the Clarity Design System, will offer a modern, responsive, and intuitive user interface. The backend, developed with Python Flask and leveraging PostgreSQL, will provide a robust RESTful API for secure user authentication, note CRUD operations, and managing advanced features like tagging, search, and rich text content. The solution aims to simplify personal information management by offering a secure, organized, and easily accessible digital notebook.

## 6. Functional Requirements
*   **FR-001: User Registration:** Allow new users to create an account with a unique username and a strong password, storing credentials securely.
*   **FR-002: User Login:** Enable registered users to authenticate using their username and password, granting access to their personal notes.
*   **FR-003: User Logout:** Provide a mechanism for users to securely terminate their session.
*   **FR-004: Create Note:** Allow authenticated users to create new notes, specifying a title and rich text content.
*   **FR-005: View Notes List:** Display a paginated/scrollable list of all notes belonging to the authenticated user, showing titles and content snippets. Allow for sorting (e.g., by creation date).
*   **FR-006: View Note Detail:** Enable users to view the full title and rich text content of a specific note.
*   **FR-007: Edit Note:** Allow users to modify the title and rich text content of an existing note.
*   **FR-008: Delete Note:** Provide functionality for users to permanently delete their notes with a confirmation step.
*   **FR-009: Search Notes:** Enable users to search their notes by keywords present in the title or content.
*   **FR-010: Filter Notes:** Allow users to filter their notes based on criteria such as assigned tags or creation/modification date ranges.
*   **FR-011: Rich Text Editing:** Integrate a rich text editor (WYSIWYG) for note content, enabling formatting options (e.g., bold, italics, lists, headings).
*   **FR-012: Add/Manage Tags:** Provide functionality to assign, view, and remove multiple user-defined tags to/from a note.
*   **FR-013: Unique Username Enforcement:** The system shall ensure that each registered user has a unique username.
*   **FR-014: Password Complexity Enforcement:** The system shall validate user passwords against a defined complexity policy during registration and password updates.
*   **FR-015: User Data Segregation:** The system shall ensure that a user can only access, modify, or delete their own notes and tags.

## 7. Non-Functional Requirements
*   **NFR-001: Performance:**
    *   Application startup time (first paint) should be under 3 seconds on a standard broadband connection.
    *   Note list retrieval should complete within 2 seconds for up to 100 notes.
    *   Individual note retrieval/save operations should complete within 1 second.
    *   Search and filter operations should return results within 3 seconds for up to 100,000 notes per user.
*   **NFR-002: Security:**
    *   User passwords shall be securely hashed using bcrypt (or similar strong algorithm) and salted before storage.
    *   Authentication shall use JWTs for API authorization, with short-lived access tokens.
    *   All data transfer (frontend to backend) shall be encrypted via HTTPS/TLS.
    *   Access control mechanisms shall strictly enforce note ownership (a user can only interact with their own notes).
    *   API endpoints shall implement rate limiting for authentication attempts (e.g., 5 attempts per minute per IP).
    *   All input fields, especially rich text content, shall be sanitized on both frontend and backend to prevent XSS, SQL injection, and other vulnerabilities.
*   **NFR-003: Usability (Developer Experience from boilerplate, User Experience for app):**
    *   The application interface shall be intuitive and easy to navigate, following the VMware Clarity Design System guidelines.
    *   Clear and concise feedback messages (success, error, loading states) shall be provided for all user actions.
    *   The UI shall be fully responsive, adapting to various screen sizes (desktop, tablet, mobile).
*   **NFR-004: Maintainability:**
    *   The codebase shall adhere to established Angular and Flask best practices, including modularization, clear component structure, and consistent naming conventions.
    *   Comprehensive inline code comments and documentation shall be provided for complex logic and API endpoints.
    *   Unit and integration tests shall cover critical functionalities (Auth, Note CRUD).
*   **NFR-005: Scalability:**
    *   The backend architecture (Flask with PostgreSQL, stateless JWT) shall support horizontal scaling of API instances.
    *   Database schema design (indexing on `userId`, `createdAt`, `title`, `content` for search) shall accommodate up to 100,000 notes per user and 10,000 concurrent users without significant performance degradation.
    *   Lazy loading of Angular modules will ensure frontend performance as the application grows.
*   **NFR-006: Data Integrity:**
    *   All critical user and note data shall be persisted in PostgreSQL with appropriate foreign key constraints and transaction management to ensure consistency and accuracy.
    *   Backup and recovery procedures for the database shall be established (infrastructure-level concern, but noted).

## 8. Epic Stories

### Epic 1: User Authentication & Account Management (Phase 1 MVP)
**Epic Description:** This epic covers all functionalities related to user account creation, secure login, and session management, ensuring that users can safely access their personalized notes.
**Business Value:** Enables multi-user functionality and personalized note storage, a foundational requirement for any secure note-taking application.
**Acceptance Criteria:** Users can successfully register, log in, and log out securely, and only access their own notes.

