Engineering high-throughput platforms & resilient backend APIs.
12+ years building enterprise architectures and scalable backends. Lead platform architect behind Legiit (2M+ active users, $40M+ volume). Specialist in Laravel, Node.js, Python, PostgreSQL, Next.js, and Stripe payment systems.
Platform architecture powering Legiit.com global transactions.
Deployments across healthcare, legal, SaaS, fintech & commerce.
Over 125+ verified five-star client reviews on Freelancer & Upwork.
Full lifecycle development from scratch to multi-tenant scaling.
Scaling Legiit to 2,000,000+ Users
Served as Lead Engineer & Platform Architect. Re-engineered core transaction pipelines, search indexing, real-time messaging, and multi-currency payouts to support exponential marketplace growth.
High-Concurrency Marketplace Core
Architected the entire billing flow, wallet escrow holding, instant seller payouts, and WebSockets messaging. Scaled platform with zero service interruptions during major peak events.
10 Bottlenecks in Scalable Systems — Diagnosed & Resolved
How I identify root causes, evaluate framework trade-offs, and engineer high-concurrency solutions that keep systems fast and reliable under heavy traffic.
Database N+1 Query Cascade & Pool Starvation
Resolving 500+ independent SQL roundtrips per page load on high-volume marketplace dashboards.
ORM Lazy-Loading in Loop
Fetching seller orders triggered N separate queries for items, buyers, and ledger details, consuming all available database connection pool slots during traffic surges.
Architectural Trade-offs Evaluated
• In-Memory Node.js Joins: Created heavy RAM bloat and blocked event loop under 1,000 QPS.
• Microservice Split: Added unacceptable network hop latency to checkout path.
• Engineered Approach: Relational eager loading with column projections + composite B-Tree indexing + Redis tagged write-through cache.
Single-Pass Relational Execution
Collapsed 500 queries down to 2 optimized single-pass queries with composite index on (seller_id, status, created_at) and atomic cache invalidation.
// ✅ MASTER FIX: Relational Eager Loading + Redis Tagged Cache
public function getSellerOrders(Request $request) {
$sellerId = $request->user()->id;
$cacheKey = "seller:{$sellerId}:orders:page:" . $request->get('page', 1);
return Cache::tags(["seller_{$sellerId}_orders"])->remember($cacheKey, 120, function () use ($sellerId) {
return Order::query()
->with(['items:id,order_id,title,price_cents', 'buyer:id,name,avatar_url', 'escrowDetails:id,order_id,status'])
->where('seller_id', $sellerId)
->where('status', OrderStatus::PAID)
->orderBy('created_at', 'desc')
->paginate(25); // Exactly 2 single-pass SQL statements
});
}Different Industries. Same Standard.
Showcasing all 60+ production platforms, customer portals, and lead engines deployed for real businesses.
Legiit
Payment processing handling 1000+ transactions daily
Legiit Shop
Brand swag store with global fulfillment integration
Prescription PR
Reputation management for 100+ medical professionals
Broadway Diagnostic & Rehabilitation
Online booking system processing 200+ appointments monthly
Infusalounge
Membership subscription system with recurring billing
Ortho Spine Care LI
Patient education portal with treatment guides
Express Diagnostics
Insurance eligibility verification system
Dr Brian Capogna
High-conversion site for Top Doctor (Castle Connolly)
Dr Jay Riess
Rehabilitation service showcase
Ligament Laxity Analysis
Sales platform for 'LigMaster' diagnostic software
Movement Concepts
Multi-location PT clinic site
Skin Apeel
Award-winning spa site (Boca Raton)
Assostefano Bambini E Marfan
Italian non-profit for Marfan Syndrome
Flowers Law Group NY
Client intake automation reducing admin time by 60%
JDB Mediation
Personal branding for Justin Borer, Mediator
Long Island Loyalty
Registration system processing 500+ signups per season
Inside The Game Sports
Content management system for sports journalism
Wall Baller
Official site for Lacrosse-themed iOS Arcade Game
LaxEdits
High-energy recruiting videos for college athletes
NYFBR
League standings and stats tracking
Semper Strong
Fitness community for veterans
The Foamory
Custom WooCommerce store with subscription products
Hubert Vester Auto Group
Inventory management with 200+ vehicles
StarVox Capital
Secure client portal for investment management
Hire Regard
Talent ecosystem connecting companies with top tier candidates
Advanced Egress Solutions
Niche B2B catalog for emergency exit systems
