CORECHAIN

Blockchain-Integrated Human Resource Management System

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OVERVIEW

Abstract

CoreChain represents a Human Resource Management solution predicated upon blockchain technology. By leveraging Distributed Ledger Systems and Smart Contracts, CoreChain guarantees data immutability, verifiability, and integrity, thereby substantially mitigating manual administrative overhead and operational risks.

Designed as a comprehensive, all-encompassing ecosystem, the project integrates disparate corporate management protocols and operational workflows. This consolidation facilitates the optimization of organizational governance and enhances procedural efficiency within the enterprise.

Mobile Application

This repository constitutes the CoreChain mobile application. Engineered via a cross-platform architecture, the interface is designed to be user-centric for personnel, ensuring accessibility and facilitating seamless integration into daily operations.

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MOBILE KEY FEATURES

Work

1. Task Lifecycle Management, New Task Notification
2. Project Progress Tracking, Project Management
3. Departmental Administration

Employee Self-Service

1. Personnel Records
2. Internal Feedback System
3. Salary Advance Request
4. Work Schedule & Calendar

Communication

1. Instant Messaging System
2. Video Conferencing

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TECH STACK

Mobile Application

• Framework: React Native (Expo)
• Language: TypeScript
• Routing: Expo Router
• Architecture: Feature-based / Modular
• Platform: iOS / Android

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Web Application

• Framework: Next.js
• Language: TypeScript

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Backend Services

• Core Server: NestJS
• Communication & Notification Service: Golang
• Architecture: Modular / Microservices-oriented
• Authentication: JWT, HTTP-only Cookies

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Blockchain Layer

• Network: Ethereum Testnet
• Smart Contract Language: Solidity
• Tools:
  • Truffle
  • Ganache
• Blockchain SDK:
  • Web3.js
  • Ethers.js
• Infrastructure Provider: Chainstack

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Real-time Communication & Notification

• WebSocket
• WebRTC
• Firebase Cloud Messaging (FCM)

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Database & Caching

• PostgreSQL – Primary relational database
• MongoDB – Document-based storage
• Redis – Cache, session, queue handling

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Message Broker

• Apache Kafka – Event-driven service communication

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Deployment & Infrastructure

• AWS EC2
• AWS Application Load Balancer (ALB)
• Render

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SYSTEM FUNCTIONAL MODULES

1. Identity & Security Module

• User authentication & authorization
• Role-Based Access Control (RBAC)
• Secure session management
• Account locking & forced logout
• Password recovery & security policies

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2. Infrastructure & Core Services

• API Gateway
• Inter-service communication
• Centralized logging & configuration
• Kafka-based event streaming

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3. Human Resource Management (HRM Core)

• Employee profile management
• Organizational structure
• Employment lifecycle tracking
• Blockchain-backed record verification

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4. Task & Workflow Management

• Task assignment & tracking
• Workflow status management
• Audit logs & history

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5. Blockchain & Smart Contract Integration

• Immutable HR records
• Transparent transaction history
• On-chain verification of sensitive operations

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6. Real-time Communication & Notification

• Internal chat & messaging
• Real-time notifications
• Push notifications via FCM

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PROJECT STRUCTURE

Mobile Application (React Native / Expo)