**User Stories:**
-   **US-001:** Register for an account
    -   **As a** new user
    -   **I want to** register for an account with a unique username and strong password
    -   **So that** I can securely store my personal notes.
    -   **Acceptance Criteria:**
        -   [ ] Given I am on the application's landing page, when I click on a "Register" button, then I am presented with a registration form requiring a username and password.
        -   [ ] When I enter a unique username and a strong password (min 8 chars, mixed case, number, special char) and click "Submit", then my account is created, and I am either logged in or redirected to the login page.
        -   [ ] Given I try to register with an already existing username, then the system prevents registration and informs me that the username is taken.
    -   **Story Points:** 8
    -   **Priority:** High

-   **US-002:** Log into my account
    -   **As a** registered user
    -   **I want to** log into my account
    -   **So that** I can access my notes.
    -   **Acceptance Criteria:**
        -   [ ] Given I am on the login page, when I enter my correct username and password and click "Login", then I am successfully authenticated and redirected to my notes list.
        -   [ ] Given I enter incorrect credentials, then the system displays an error message "Invalid username or password."
    -   **Story Points:** 5
    -   **Priority:** High

-   **US-003:** Log out of my account
    -   **As a** registered user
    -   **I want to** securely log out of my account
    -   **So that** my session is terminated and my notes are protected.
    -   **Acceptance Criteria:**
        -   [ ] Given I am logged into the application, when I click on a "Logout" button/link, then my session is terminated, and I am redirected to the login page.
    -   **Story Points:** 3
    -   **Priority:** High

### Epic 2: Core Note Management (CRUD) (Phase 1 MVP)
**Epic Description:** This epic focuses on the fundamental operations required for managing individual notes, including creation, viewing, updating, and deletion.
**Business Value:** Provides the primary utility of a note-taking application, allowing users to capture and manage their information.
**Acceptance Criteria:** Users can perform all basic CRUD operations on their notes, and changes are persisted and reflected accurately.

**User Stories:**
-   **US-004:** Create a new note
    -   **As a** registered user
    -   **I want to** create a new note with a title and content
    -   **So that** I can capture my thoughts and information.
    -   **Acceptance Criteria:**
        -   [ ] Given I am logged in and on the notes list page, when I click the "New Note" button, then I am presented with a form to enter a title and content.
        -   [ ] When I enter a title (minimum 1 character) and optional content and click "Save", then the note is saved, and I see it in my notes list.
        -   [ ] I receive a confirmation message that the note was created.
    -   **Story Points:** 5
    -   **Priority:** High

-   **US-005:** View all my notes
    -   **As a** registered user
    -   **I want to** see a list of all my existing notes
    -   **So that** I can quickly browse and select them.
    -   **Acceptance Criteria:**
        -   [ ] Given I am logged in and on the notes list page, when the page loads, then I see a list of my notes, each displaying its title and a snippet of its content.
        -   [ ] The list is ordered by creation date (newest first) by default.
        -   [ ] The list supports pagination or infinite scroll for many notes.
    -   **Story Points:** 5
    -   **Priority:** High

-   **US-006:** View a single note's details
    -   **As a** registered user
    -   **I want to** view the full content of a specific note
    -   **So that** I can review it in detail.
    -   **Acceptance Criteria:**
        -   [ ] Given I am on the notes list page, when I click on a note's title or entry, then I am navigated to a page displaying the full title and content of that note.
    -   **Story Points:** 3
    -   **Priority:** High

-   **US-007:** Edit an existing note
    -   **As a** registered user
    -   **I want to** modify an existing note's title or content
    -   **So that** I can update my information.
    -   **Acceptance Criteria:**
        -   [ ] Given I am viewing a single note, when I click an "Edit" button, then the note's title and content become editable within a form (with rich text editor).
        -   [ ] When I make changes to the title or content and click "Save", then the note is updated, and I see the updated content.
        -   [ ] I receive a confirmation message that the note was updated.
    -   **Story Points:** 8
    -   **Priority:** High

-   **US-008:** Delete a note
    -   **As a** registered user
    -   **I want to** remove a note that is no longer needed
    -   **So that** my notes list remains organized and clutter-free.
    -   **Acceptance Criteria:**
        -   [ ] Given I am viewing a single note or on the notes list page, when I click a "Delete" button for a note, then I am presented with a confirmation dialog.
        -   [ ] When I confirm the deletion, then the note is permanently removed from my list.
        -   [ ] I receive a confirmation message that the note was deleted.
    -   **Story Points:** 5
    -   **Priority:** High

### Epic 3: Advanced Note Organization & Editing (Phase 2)
**Epic Description:** This epic focuses on enhancing the note-taking experience with powerful features for organizing, finding, and formatting notes, moving beyond basic CRUD to intelligent knowledge management.
**Business Value:** Significantly improves user productivity and satisfaction by enabling efficient information retrieval and expressive content creation.
**Acceptance Criteria:** Users can effectively search, filter, tag, and format their notes, making their information more accessible and readable.

**User Stories:**
-   **US-009:** Search my notes by keywords
    -   **As a** user
    -   **I want to** search my notes by keywords in their title or content
    -   **So that** I can quickly find specific information.
    -   **Acceptance Criteria:**
        -   [ ] Given I am viewing my notes list, when I type keywords into a search bar and press Enter (or click Search), then the notes list updates to show only notes whose title or content contains the entered keywords (case-insensitive).
        -   [ ] The search results highlight the matching keywords.
    -   **Story Points:** 8
    -   **Priority:** Medium

-   **US-010:** Filter my notes by assigned tags
    -   **As a** user
    -   **I want to** filter my notes by assigned tags
    -   **So that** I can organize and view related notes together.
    -   **Acceptance Criteria:**
        -   [ ] Given I am viewing my notes list, when I select one or more tags from a filter option (e.g., a dropdown or tag cloud), then the notes list is filtered to show only notes containing all selected tags.
        -   [ ] The filter can be cleared to show all notes again.
    -   **Story Points:** 8
    -   **Priority:** Medium

