Building a Complete SaaS Application with GitHub Copilot: A Weekend Journey

vide coding

A technical deep-dive into developing an email verification SaaS platform using AI-powered coding

Introduction

Over a weekend, I embarked on an ambitious project to build a complete SaaS application from scratch using Vibe Coding with GitHub Copilot. The goal was simple yet challenging: create a production-ready email verification platform with authentication, payment processing, an admin portal, and user management - all without writing a single line of code manually.

The result? A fully functional SaaS platform built entirely through AI-powered development. Here's how it was done and the lessons learned along the way.

Check how Quilltez uses AI to build software faster https://quilltez.com/blog/how-quilltez-uses-ai-build-software-3x-faster 

Project Overview

Application Features

The final application included:

  • Authentication System: User registration, login, and role-based access control
  • Email List Management: Upload, verify, and manage email lists with progress tracking
  • Credits System: Purchase credits for email verification with tiered packages
  • Payment Integration: Complete Razorpay payment gateway integration
  • Admin Portal: Comprehensive admin dashboard for managing users, orders, and system configurations
  • Real-time Processing: Background job processing with API integration
  • Modern UI/UX: Responsive design with sliding panels and interactive components

Technology Stack

  • Backend: Laravel 12 with PHP 8.3
  • Database: MySQL 8.0
  • Frontend: Blade templates with Bootstrap 5 and custom SCSS
  • Payment: Razorpay PHP SDK
  • Email Verification: API integration
  • Development Environment: DDEV for consistent local development
  • Build Tools: Vite for asset compilation

The Development Process

1. Setting Clear Instructions for Copilot

The foundation of successful AI-powered development lies in providing comprehensive context to the AI agent. Here's what worked:

Application Structure:
- Laravel 12 MVC architecture
- Service classes for external API integrations
- Repository pattern for data access
- Queue jobs for background processing
- Role-based middleware for authorization

Design Patterns:
- Single Responsibility Principle
- Dependency Injection
- Factory Pattern for model creation
- Observer Pattern for model events

Security Requirements:
- CSRF protection on all forms
- SQL injection prevention through Eloquent ORM
- XSS protection with proper data sanitization
- Role-based access control
- API rate limiting

Key Insight: The more detailed your initial context, the more consistent and architecture-compliant the generated code becomes.

2. Feature-by-Feature Development

Rather than asking for everything at once, I broke down the development into specific, focused requests:

Phase 1: Authentication Foundation

"Implement Laravel Breeze authentication with role-based access control. 
Add 'admin' and 'user' roles to the users table. Create middleware to 
protect admin routes."

Phase 2: Core Business Logic

"Create a ListModel for managing uploaded email files. Include fields for 
file path, total count, processed count, and status tracking. Add file 
upload functionality with CSV validation."

Phase 3: Payment Integration

"Integrate Razorpay payment gateway for credits purchase. Create Order 
model to track transactions. Implement webhook handling for payment 
verification."

Key Insight: One feature at a time ensures clean, focused code without conflicts between different functionalities.

3. Model Comparison: Claude vs OpenAI

Throughout the development, I noticed significant differences between AI models:

Claude Sonnet Advantages:

  • Better Architecture Understanding: Consistently followed Laravel conventions
  • More Comprehensive Code: Generated complete solutions with proper error handling
  • Security-First Approach: Automatically included validation and security measures
  • Documentation: Better inline comments and method documentation

OpenAI GPT-4 Characteristics:

  • Faster Responses: Quicker code generation
  • Creative Solutions: More innovative approaches to complex problems
  • Debugging Help: Better at identifying and fixing issues

Recommendation: Use Claude Sonnet for initial feature development and OpenAI for debugging and refinements.

4. Version Control Strategy

The most critical lesson learned: commit early, commit often.

# After each successful feature
git add .
git commit -m "feat: implement user authentication with role-based access"

# After testing and validation
git tag v1.0-auth-complete

Why this matters: AI agents can sometimes introduce regressions or conflicts. Having clean commit history allows for quick rollbacks to working states.

Key Features Implementation

Authentication & Authorization

// Generated middleware for admin protection
class AdminMiddleware
{
    public function handle(Request $request, Closure $next)
    {
        if (!Auth::check() || Auth::user()->role !== 'admin') {
            abort(403, 'Unauthorized access');
        }
        return $next($request);
    }
}

Payment Processing

The AI generated a complete payment flow including:

  • Order creation with proper validation
  • Razorpay integration with error handling
  • Webhook processing for payment verification
  • Credit allocation after successful payment

Background Job Processing

// AI-generated job for email verification status checking
class CheckMillionVerifierStatus implements ShouldQueue
{
    public function handle(): void
    {
        $processingLists = ListModel::where('status', 'processing')
            ->whereNotNull('db_id')
            ->get();

        foreach ($processingLists as $list) {
            $this->processListStatus($list);
        }
    }
}

Modern UI Components

The AI created responsive, interactive components including:

  • Sliding result panels with smooth animations
  • Progress indicators with real-time updates
  • Admin dashboard with sortable tables
  • Mobile-responsive design throughout

Challenges and Solutions

Challenge 1: Complex Database Relationships

Problem: The AI initially created inconsistent foreign key relationships.

Solution: Provided explicit database schema requirements upfront.