.                                   // Project root for CoreChain Mobile (React Native + Expo)
├── GoogleService-Info.plist        // iOS Firebase config (GoogleService-Info.plist)
├── README.md                       // Project README (this file)
├── android                         // Android native project (generated by Expo / React Native)
│   ├── app
│   │   ├── build.gradle            // Android app build configuration
│   │   ├── debug.keystore          // Debug signing key
│   │   ├── google-services.json    // Android Firebase config
│   │   ├── proguard-rules.pro      // ProGuard rules for release builds
│   │   └── src
│   │       ├── debug               // debug source set
│   │       ├── debugOptimized      // optimized debug build sources
│   │       └── main                // main Android source set
│   ├── build.gradle                // Top-level Gradle build file
│   ├── gradle
│   │   └── wrapper
│   │       ├── gradle-wrapper.jar
│   │       └── gradle-wrapper.properties
│   ├── gradle.properties
│   ├── gradlew                     // Gradle wrapper (Unix)
│   ├── gradlew.bat                 // Gradle wrapper (Windows)
│   └── settings.gradle
├── app                             // App routes / screens (expo-router layout)
│   ├── (auth)                      // Auth flow group (sign in / welcome)
│   │   ├── signin.tsx              // Sign-in screen
│   │   └── welcome.tsx             // Welcome/onboarding entry
│   ├── (tabs)                      // Tabbed navigation group
│   │   ├── _layout.tsx             // Tab layout wrapper
│   │   ├── calendar.tsx
│   │   ├── challange.tsx
│   │   ├── department.tsx
│   │   ├── expense.tsx
│   │   └── index.tsx               // Tab landing
│   ├── +not-found.tsx              // 404 / Not found route
│   ├── _layout.tsx                 // App-level layout wrapper
│   ├── changepassword.tsx
│   ├── chat
│   │   └── [id].tsx                // Chat detail (dynamic route by id)
│   ├── create-task.tsx
│   ├── department
│   │   └── index.tsx               // Department listing / detail
│   ├── feedback
│   │   └── index.tsx               // Feedback flow
│   ├── meeting.tsx
│   ├── messages.tsx
│   ├── notifications.tsx
│   ├── personal.tsx
│   ├── personnel
│   │   └── index.tsx               // Personnel list
│   ├── profile.tsx
│   ├── project
│   │   └── index.tsx               // Project list
│   ├── project-details
│   │   └── [id].tsx                // Project detail (dynamic)
│   ├── search-user.tsx
│   ├── task-details
│   │   └── [id].tsx                // Task detail (dynamic)
│   ├── update-profile.tsx
│   ├── versioning.tsx
│   └── video-meeting.tsx           // WebRTC / video meeting screen
├── app.json                        // Expo app config
├── assets
│   └── images
│       ├── android-icon-background.png
│       ├── android-icon-foreground.png
│       ├── android-icon-monochrome.png
│       ├── banner-wellcome.png
│       ├── favicon.png
│       ├── icon.png                // Primary app icon (used by README; update if changed)
│       ├── onboarding-1.png
│       ├── onboarding-2.png
│       ├── onboarding-3.png
│       ├── onboarding-4.png
│       ├── partial-react-logo.png
│       ├── react-logo.png
│       ├── react-logo@2x.png
│       ├── react-logo@3x.png
│       └── splash-icon.png         // Splash screen icon
├── babel.config.js                 // Babel config (JS/TS transpilation)
├── commitlint.config.mjs
├── components                      // Reusable UI components and component groups
│   ├── BottomSheet.tsx             // Generic bottom sheet wrapper
│   ├── BottomSheetModal.tsx
│   ├── InAppNotification.tsx
│   ├── Toast.tsx
│   ├── customs                     // Custom form controls and small components
│   │   ├── Checkbox.tsx
│   │   ├── CustomAlert.tsx
│   │   ├── Input.tsx
│   │   └── LoadingOverlay.tsx
│   ├── external-link.tsx
│   ├── haptic-tab.tsx
│   ├── hello-wave.tsx
│   ├── parallax-scroll-view.tsx
│   ├── screens                     // Feature screen components grouped by feature
│   │   ├── calendar
│   │   │   └── index.tsx
│   │   ├── calendar-working
│   │   │   └── index.tsx
│   │   ├── challange
│   │   │   ├── FilterModal.tsx
│   │   │   ├── ProjectItem.tsx
│   │   │   ├── TaskItem.tsx
│   │   │   ├── TaskItemSkeleton.tsx
│   │   │   └── index.tsx
│   │   ├── changepassword
│   │   │   └── index.tsx
│   │   ├── department