-   **US-011:** Apply rich text formatting to note content
    -   **As a** user
    -   **I want to** apply basic formatting to my note content (e.g., bold, italics, lists, headings)
    -   **So that** my notes are more readable and organized.
    -   **Acceptance Criteria:**
        -   [ ] Given I am creating or editing a note, when I use the rich text editor's toolbar options, then the selected text or new input is formatted accordingly.
        -   [ ] The formatted content is correctly saved and displayed when viewing the note.
        -   [ ] The rich text editor should prevent known XSS vulnerabilities through sanitization.
    -   **Story Points:** 13
    -   **Priority:** Medium

-   **US-012:** Add and manage tags for my notes
    -   **As a** user
    -   **I want to** assign multiple tags to my notes
    -   **So that** I can categorize them for easier retrieval and filtering.
    -   **Acceptance Criteria:**
        -   [ ] Given I am creating or editing a note, when I interact with a tag input field (e.g., type a tag name and press Enter, or select from existing tags), then the tag is added to the note.
        -   [ ] Tags associated with a note are clearly displayed in the note detail and potentially the list view.
        -   [ ] I can remove tags from a note.
        -   [ ] (Stretch) I can view and manage all my available tags (create new, delete old).
    -   **Story Points:** 8
    -   **Priority:** Medium

## 9. User Interface Requirements
*   **Clarity Design System Adherence:** The UI must strictly adhere to the VMware Clarity Design System for components, typography, colors, and overall visual language, ensuring a consistent and professional look and feel.
*   **Responsive Design:** The application must be fully responsive, providing an optimal viewing and interaction experience across various devices and screen sizes (desktop, tablet, mobile).
*   **Intuitive Navigation:** Clear navigation paths for accessing notes, authentication forms, and future settings. A persistent header and side navigation (from the boilerplate) will be utilized.
*   **Form Design:** All input forms (registration, login, create/edit note) should be clear, user-friendly, and provide real-time validation feedback.
*   **Feedback & Notifications:** Implement clear visual feedback for user actions (e.g., loading indicators, success messages, error alerts, confirmation dialogs).
*   **Accessibility:** Adhere to WCAG (Web Content Accessibility Guidelines) where possible, leveraging Clarity's built-in accessibility features to ensure the application is usable by individuals with disabilities.

## 10. Technical Requirements
*   **Frontend Technologies (Angular, TypeScript, Clarity):** The frontend will leverage Angular 16+, TypeScript, and the Clarity Design System as established by the boilerplate. RxJS will be used for reactive programming, and Angular's HttpClient for API communication. A rich text editor library (`@ckeditor/ckeditor5-angular` or similar) will be integrated for US-011.
*   **Backend Technologies (Python Flask, PostgreSQL):** The backend will be developed with Python 3.9+ using the Flask microframework to expose RESTful API endpoints. Gunicorn will serve the application. PostgreSQL will be the primary database, accessed via SQLAlchemy with Flask-SQLAlchemy.
*   **API Design:** A RESTful API will be designed with clear resource-based URLs and standard HTTP methods (GET, POST, PUT, DELETE). JSON will be the primary data exchange format. All user-specific operations will require JWT-based authentication.
*   **Authentication & Authorization:** Implement JWT for stateless authentication. Passwords will be securely hashed (e.g., bcrypt). Backend API endpoints will enforce authorization, ensuring users can only access their own data. HTTPS will secure all data in transit.
*   **Data Model:** The database will include `User`, `Note`, and `Tag` entities with appropriate relationships (`User` 1:N `Note`, `Note` M:N `Tag` via `Note_Tag` join table), as detailed in `architecture_document.md`.
*   **Input Validation & Sanitization:** Rigorous input validation will be implemented on both frontend and backend. Backend will sanitize all rich text content to prevent XSS.
*   **Containerization:** Both frontend and backend applications will be containerized using Docker, enabling consistent development and deployment environments. Docker Compose will be used for local multi-service orchestration.

## 11. Success Metrics & KPIs
*   **Registration Rate:** Percentage of visitors who complete user registration.
*   **Active User Rate (DAU/MAU):** Number of daily/monthly active users logging in and performing actions.
*   **Notes Created per User:** Average number of notes created by active users over a period.
*   **Note Retrieval Speed:** Average time taken to load the notes list and individual notes (should meet NFR-001).
*   **Search/Filter Usage:** Percentage of active users utilizing search and filter functionalities.
*   **Error Rate:** Number of backend API errors or frontend critical errors (aim for <0.1%).
*   **Security Vulnerabilities:** Number of identified and remediated critical/high-severity vulnerabilities.
*   **Uptime:** Percentage of time the application is available to users.

## 12. Risk Assessment
*   **R1: Security Vulnerabilities:** Risk of data breaches or unauthorized access due to flawed authentication/authorization or injection vulnerabilities.
    *   **Mitigation:** Implement robust security practices (bcrypt, JWT, HTTPS, input sanitization, rate limiting), regular security audits, and follow secure coding guidelines. Frontend and backend validation are critical.
*   **R2: Scope Creep:** Tendency to add more features beyond the MVP, delaying delivery.
    *   **Mitigation:** Strict adherence to the phased approach, clear MVP definition, ruthless prioritization, and continuous review of requirements against business value.
*   **R3: Performance Bottlenecks:** Slow load times or unresponsive UI, especially with large numbers of notes or concurrent users.
    *   **Mitigation:** Database indexing, optimized API queries, efficient frontend rendering (lazy loading, virtual scroll), caching (future consideration), and load testing.
*   **R4: Rich Text Editor Integration Complexity:** Challenges in integrating a third-party rich text editor, handling its data (HTML/Markdown), and ensuring security (XSS prevention).
    *   **Mitigation:** Thorough evaluation of editor libraries, careful implementation of content sanitization, and dedicated testing for formatting and security.
*   **R5: Backend-Frontend Integration Issues:** Mismatches in API contracts, authentication flows, or data serialization.
    *   **Mitigation:** Early and continuous communication between frontend and backend teams, clear API documentation (Swagger/OpenAPI), and integration testing.
*   **R6: Database Scalability:** Performance degradation with a very large number of users/notes.
    *   **Mitigation:** Proactive database tuning, appropriate indexing, and consideration of sharding or other scaling strategies for future growth.