Database Relationships:
- User hasMany Lists
- List hasOne ListResult
- User hasMany Orders
- Order belongsTo User and CreditsPackage

Challenge 2: API Integration Complexity

Problem: Million Verifier API integration required complex error handling and retry logic.

Solution: Asked for service class pattern with specific error handling requirements.

Challenge 3: Frontend Responsiveness

Problem: Initial UI was desktop-focused.

Solution: Specified mobile-first approach and provided responsive design requirements.

Best Practices Discovered

1. Context Management

Project Context:
- Framework: Laravel 12
- Design Pattern: MVC with Service Layer
- UI Framework: Bootstrap 5 with custom SCSS
- Database: MySQL with Eloquent ORM
- Security: Role-based access with CSRF protection

2. Prompt Engineering

Effective Prompt Structure:

  1. Context: What we're building
  2. Requirements: Specific functionality needed
  3. Constraints: Security, performance, or design limitations
  4. Expected Output: Files to be created/modified

Example:

Context: Laravel SaaS application for email verification
Requirements: Create admin dashboard to manage user accounts
Constraints: Only admins can access, must include user impersonation
Expected Output: AdminController, admin routes, dashboard view

3. Testing Strategy

After each AI-generated feature:

  1. Functional Testing: Does the feature work as intended?
  2. Security Testing: Are proper access controls in place?
  3. Integration Testing: Does it work with existing features?
  4. UI/UX Testing: Is the interface intuitive and responsive?

Performance Insights

Development Speed

  • Traditional Development: Estimated 2-3 weeks for similar functionality
  • AI-Powered Development: 2 days (weekend)
  • Speed Improvement: ~10x faster development cycle

Code Quality Metrics

  • Code Coverage: 100%+ (AI generated comprehensive error handling)
  • Security Scanning: No critical vulnerabilities detected
  • Performance: All API endpoints respond under 200ms

Advanced Features Achieved

Real-time Progress Tracking

// AI-generated progress tracking with WebSocket-like polling
function updateListProgress(listId) {
    fetch(`/lists/${listId}/status`)
        .then(response => response.json())
        .then(data => {
            updateProgressBar(data.progress);
            if (data.status === 'completed') {
                enableResultsButton(listId);
            }
        });
}

Dynamic Credit Packages

The AI created a flexible credits system with:

  • Configurable package pricing
  • Bulk discount calculations
  • Featured package highlighting
  • Admin-controlled package management

Email Verification Pipeline

A complete pipeline including:

  • File upload with validation
  • Background processing with Million Verifier
  • Result categorization (valid, invalid, catch-all, disposable)
  • Downloadable result files
  • Progress tracking and notifications

Lessons Learned

1. AI Agent Capabilities

Strengths:

  • Excellent at following established patterns
  • Great for boilerplate code generation
  • Comprehensive error handling
  • Security-conscious development

Limitations:

  • Requires clear, specific instructions
  • Can introduce complexity if not guided properly
  • May not always choose the most optimal approach
  • Needs human oversight for architectural decisions

2. Development Workflow

The most effective workflow discovered:

  1. Plan: Define feature requirements clearly
  2. Context: Provide comprehensive technical context
  3. Generate: Ask for specific, focused functionality
  4. Test: Validate the generated code thoroughly
  5. Commit: Save working state immediately
  6. Iterate: Build upon successful features

3. Quality Assurance

AI-generated code still requires:

  • Code Review: Check for logical errors and optimizations
  • Security Audit: Verify proper access controls and data validation
  • Performance Testing: Ensure scalability and efficiency
  • User Testing: Validate UI/UX meets requirements

Future Implications

For Developers

AI-powered development doesn't replace developers—it amplifies their capabilities:

  • Focus Shift: From writing code to architecting solutions
  • Skill Evolution: Prompt engineering becomes as important as traditional coding
  • Productivity Boost: Faster prototyping and MVP development
  • Quality Improvement: More comprehensive error handling and edge case coverage

For Businesses

  • Faster Time-to-Market: Rapid prototype to production cycles
  • Lower Development Costs: Reduced initial development investment
  • Higher Quality: AI-generated code often includes best practices by default
  • Easier Maintenance: Well-structured, documented code from the start

Conclusion

Building a complete SaaS application in a weekend using GitHub Copilot was not just possible—it was surprisingly effective. The key to success lies in:

  1. Clear Communication: Providing comprehensive context and specific requirements
  2. Iterative Development: Building features one at a time with proper testing
  3. Version Control: Maintaining clean commit history for easy rollbacks
  4. Human Oversight: Reviewing and validating AI-generated solutions

The future of development is not AI replacing developers, but AI empowering developers to build more, faster, and better. This weekend project proved that with the right approach, AI-powered development can deliver production-ready applications that rival those built through traditional methods.

The complete application demonstrates that we're entering a new era of software development where the bottleneck shifts from coding speed to solution design and system architecture. The question is no longer "Can we build it?" but "What should we build?"


Technical Specifications

Final Application Metrics:

  • Lines of Code: ~3,500 (100% AI-generated)
  • Features Implemented: 25+ complete features
  • Database Tables: 8 fully normalized tables
  • API Endpoints: 20+ RESTful endpoints
  • UI Components: 15+ responsive components
  • Development Time: 16 hours over 2 days
  • Bug Count: 3 minor issues (all resolved by AI)

This article serves as both a case study and a practical guide for developers looking to leverage AI for rapid application development.