Sprinklrite
Seasonal service scheduling automation
Evans Tree and Land Services LLC
Emergency storm response dispatch
Instant Cash Buyers
High-speed property offer generation
BeWealthy
Financial literacy course platform
Riverrode
Fleet management and logistics info
indoorclimatesolutionstn
Climate control solutions for Tennessee homes
Boats Perry Neblett
Subdomain for maritime legal resources
bellalimento
Popular food blog 'Beautiful Food Simple'
rachlmansfield
Brand partnerships and healthy recipe platform
Lotus Restaurant
Online ordering for local dining
The Zen Kat
Holistic wellness and yoga resources
simpleweddingday
Destination wedding package booking
Designing For A Difference
Charitable design project showcase
Faith Family Fulfillment Podcast
Podcast episode hosting and show notes
Align Your Nine
Enneagram coaching services
HeartCore Growth
Growth mindset coaching platform
Show Up More
Motivational speaking and coaching
Reef Tank Addict
Aquarium hobbyist resource
LA12
Local community organization site
Legiit
Payment processing handling 1000+ transactions daily
Legiit Shop
Brand swag store with global fulfillment integration
Prescription PR
Reputation management for 100+ medical professionals
Broadway Diagnostic & Rehabilitation
Online booking system processing 200+ appointments monthly
Infusalounge
Membership subscription system with recurring billing
Ortho Spine Care LI
Patient education portal with treatment guides
Express Diagnostics
Insurance eligibility verification system
Dr Brian Capogna
High-conversion site for Top Doctor (Castle Connolly)
Dr Jay Riess
Rehabilitation service showcase
Ligament Laxity Analysis
Sales platform for 'LigMaster' diagnostic software
Movement Concepts
Multi-location PT clinic site
Skin Apeel
Award-winning spa site (Boca Raton)
Assostefano Bambini E Marfan
Italian non-profit for Marfan Syndrome
Flowers Law Group NY
Client intake automation reducing admin time by 60%
JDB Mediation
Personal branding for Justin Borer, Mediator
Long Island Loyalty
Registration system processing 500+ signups per season
Inside The Game Sports
Content management system for sports journalism
Wall Baller
Official site for Lacrosse-themed iOS Arcade Game
LaxEdits
High-energy recruiting videos for college athletes
NYFBR
League standings and stats tracking
Semper Strong
Fitness community for veterans
The Foamory
Custom WooCommerce store with subscription products
Hubert Vester Auto Group
Inventory management with 200+ vehicles
StarVox Capital
Secure client portal for investment management
Hire Regard
Talent ecosystem connecting companies with top tier candidates
Advanced Egress Solutions
Niche B2B catalog for emergency exit systems
Sprinklrite
Seasonal service scheduling automation
Evans Tree and Land Services LLC
Emergency storm response dispatch
Instant Cash Buyers
High-speed property offer generation
BeWealthy
Financial literacy course platform
Riverrode
Fleet management and logistics info
indoorclimatesolutionstn
Climate control solutions for Tennessee homes
Boats Perry Neblett
Subdomain for maritime legal resources
bellalimento
Popular food blog 'Beautiful Food Simple'
rachlmansfield
Brand partnerships and healthy recipe platform
Lotus Restaurant
Online ordering for local dining
The Zen Kat
Holistic wellness and yoga resources
simpleweddingday
Destination wedding package booking
Designing For A Difference
Charitable design project showcase
Faith Family Fulfillment Podcast
Podcast episode hosting and show notes
Align Your Nine
Enneagram coaching services
HeartCore Growth
Growth mindset coaching platform
Show Up More
Motivational speaking and coaching
Reef Tank Addict
Aquarium hobbyist resource
LA12
Local community organization site
Legiit Advertising
Self-serve ad purchasing for marketplace sellers
SuperStar SEO
Local SEO campaigns ranking clients in top 3
Easy Agency Builder
White-label website builder for marketing agencies
Heart Screen
Patient portal with secure test result delivery
MJB Wellness Center
Multi-practitioner scheduling system
Dr. Sophia Argeropoulos
Local SEO success - ranking #1 for 'Port Jeff chiropractor'
Doctor Matthew Olesiak
Personal brand site for Medical Director/Entrepreneur
Dr. Dennis Long
Hyper-local lead generation site
GetYouInShape
Bootcamp registration and transformation tracking
Matthew Olesiak
Showcase for CEO of Atlas Medical Marketing
Optimize Wellness
E-commerce for wellness supplements
Wellpower Method
Membership site for health coaching