## 13. Timeline & Milestones
**Phase 1: Minimum Viable Product (MVP) - Core Features (Estimated: 4-6 Sprints)**
*   **Sprint 1-2: Setup & Authentication Foundation**
    *   Backend: Flask API for User Registration & Login (JWT integration, password hashing, DB schema for Users).
    *   Frontend: Angular Auth Module (Register/Login components, AuthGuard, Auth Service).
    *   **Milestone:** M1.1 (Backend Auth API Complete), M1.2 (Frontend Auth UI/Integration Complete)
*   **Sprint 3-4: Core Notes CRUD**
    *   Backend: Flask API for Notes CRUD (DB schema for Notes, User-Note relationship, authorization).
    *   Frontend: Angular Notes Module (Notes List, Note Detail, Note Editor components for basic text, integration with Notes API).
    *   **Milestone:** M1.3 (Backend Notes CRUD API Complete), M1.4 (Frontend Notes CRUD UI/Integration Complete)
*   **Sprint 5-6: MVP Polish & Testing**
    *   Refine UI/UX for core features, implement feedback messages, unit/integration testing, bug fixing.
    *   **Milestone:** M1.5 (End-to-End MVP Tested & Ready)

**Phase 2: Enhanced Features (Estimated: 4-6 Sprints)**
*   **Sprint 7-8: Search & Filter Integration**
    *   Backend: Extend Notes API for keyword search, filter by tag, (DB indexing for search).
    *   Frontend: Implement search bar, filter UI (tag selection), update Notes List to reflect results.
    *   **Milestone:** M2.1 (Backend Search/Filter/Tagging API Complete - initial)
*   **Sprint 9-10: Rich Text & Tagging System**
    *   Backend: Extend Notes API for tag management (DB schema for Tags & Note_Tag join table), support rich text content storage.
    *   Frontend: Integrate Rich Text Editor (`@ckeditor/ckeditor5-angular`), implement tag input/display components in Note Editor.
    *   **Milestone:** M2.2 (Frontend Search/Filter/Tagging UI/Integration Complete)
*   **Sprint 11-12: Advanced Features Polish & Testing**
    *   Refine UI/UX for advanced features, comprehensive testing, performance optimization, bug fixing.
    *   **Milestone:** M2.3 (End-to-End Enhanced Features Tested & Ready)

## 14. Dependencies & Assumptions
*   **D1: Base Project Stability:** The Angular Clarity boilerplate provides a stable and functional frontend foundation that can be extended without significant refactoring.
*   **D2: Backend API Availability:** Backend API endpoints will be developed concurrently and available for frontend integration as per the phased timeline.
*   **D3: Third-Party Libraries:** Stability and compatibility of chosen third-party libraries (e.g., rich text editor, JWT library, ORM) for both frontend and backend.
*   **D4: Development Environment:** All developers have access to a consistent development environment (e.g., Docker).
*   **A1: Team Expertise:** The development team has sufficient expertise in Angular, Python Flask, PostgreSQL, and security best practices.
*   **A2: API Contract:** Clear API contracts (request/response schemas) will be defined and adhered to by both frontend and backend teams.
*   **A3: Security Audits:** Security audits will be performed periodically to identify and address vulnerabilities.
*   **A4: Iterative Feedback:** Agile processes will allow for continuous feedback and adaptation of requirements.


---

## PRD UPDATE - 2025-10-02 06:20:30

# Product Requirements Document (PRD)

## Generated: 2025-10-02T06:16:00.000000

## 1. Executive Summary
The Notes App is a full-stack web application designed to provide users with a secure and intuitive platform for managing personal notes. Leveraging an Angular Clarity boilerplate for a modern frontend and a Python Flask backend with PostgreSQL, the application will initially focus on core functionalities including secure user authentication (registration, login, logout) and comprehensive note management (create, view, edit, delete). A subsequent phase will introduce advanced features such as note search, filtering by tags, rich text editing, and a dedicated tagging system to enhance organization and user experience. The primary objective is to deliver a reliable, performant, and user-friendly note-taking solution.

## 2. Product Vision & Strategy
**Product Vision:** To be the most trusted and intuitive digital companion for individuals seeking to securely capture, organize, and access their thoughts and information anytime, anywhere.

**Strategic Goals:**
*   Achieve high user satisfaction with core note-taking functionalities and authentication.
*   Ensure robust data security and privacy for all user notes.
*   Provide an efficient and scalable platform that supports growth in users and note volume.
*   Deliver a consistent and accessible user experience across various devices.
*   Enable advanced organizational capabilities to transform basic notes into an intelligent knowledge base.

**Success Metrics (KPIs):**
*   **User Adoption:** Number of registered users, percentage of successful logins.
*   **Engagement:** Average number of notes created per user per week, daily/monthly active users.
*   **Retention:** User churn rate over time.
*   **Performance:** Average note load time, search query response time, note save duration (as per NFRs).
*   **Security:** Number of reported security vulnerabilities (target zero), successful audit compliance.

