assadullahch.
Hire as Architect

Services

SaaS. Payments. AI. Web & Mobile.
Shipped to Production, Not Staging.

Most agencies prototype. We deliver systems that are already running in production when you hit go-live. SaaS platforms built for multi-tenant scale, payment infrastructure that clears compliance from day one, AI integrations that don't collapse when the data gets messy, and web & mobile products with architecture you won't need to rip out in 18 months. Four disciplines, zero handoff gaps.

01

SaaS Development

Multi-Tenant Platforms Built for Real Scale

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Most SaaS platforms fail at the architecture level before they fail at the product level. I build multi-tenant backends with proper tenant isolation, Stripe subscription billing that does not leak revenue, and RBAC systems that do not turn into a maintenance nightmare six months in. End-to-end, from schema design to production deployment.

Multi-tenancySubscriptionsDashboardsRole-based Access

What's Included

  • Multi-tenant backend architecture with proper schema isolation
  • Stripe subscription billing: plan tiers, trials, upgrades, dunning
  • Role-based access control across tenant, org, and user levels
  • Onboarding flows and lifecycle automation
  • Admin and user dashboards with real-time data
  • REST and GraphQL APIs with webhook infrastructure
02

Fintech & Payment Systems

Stripe Infrastructure That Handles Real Money

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Payment bugs are not like other bugs. A race condition in your webhook handler or a missing idempotency key does not just throw an error. It moves real money in the wrong direction, or does not move it at all. I build Stripe Connect onboarding, marketplace payout systems, and subscription billing infrastructure where the failure modes are handled explicitly, not optimistically.

Stripe ConnectMarketplace PayoutsBillingWebhooks

What's Included

  • Stripe Connect onboarding with KYC handoff and account status management
  • Marketplace and creator payout systems with configurable platform fees
  • Subscription lifecycle management with dunning and proration
  • Idempotent webhook infrastructure with event queuing and retry logic
  • Transaction ledger and financial reporting dashboards
  • Explicit failure handling: disputes, refunds, failed payouts
03

AI Integration & Automation

LLM Features That Ship to Production

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The difference between an AI demo and an AI feature in production is context management, cost controls, failure handling, and the ability to evaluate whether the output is actually correct. I integrate LLM APIs into existing products: RAG pipelines, streaming chat interfaces, intelligent automation workflows. Built to handle real users, not controlled test conditions.

LLM IntegrationRAG PipelinesAutomationStreaming UI

What's Included

  • LLM API integration with streaming UI and context management
  • RAG pipeline: ingestion, embedding, vector indexing, retrieval tuning
  • AI-powered automation workflows with human escalation paths
  • Prompt versioning, regression testing, and output evaluation framework
  • Cost monitoring, rate limiting, and latency observability
  • Agent systems with function calling and structured output parsing
04

Web & Mobile Development

Next.js, React Native and Performance Engineering

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A slow web app is not just a bad user experience. It is lost revenue and lost search ranking. I build Next.js web applications and React Native mobile apps optimized for Core Web Vitals, SEO, and real-world load. Rendering strategy, bundle architecture, and deployment pipeline are treated as first-class engineering concerns, not configuration to figure out at the end.

Next.jsReact NativeTypeScriptPerformance

What's Included

  • Next.js web applications with SSR, SSG, ISR, or hybrid rendering
  • Cross-platform React Native mobile apps for iOS and Android
  • Component architecture and shared design system
  • State management and API integration layer
  • Core Web Vitals optimization targeting 90+ Lighthouse scores
  • CI/CD pipeline with preview environments and automated deployment
SaaS Development

This was the first time I used Fiverr to build a dashboard and Assad Ullah exceeded my expectations. Not only did I get a robust site but the level of design went beyond cookie cutter to something that feels premium and customized!

Flex S.

Founder & CEO

Complex Systems Engineering

Assad is honest, reliable and trustworthy. I had quite a complicated bit of coding that was required and Assad made light work of it. The project was scheduled to be completed within 3 days but Assad worked all through the night to get my work complete in 1 day. An absolute pleasure to work with and highly recommended.

Nab Z.

Software Engineer

How It Works

No black boxes.
Here's exactly how an engagement runs.

Engineering projects fail in the gaps — between discovery and scoping, between scoping and delivery, between delivery and maintenance. Every engagement here runs on fixed milestones with explicit sign-offs at each stage. You know what's being built, when it ships, and what done actually means before a line of code is written.