Neblett Law
Lead generation site bringing 50+ qualified leads monthly
Insurance Loss Lawyer
Targeted landing page for high-value insurance claims
Miami Maritime Law
Dominating niche SEO for 'Miami Boat Lawyer'
Steve Weatherford
Personal brand website with training program sales
Legacy Longhorns
Non-profit community team management
Baileys Dog Park
Membership verification for private dog park
Massapequa Farmingdale Mens Club
Event management for local men's club
Respect The Game
Camp and clinic registration portal
Smoky Mountain Truck Show
Ticket sales for major automotive event
Living Word
Digital and physical product sales
Pinnacle Restoration
24/7 emergency request system
CPA Enterprises
Corporate tax service portfolio
Canadian Home Style
High-end flooring and cabinetry showcase
Applied Construction
Project bid management and showcase
True Ventilation
Commercial ventilation system showcases
Gulf Gate Security
Residential and Commercial security configs
KW Wealth
Financial planning for high net worth individuals
Next Level Specialists
Corporate strategy consulting portfolio
imagemeta
Metadata extraction API service
779cash
Local 'We Buy Houses' lead capture
Main St. Stereo
Custom car audio installation showcase
Predominantly Paleo
Paleo diet resource and cookbook author site
Grazed and Enthused
Autoimmune protocol (AIP) resource
Beauty and the Boss
Beauty product reviews and tutorials
La Beautique
High-end salon booking site
So Let's Hang Out
Gluten-free living resources
Shine On Adventures
Adventure travel guides and photography
Fearfully and Wonderfully Avery
Personal family journey blog
Answers From The Stairs
Parenting and lifestyle advice column
Jim Sabellico
Personal brand for business coach
Musical Piece
Music theory and instrument guides
PuppyPack
Dog walking and pet sitting service
Legiit Advertising
Self-serve ad purchasing for marketplace sellers
SuperStar SEO
Local SEO campaigns ranking clients in top 3
Easy Agency Builder
White-label website builder for marketing agencies
Heart Screen
Patient portal with secure test result delivery
MJB Wellness Center
Multi-practitioner scheduling system
Dr. Sophia Argeropoulos
Local SEO success - ranking #1 for 'Port Jeff chiropractor'
Doctor Matthew Olesiak
Personal brand site for Medical Director/Entrepreneur
Dr. Dennis Long
Hyper-local lead generation site
GetYouInShape
Bootcamp registration and transformation tracking
Matthew Olesiak
Showcase for CEO of Atlas Medical Marketing
Optimize Wellness
E-commerce for wellness supplements
Wellpower Method
Membership site for health coaching
Neblett Law
Lead generation site bringing 50+ qualified leads monthly
Insurance Loss Lawyer
Targeted landing page for high-value insurance claims
Miami Maritime Law
Dominating niche SEO for 'Miami Boat Lawyer'
Steve Weatherford
Personal brand website with training program sales
Legacy Longhorns
Non-profit community team management
Baileys Dog Park
Membership verification for private dog park
Massapequa Farmingdale Mens Club
Event management for local men's club
Respect The Game
Camp and clinic registration portal
Smoky Mountain Truck Show
Ticket sales for major automotive event
Living Word
Digital and physical product sales
Pinnacle Restoration
24/7 emergency request system
CPA Enterprises
Corporate tax service portfolio
Canadian Home Style
High-end flooring and cabinetry showcase
Applied Construction
Project bid management and showcase
True Ventilation
Commercial ventilation system showcases
Gulf Gate Security
Residential and Commercial security configs
KW Wealth
Financial planning for high net worth individuals
Next Level Specialists
Corporate strategy consulting portfolio
imagemeta
Metadata extraction API service
779cash
Local 'We Buy Houses' lead capture
Main St. Stereo
Custom car audio installation showcase
Predominantly Paleo
Paleo diet resource and cookbook author site
Grazed and Enthused
Autoimmune protocol (AIP) resource
Beauty and the Boss
Beauty product reviews and tutorials
La Beautique
High-end salon booking site
So Let's Hang Out
Gluten-free living resources
Shine On Adventures
Adventure travel guides and photography
Fearfully and Wonderfully Avery
Personal family journey blog
Answers From The Stairs
Parenting and lifestyle advice column
Jim Sabellico
Personal brand for business coach
Musical Piece
Music theory and instrument guides
PuppyPack
Dog walking and pet sitting service
Continuous live catalog of 60+ client systems. Hover any card to pause and inspect metrics.