## 3. Target Users & Personas
**Target Users:** Individuals, students, and professionals who need a reliable, secure, and easy-to-use digital platform to jot down ideas, organize information, and keep track of personal or work-related notes.

**Persona: "Olivia the Organized Student"**
*   **Demographics:** 22-year-old university student, tech-savvy, uses multiple devices (laptop, tablet, phone).
*   **Needs:** Needs a centralized place to store lecture notes, research snippets, and to-do lists. Requires quick access, easy organization (tags are a must), and the ability to format notes for better readability. Security is important for personal research.
*   **Pain Points:** Current solutions are either too complex, lack proper organizational features, or are not accessible across all her devices. Worries about privacy of her academic notes.
*   **Goals:** Efficiently take and organize notes for multiple courses, easily retrieve information for exams, and collaborate on study materials (future consideration).
*   **Scenario:** Olivia attends a lecture, quickly opens the Notes App on her tablet to type notes, adding tags like "Biology," "Lecture 3," and "Exam Prep." Later, she reviews the notes on her laptop, adding bolding to key terms and creating bullet lists for summaries. She then searches for "DNA replication" to quickly find all relevant notes before her exam.

## 4. Problem Statement
Users often struggle to find a single, cohesive, and secure platform that effectively combines basic note-taking functionality with advanced organizational features. Existing solutions may compromise on security, lack intuitive interfaces, or fail to provide robust tools for searching, filtering, and rich text formatting, leading to fragmented information, wasted time, and a reduced ability to leverage their personal knowledge base.

## 5. Solution Overview
The Notes App will be a full-stack web application providing a secure and versatile environment for personal note management. The frontend, built on Angular with the Clarity Design System, will offer a modern, responsive, and intuitive user interface. The backend, developed with Python Flask and leveraging PostgreSQL, will provide a robust RESTful API for secure user authentication, note CRUD operations, and managing advanced features like tagging, search, and rich text content. The solution aims to simplify personal information management by offering a secure, organized, and easily accessible digital notebook.

## 6. Functional Requirements
*   **FR-001: User Registration:** Allow new users to create an account with a unique username and a strong password, storing credentials securely.
*   **FR-002: User Login:** Enable registered users to authenticate using their username and password, granting access to their personal notes.
*   **FR-003: User Logout:** Provide a mechanism for users to securely terminate their session.
*   **FR-004: Create Note:** Allow authenticated users to create new notes, specifying a title and rich text content.
*   **FR-005: View Notes List:** Display a paginated/scrollable list of all notes belonging to the authenticated user, showing titles and content snippets. Allow for sorting (e.g., by creation date).
*   **FR-006: View Note Detail:** Enable users to view the full title and rich text content of a specific note.
*   **FR-007: Edit Note:** Allow users to modify the title and rich text content of an existing note.
*   **FR-008: Delete Note:** Provide functionality for users to permanently delete their notes with a confirmation step.
*   **FR-009: Search Notes:** Enable users to search their notes by keywords present in the title or content.
*   **FR-010: Filter Notes:** Allow users to filter their notes based on criteria such as assigned tags or creation/modification date ranges.
*   **FR-011: Rich Text Editing:** Integrate a rich text editor (WYSIWYG) for note content, enabling formatting options (e.g., bold, italics, lists, headings).
*   **FR-012: Add/Manage Tags:** Provide functionality to assign, view, and remove multiple user-defined tags to/from a note.
*   **FR-013: Unique Username Enforcement:** The system shall ensure that each registered user has a unique username.
*   **FR-014: Password Complexity Enforcement:** The system shall validate user passwords against a defined complexity policy during registration and password updates.
*   **FR-015: User Data Segregation:** The system shall ensure that a user can only access, modify, or delete their own notes and tags.

## 7. Non-Functional Requirements
*   **NFR-001: Performance:**
    *   Application startup time (first paint) should be under 3 seconds on a standard broadband connection.
    *   Note list retrieval should complete within 2 seconds for up to 100 notes.
    *   Individual note retrieval/save operations should complete within 1 second.
    *   Search and filter operations should return results within 3 seconds for up to 100,000 notes per user.
*   **NFR-002: Security:**
    *   User passwords shall be securely hashed using bcrypt (or similar strong algorithm) and salted before storage.
    *   Authentication shall use JWTs for API authorization, with short-lived access tokens.
    *   All data transfer (frontend to backend) shall be encrypted via HTTPS/TLS.
    *   Access control mechanisms shall strictly enforce note ownership (a user can only interact with their own notes).
    *   API endpoints shall implement rate limiting for authentication attempts (e.g., 5 attempts per minute per IP).
    *   All input fields, especially rich text content, shall be sanitized on both frontend and backend to prevent XSS, SQL injection, and other vulnerabilities.
*   **NFR-003: Usability (Developer Experience from boilerplate, User Experience for app):**
    *   The application interface shall be intuitive and easy to navigate, following the VMware Clarity Design System guidelines.
    *   Clear and concise feedback messages (success, error, loading states) shall be provided for all user actions.
    *   The UI shall be fully responsive, adapting to various screen sizes (desktop, tablet, mobile).
*   **NFR-004: Maintainability:**
    *   The codebase shall adhere to established Angular and Flask best practices, including modularization, clear component structure, and consistent naming conventions.
    *   Comprehensive inline code comments and documentation shall be provided for complex logic and API endpoints.
    *   Unit and integration tests shall cover critical functionalities (Auth, Note CRUD).
*   **NFR-005: Scalability:**
    *   The backend architecture (Flask with PostgreSQL, stateless JWT) shall support horizontal scaling of API instances.
    *   Database schema design (indexing on `userId`, `createdAt`, `title`, `content` for search) shall accommodate up to 100,000 notes per user and 10,000 concurrent users without significant performance degradation.
    *   Lazy loading of Angular modules will ensure frontend performance as the application grows.
*   **NFR-006: Data Integrity:**
    *   All critical user and note data shall be persisted in PostgreSQL with appropriate foreign key constraints and transaction management to ensure consistency and accuracy.
    *   Backup and recovery procedures for the database shall be established (infrastructure-level concern, but noted).