│   │   │   ├── UserDetailModal.tsx
│   │   │   └── index.tsx
│   │   ├── expense
│   │   │   ├── CreateRequestModal.tsx
│   │   │   ├── RequestListSkeleton.tsx
│   │   │   └── index.tsx
│   │   ├── feedback
│   │   │   ├── CreateFeedbackModal.tsx
│   │   │   ├── FeedbackSkeleton.tsx
│   │   │   └── index.tsx
│   │   ├── home
│   │   │   └── index.tsx
│   │   ├── leave
│   │   │   └── index.tsx
│   │   ├── meeting
│   │   │   ├── CreateMeetingModal.tsx
│   │   │   └── index.tsx
│   │   ├── messages
│   │   │   ├── ChatDetail.tsx
│   │   │   ├── EmptyState.tsx
│   │   │   ├── SearchUser.tsx
│   │   │   ├── UserItemSkeleton.tsx
│   │   │   └── index.tsx
│   │   ├── notifications
│   │   │   └── index.tsx
│   │   ├── personal
│   │   │   └── index.tsx
│   │   ├── profile
│   │   │   └── index.tsx
│   │   ├── signin
│   │   │   ├── SignInModal.tsx
│   │   │   └── index.tsx
│   │   ├── task-details
│   │   │   └── index.tsx
│   │   ├── update-profile
│   │   │   └── index.tsx
│   │   ├── versioning
│   │   │   └── index.tsx
│   │   ├── video-meeting
│   │   │   └── index.tsx
│   │   └── welcome
│   │       └── Onboarding.tsx
│   ├── skeletons                    // Loading skeleton components
│   │   ├── DepartmentSkeleton.tsx
│   │   └── ProjectSkeleton.tsx
│   ├── themed-text.tsx
│   ├── themed-view.tsx
│   └── ui
│       ├── collapsible.tsx
│       ├── icon-symbol.ios.tsx     // iOS-specific icon component
│       └── icon-symbol.tsx
├── configs
│   ├── api.ts                       // API endpoints and client config
│   └── route.ts                     // Route definitions used by app
├── constants
│   └── theme.ts                     // Theme constants (colors, spacing)
├── context
│   └── SocketContext.tsx            // WebSocket context provider
├── eas.json                         // Expo Application Services config (builds)
├── eslint.config.js
├── expo-env.d.ts                    // Expo TypeScript environment definitions
├── global.css                       // Shared global styles for web (if used)
├── google-services.json             // Firebase config for Android
├── helpers
│   └── api.ts                       // Thin API helper wrapper
├── hooks                            // Custom React hooks for app logic
│   ├── mutations
│   │   └── index.ts
│   ├── queries
│   │   └── index.ts
│   ├── use-color-scheme.ts
│   ├── use-color-scheme.web.ts
│   ├── use-theme-color.ts
│   ├── useAppState.ts
│   ├── useDebounce.tsx
│   ├── useKeyboard.ts
│   ├── useOnlineManager.ts
│   └── useSocket.ts
├── libs
│   ├── cn.ts                        // classNames helper
│   └── firebase.ts                  // Firebase initialization & helpers
├── metro.config.js                  // Metro bundler config (React Native)
├── mocks                            // Mock data used in development / storybooks
│   ├── departments.ts
│   ├── project.ts
│   ├── salary-request.ts
│   └── task.ts
├── nativewind-env.d.ts
├── package-lock.json
├── package.json                     // npm/Yarn package manifest
├── queue
│   └── task-queue.ts                // Simple in-app task queue utility
├── scripts
│   └── reset-project.js             // Dev helper script to reset local state
├── services                         // Business-layer services (API clients & domain logic)
│   ├── auth.service.ts
│   ├── conversation.service.ts
│   ├── department.service.ts
│   ├── feedback.service.ts
│   ├── file.service.ts
│   ├── firebase.service.ts
│   ├── meeting.service.ts
│   ├── notification.service.ts
│   ├── personnel.service.ts
│   ├── position.service.ts
│   ├── project.service.ts
│   ├── task.service.ts
│   └── user.service.ts
├── stores
│   └── auth-store.ts                // Simple local state store for authentication
├── structure.txt                    // Original tree output (raw)
├── tailwind.config.js               // Tailwind config (if using web)
├── tsconfig.json                    // TypeScript config
├── types                            // Shared TypeScript types/interfaces
│   ├── api.ts
│   ├── common.ts
│   ├── department.ts
│   ├── feedback.ts
│   ├── personnel.ts
│   ├── position.ts
│   ├── project.ts
│   ├── report.ts
│   ├── task.ts
│   └── user.ts
└── utils
    └── axios.ts                     // Preconfigured Axios instance

61 directories, 173 files               // Total (as reported by tree)

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