Systems Engineered For Longevity
Architecture decisions focused on maintainability, query speed, transaction integrity, and minimal operational overhead.
Full-Stack SaaS & Web
Next.js 15, React 19, TypeScript, Tailwind, Server Components, and responsive mobile architecture.
High-Throughput APIs
Laravel, Node.js/NestJS, Python Django, Celery background queues, and WebSockets real-time sync.
Fintech & Billing Escrow
Stripe Connect, escrow holding, automated splits, webhook handlers, and multi-currency ledgers.
Database & Infrastructure
PostgreSQL/MySQL index tuning, Redis caching, AWS EC2/S3 deployment, and HIPAA compliance.
Architectural Rigor vs. Generic Freelance Builds
Comparing critical execution standards across production deployments. Rigorous architecture directly reduces cloud bills and eliminates refactoring debt.
"Shaq actually works with us on Legiit."
Trusted by marketplace founders, agency CEOs, and high-profile entrepreneurs to engineer scalable digital systems.
"Most developers just write code; he thinks in systems. Legiit isn't a simple website; it's a complex marketplace with intricate financial logic. He engineered the architecture that allows us to scale safely. I don't need a freelancer; I need an engineering partner."
"When I land high-stakes clients like Steve Weatherford, I can't afford 'trial and error.' I bring him in because he brings an engineering discipline to agency chaos. He was the technical lead behind our biggest deployments because the code is clean, the database optimized, and the delivery flawless."
"I don't know the code, I just know that my platform needs to perform as hard as I do. The team delivered a digital HQ that handles my traffic, my content, and my sales without blinking. It feels solid, fast, and professional. That's the standard."
Direct technical leadership — no junior handoffs, no agency bloat.
When you work with me, you collaborate directly with the architect who scaled Legiit to 2,000,000+ users and shipped over 115 production systems. Every critical line of code, database schema, payment flow, and infrastructure config is engineered with precision and enterprise discipline.
Open Source & Engineering Labs
Developer tools, API utilities, and full-stack modules maintained in public.
ai-tool
Multi-purpose AI toolkit featuring automated content generation, image analysis, and text processing with GPT-4 & Anthropic APIs.
seo-generator
AI-powered SEO content generator using OpenAI API. Automatically creates meta titles, descriptions, and rank-optimized web content.
supplier-portal
E-commerce supplier management system with Next.js frontend, Shopify API integration, and real-time inventory tracking.
eticket-api
High-concurrency RESTful API for event ticketing with QR code validation, seat reservation locking, and payment webhooks.
barakah-school-suite
Islamic school management system with attendance, automated fee collection via SSLCommerz, and student performance reports.
heartcore-guardian
Real-time health monitoring dashboard for tracking patient vital signs and wellness metrics with WebSocket data feeds.
Ready to engineer your next platform?
Available for technical architecture, high-concurrency SaaS builds, MVP engineering, and payment / database performance optimization.