## 8. Epic Stories

### Epic 1: User Authentication & Account Management (Phase 1 MVP)
**Epic Description:** This epic covers all functionalities related to user account creation, secure login, and session management, ensuring that users can safely access their personalized notes.
**Business Value:** Enables multi-user functionality and personalized note storage, a foundational requirement for any secure note-taking application.
**Acceptance Criteria:** Users can successfully register, log in, and log out securely, and only access their own notes.

**User Stories:**
-   **US-001:** Register for an account
    -   **As a** new user
    -   **I want to** register for an account with a unique username and strong password
    -   **So that** I can securely store my personal notes.
    -   **Acceptance Criteria:**
        -   [ ] Given I am on the application's landing page, when I click on a "Register" button, then I am presented with a registration form requiring a username and password.
        -   [ ] When I enter a unique username and a strong password (min 8 chars, mixed case, number, special char) and click "Submit", then my account is created, and I am either logged in or redirected to the login page.
        -   [ ] Given I try to register with an already existing username, then the system prevents registration and informs me that the username is taken.
    -   **Story Points:** 8
    -   **Priority:** High

-   **US-002:** Log into my account
    -   **As a** registered user
    -   **I want to** log into my account
    -   **So that** I can access my notes.
    -   **Acceptance Criteria:**
        -   [ ] Given I am on the login page, when I enter my correct username and password and click "Login", then I am successfully authenticated and redirected to my notes list.
        -   [ ] Given I enter incorrect credentials, then the system displays an error message "Invalid username or password."
    -   **Story Points:** 5
    -   **Priority:** High

-   **US-003:** Log out of my account
    -   **As a** registered user
    -   **I want to** securely log out of my account
    -   **So that** my session is terminated and my notes are protected.
    -   **Acceptance Criteria:**
        -   [ ] Given I am logged into the application, when I click on a "Logout" button/link, then my session is terminated, and I am redirected to the login page.
    -   **Story Points:** 3
    -   **Priority:** High

### Epic 2: Core Note Management (CRUD) (Phase 1 MVP)
**Epic Description:** This epic focuses on the fundamental operations required for managing individual notes, including creation, viewing, updating, and deletion.
**Business Value:** Provides the primary utility of a note-taking application, allowing users to capture and manage their information.
**Acceptance Criteria:** Users can perform all basic CRUD operations on their notes, and changes are persisted and reflected accurately.

**User Stories:**
-   **US-004:** Create a new note
    -   **As a** registered user
    -   **I want to** create a new note with a title and content
    -   **So that** I can capture my thoughts and information.
    -   **Acceptance Criteria:**
        -   [ ] Given I am logged in and on the notes list page, when I click the "New Note" button, then I am presented with a form to enter a title and content.
        -   [ ] When I enter a title (minimum 1 character) and optional content and click "Save", then the note is saved, and I see it in my notes list.
        -   [ ] I receive a confirmation message that the note was created.
    -   **Story Points:** 5
    -   **Priority:** High

-   **US-005:** View all my notes
    -   **As a** registered user
    -   **I want to** see a list of all my existing notes
    -   **So that** I can quickly browse and select them.
    -   **Acceptance Criteria:**
        -   [ ] Given I am logged in and on the notes list page, when the page loads, then I see a list of my notes, each displaying its title and a snippet of its content.
        -   [ ] The list is ordered by creation date (newest first) by default.
        -   [ ] The list supports pagination or infinite scroll for many notes.
    -   **Story Points:** 5
    -   **Priority:** High

-   **US-006:** View a single note's details
    -   **As a** registered user
    -   **I want to** view the full content of a specific note
    -   **So that** I can review it in detail.
    -   **Acceptance Criteria:**
        -   [ ] Given I am on the notes list page, when I click on a note's title or entry, then I am navigated to a page displaying the full title and content of that note.
    -   **Story Points:** 3
    -   **Priority:** High

-   **US-007:** Edit an existing note
    -   **As a** registered user
    -   **I want to** modify an existing note's title or content
    -   **So that** I can update my information.
    -   **Acceptance Criteria:**
        -   [ ] Given I am viewing a single note, when I click an "Edit" button, then the note's title and content become editable within a form (with rich text editor).
        -   [ ] When I make changes to the title or content and click "Save", then the note is updated, and I see the updated content.
        -   [ ] I receive a confirmation message that the note was updated.
    -   **Story Points:** 8
    -   **Priority:** High

-   **US-008:** Delete a note
    -   **As a** registered user
    -   **I want to** remove a note that is no longer needed
    -   **So that** my notes list remains organized and clutter-free.
    -   **Acceptance Criteria:**
        -   [ ] Given I am viewing a single note or on the notes list page, when I click a "Delete" button for a note, then I am presented with a confirmation dialog.
        -   [ ] When I confirm the deletion, then the note is permanently removed from my list.
        -   [ ] I receive a confirmation message that the note was deleted.
    -   **Story Points:** 5
    -   **Priority:** High

### Epic 3: Advanced Note Organization & Editing (Phase 2)
**Epic Description:** This epic focuses on enhancing the note-taking experience with powerful features for organizing, finding, and formatting notes, moving beyond basic CRUD to intelligent knowledge management.
**Business Value:** Significantly improves user productivity and satisfaction by enabling efficient information retrieval and expressive content creation.
**Acceptance Criteria:** Users can effectively search, filter, tag, and format their notes, making their information more accessible and readable.