Phase 01

Product Decomposition and Risk Mapping

Before any code exists, I map your product into its system components: tenant model, data schema, permission layers, and billing logic. The point is to find the architectural decisions that are expensive to reverse and make them correctly the first time. Scaling risks and technical constraints get documented here, not discovered in month four.

Outcome

A written system map covering tenant model, data ownership boundaries, permission layers, and billing logic. Each high-risk architectural decision is flagged and justified before the build begins.

Phase 02

Architecture and Database Design

Full system design: multi-tenant schema strategy covering schema-per-tenant versus row-level security, API contracts, RBAC structure, and third-party integration points. You get a production-grade blueprint with a clear rationale behind every decision. Not just a diagram that looks good in a slide deck.

Outcome

A production-grade architecture document: schema strategy, entity-relationship design, API surface definition, RBAC matrix, and third-party integration contracts. Every decision is documented with its tradeoffs, not just its conclusion.

Phase 03

Schema Review and API Contract Sign-Off

Before the first route gets written, the database schema and API contracts go through a dedicated review pass. This is the cheapest moment to catch a flawed foreign key relationship, a missing index, or an API shape that will make the frontend painful to build. Fixing these in a document costs an hour. Fixing them after the ORM models are wired costs a week.

Outcome

A signed-off schema and API contract that both sides have reviewed and agreed on. Frontend and backend development can start in parallel against a stable contract with no rework caused by late-stage shape changes.

Phase 04

Core Platform Build

Backend-first. Authentication, tenant isolation, billing integration, and the API layer get built and tested before the dashboard goes up. Frontend dashboards and onboarding flows are built on top of a stable, tested core. Not the other way around.

Outcome

A fully functional platform: working authentication, enforced tenant isolation, integrated Stripe billing, tested API layer, and operational dashboards. Every component is integration-tested before it is handed to the next layer.

Phase 05

QA, Load Testing, and Launch

Load testing, edge case coverage, and database query optimization before any production deployment. Infrastructure is provisioned with monitoring, alerting, and runbooks that someone other than me can follow at 2am.

Outcome

A production system with verified performance under load, documented edge case handling, a query-optimized database, active monitoring and alerting, and runbooks for the failure scenarios most likely to occur in the first 90 days.

View Full Methodology

Common Questions

Anyone who quotes you a number before reading your requirements is guessing. Simple SaaS platforms start around $10-20K. Fintech platforms with custom billing engines, multi-tenant architecture, and AI integrations are significantly more. I run an architecture phase before either of us commits to a number, because scope discovered late costs three times as much to fix.

A lean MVP takes 5-10 weeks. A full-scale platform with payments, user management, and AI integrations takes 3-5 months. Timelines slip when scope grows mid-project. That is why I invest time upfront in architecture and planning before a single line of production code is written.

Both. An MVP built on the wrong architecture becomes technical debt fast. I build MVPs with the right foundations so scaling does not require a rewrite. If you need a throwaway prototype, I am not the right hire.

Yes. I have refactored legacy systems into performant architectures, eliminated race conditions in financial workflows, and migrated codebases that were actively costing companies money in downtime and support tickets. I start with an architecture audit so we both know exactly what we are working with before touching anything.

Mostly startups and high-growth product teams. Company size is not the filter. Seriousness is. I work with teams who understand that architecture decisions made in month one still matter in month eighteen.

I implement designs and advise on UX patterns for technical interfaces. I am not a visual designer. If your project needs bespoke brand identity or motion design, you need a dedicated designer in the process. I will tell you that honestly upfront rather than after the first invoice.

Yes. LLM APIs, RAG pipelines, streaming interfaces, automation workflows. I integrate AI where it solves a real problem and the existing architecture can actually support it, not as a feature checkbox to put on a pitch deck.

React, Next.js, Node.js, Laravel, AWS, Stripe, PostgreSQL, MongoDB, Redis, Docker, and LLM APIs including OpenAI and Anthropic. I use what the project actually needs, not whatever I learned most recently.

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Not Sure Where to Start?

Most projects span
multiple disciplines.

A SaaS product needs frontend, backend, payments, and sometimes AI, all in one. Send a brief and I'll map out the right architecture for your product.

What to Expect

  • Response within 24 hours
  • Free architecture scoping call
  • Clear proposal with timeline & cost
  • No obligation to proceed
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Typically responds within 24 hours