**User Stories:**
-   **US-009:** Search my notes by keywords
    -   **As a** user
    -   **I want to** search my notes by keywords in their title or content
    -   **So that** I can quickly find specific information.
    -   **Acceptance Criteria:**
        -   [ ] Given I am viewing my notes list, when I type keywords into a search bar and press Enter (or click Search), then the notes list updates to show only notes whose title or content contains the entered keywords (case-insensitive).
        -   [ ] The search results highlight the matching keywords.
    -   **Story Points:** 8
    -   **Priority:** Medium

-   **US-010:** Filter my notes by assigned tags
    -   **As a** user
    -   **I want to** filter my notes by assigned tags
    -   **So that** I can organize and view related notes together.
    -   **Acceptance Criteria:**
        -   [ ] Given I am viewing my notes list, when I select one or more tags from a filter option (e.g., a dropdown or tag cloud), then the notes list is filtered to show only notes containing all selected tags.
        -   [ ] The filter can be cleared to show all notes again.
    -   **Story Points:** 8
    -   **Priority:** Medium

-   **US-011:** Apply rich text formatting to note content
    -   **As a** user
    -   **I want to** apply basic formatting to my note content (e.g., bold, italics, lists, headings)
    -   **So that** my notes are more readable and organized.
    -   **Acceptance Criteria:**
        -   [ ] Given I am creating or editing a note, when I use the rich text editor's toolbar options, then the selected text or new input is formatted accordingly.
        -   [ ] The formatted content is correctly saved and displayed when viewing the note.
        -   [ ] The rich text editor should prevent known XSS vulnerabilities through sanitization.
    -   **Story Points:** 13
    -   **Priority:** Medium

-   **US-012:** Add and manage tags for my notes
    -   **As a** user
    -   **I want to** assign multiple tags to my notes
    -   **So that** I can categorize them for easier retrieval and filtering.
    -   **Acceptance Criteria:**
        -   [ ] Given I am creating or editing a note, when I interact with a tag input field (e.g., type a tag name and press Enter, or select from existing tags), then the tag is added to the note.
        -   [ ] Tags associated with a note are clearly displayed in the note detail and potentially the list view.
        -   [ ] I can remove tags from a note.
        -   [ ] (Stretch) I can view and manage all my available tags (create new, delete old).
    -   **Story Points:** 8
    -   **Priority:** Medium

## 9. User Interface Requirements
*   **Clarity Design System Adherence:** The UI must strictly adhere to the VMware Clarity Design System for components, typography, colors, and overall visual language, ensuring a consistent and professional look and feel.
*   **Responsive Design:** The application must be fully responsive, providing an optimal viewing and interaction experience across various devices and screen sizes (desktop, tablet, mobile).
*   **Intuitive Navigation:** Clear navigation paths for accessing notes, authentication forms, and future settings. A persistent header and side navigation (from the boilerplate) will be utilized.
*   **Form Design:** All input forms (registration, login, create/edit note) should be clear, user-friendly, and provide real-time validation feedback.
*   **Feedback & Notifications:** Implement clear visual feedback for user actions (e.g., loading indicators, success messages, error alerts, confirmation dialogs).
*   **Accessibility:** Adhere to WCAG (Web Content Accessibility Guidelines) where possible, leveraging Clarity's built-in accessibility features to ensure the application is usable by individuals with disabilities.

## 10. Technical Requirements
*   **Frontend Technologies (Angular, TypeScript, Clarity):** The frontend will leverage Angular 16+, TypeScript, and the Clarity Design System as established by the boilerplate. RxJS will be used for reactive programming, and Angular's HttpClient for API communication. A rich text editor library (`@ckeditor/ckeditor5-angular` or similar) will be integrated for US-011.
*   **Backend Technologies (Python Flask, PostgreSQL):** The backend will be developed with Python 3.9+ using the Flask microframework to expose RESTful API endpoints. Gunicorn will serve the application. PostgreSQL will be the primary database, accessed via SQLAlchemy with Flask-SQLAlchemy.
*   **API Design:** A RESTful API will be designed with clear resource-based URLs and standard HTTP methods (GET, POST, PUT, DELETE). JSON will be the primary data exchange format. All user-specific operations will require JWT-based authentication.
*   **Authentication & Authorization:** Implement JWT for stateless authentication. Passwords will be securely hashed (e.g., bcrypt). Backend API endpoints will enforce authorization, ensuring users can only access their own data. HTTPS will secure all data in transit.
*   **Data Model:** The database will include `User`, `Note`, and `Tag` entities with appropriate relationships (`User` 1:N `Note`, `Note` M:N `Tag` via `Note_Tag` join table), as detailed in `architecture_document.md`.
*   **Input Validation & Sanitization:** Rigorous input validation will be implemented on both frontend and backend. Backend will sanitize all rich text content to prevent XSS.
*   **Containerization:** Both frontend and backend applications will be containerized using Docker, enabling consistent development and deployment environments. Docker Compose will be used for local multi-service orchestration.

## 11. Success Metrics & KPIs
*   **Registration Rate:** Percentage of visitors who complete user registration.
*   **Active User Rate (DAU/MAU):** Number of daily/monthly active users logging in and performing actions.
*   **Notes Created per User:** Average number of notes created by active users over a period.
*   **Note Retrieval Speed:** Average time taken to load the notes list and individual notes (should meet NFR-001).
*   **Search/Filter Usage:** Percentage of active users utilizing search and filter functionalities.
*   **Error Rate:** Number of backend API errors or frontend critical errors (aim for <0.1%).
*   **Security Vulnerabilities:** Number of identified and remediated critical/high-severity vulnerabilities.
*   **Uptime:** Percentage of time the application is available to users.

## 12. Risk Assessment
*   **R1: Security Vulnerabilities:** Risk of data breaches or unauthorized access due to flawed authentication/authorization or injection vulnerabilities.
    *   **Mitigation:** Implement robust security practices (bcrypt, JWT, HTTPS, input sanitization, rate limiting), regular security audits, and follow secure coding guidelines. Frontend and backend validation are critical.
*   **R2: Scope Creep:** Tendency to add more features beyond the MVP, delaying delivery.
    *   **Mitigation:** Strict adherence to the phased approach, clear MVP definition, ruthless prioritization, and continuous review of requirements against business value.
*   **R3: Performance Bottlenecks:** Slow load times or unresponsive UI, especially with large numbers of notes or concurrent users.
    *   **Mitigation:** Database indexing, optimized API queries, efficient frontend rendering (lazy loading, virtual scroll), caching (future consideration), and load testing.
*   **R4: Rich Text Editor Integration Complexity:** Challenges in integrating a third-party rich text editor, handling its data (HTML/Markdown), and ensuring security (XSS prevention).
    *   **Mitigation:** Thorough evaluation of editor libraries, careful implementation of content sanitization, and dedicated testing for formatting and security.
*   **R5: Backend-Frontend Integration Issues:** Mismatches in API contracts, authentication flows, or data serialization.
    *   **Mitigation:** Early and continuous communication between frontend and backend teams, clear API documentation (Swagger/OpenAPI), and integration testing.
*   **R6: Database Scalability:** Performance degradation with a very large number of users/notes.
    *   **Mitigation:** Proactive database tuning, appropriate indexing, and consideration of sharding or other scaling strategies for future growth.

## 13. Timeline & Milestones
**Phase 1: Minimum Viable Product (MVP) - Core Features (Estimated: 4-6 Sprints)**
*   **Sprint 1-2: Setup & Authentication Foundation**
    *   Backend: Flask API for User Registration & Login (JWT integration, password hashing, DB schema for Users).
    *   Frontend: Angular Auth Module (Register/Login components, AuthGuard, Auth Service).
    *   **Milestone:** M1.1 (Backend Auth API Complete), M1.2 (Frontend Auth UI/Integration Complete)
*   **Sprint 3-4: Core Notes CRUD**
    *   Backend: Flask API for Notes CRUD (DB schema for Notes, User-Note relationship, authorization).
    *   Frontend: Angular Notes Module (Notes List, Note Detail, Note Editor components for basic text, integration with Notes API).
    *   **Milestone:** M1.3 (Backend Notes CRUD API Complete), M1.4 (Frontend Notes CRUD UI/Integration Complete)
*   **Sprint 5-6: MVP Polish & Testing**
    *   Refine UI/UX for core features, implement feedback messages, unit/integration testing, bug fixing.
    *   **Milestone:** M1.5 (End-to-End MVP Tested & Ready)

**Phase 2: Enhanced Features (Estimated: 4-6 Sprints)**
*   **Sprint 7-8: Search & Filter Integration**
    *   Backend: Extend Notes API for keyword search, filter by tag, (DB indexing for search).
    *   Frontend: Implement search bar, filter UI (tag selection), update Notes List to reflect results.
    *   **Milestone:** M2.1 (Backend Search/Filter/Tagging API Complete - initial)
*   **Sprint 9-10: Rich Text & Tagging System**
    *   Backend: Extend Notes API for tag management (DB schema for Tags & Note_Tag join table), support rich text content storage.
    *   Frontend: Integrate Rich Text Editor (`@ckeditor/ckeditor5-angular`), implement tag input/display components in Note Editor.
    *   **Milestone:** M2.2 (Frontend Search/Filter/Tagging UI/Integration Complete)
*   **Sprint 11-12: Advanced Features Polish & Testing**
    *   Refine UI/UX for advanced features, comprehensive testing, performance optimization, bug fixing.
    *   **Milestone:** M2.3 (End-to-End Enhanced Features Tested & Ready)

## 14. Dependencies & Assumptions
*   **D1: Base Project Stability:** The Angular Clarity boilerplate provides a stable and functional frontend foundation that can be extended without significant refactoring.
*   **D2: Backend API Availability:** Backend API endpoints will be developed concurrently and available for frontend integration as per the phased timeline.
*   **D3: Third-Party Libraries:** Stability and compatibility of chosen third-party libraries (e.g., rich text editor, JWT library, ORM) for both frontend and backend.
*   **D4: Development Environment:** All developers have access to a consistent development environment (e.g., Docker).
*   **A1: Team Expertise:** The development team has sufficient expertise in Angular, Python Flask, PostgreSQL, and security best practices.
*   **A2: API Contract:** Clear API contracts (request/response schemas) will be defined and adhered to by both frontend and backend teams.
*   **A3: Security Audits:** Security audits will be performed periodically to identify and address vulnerabilities.
*   **A4: Iterative Feedback:** Agile processes will allow for continuous feedback and adaptation of requirements.

