Hi, I'm

Ahsan Khalid

Senior Engineer buildingSaaS & AI systems

I design and build production-grade software end to end — from system architecture and backend services to AI workflows, integrations, security, and scalable infrastructure.

Open to senior/lead engineering opportunities

Top Rated on Upwork100% Job Success

View proof of work

Where I've Worked

Senior Software Engineer @AutoSetter

January 2024 - Present

Led a zero-downtime architectural transformation of a production AI SaaS platform, restructuring a tightly coupled Node.js/PostgreSQL system into modular domains with clear service boundaries.
Designed organization-scoped PostgreSQL multi-tenancy and RBAC, enforcing tenant isolation consistently while allowing new organizations to be onboarded without tenant-specific code.
Re-engineered asynchronous processing with PostgreSQL, Redis, and Graphile Worker for durable job execution, idempotency, debouncing, retries, and failure recovery.
Built production Gemini-based conversation workflows with fallback strategies and internal observability tooling for tracing, diagnosing, and safely operating automated AI pipelines.

Featured

Selected Work

Production systems I've built and owned end to end — from architecture and security to deployment and operations.

01Case Study

AutoSetter

Live

Jan 2024 — Aug 2026

Node.js · TypeScript · PostgreSQL · Redis · AI/LLM · GraphQL

Production AI SaaS platform spanning multi-tenancy, workflow automation, background jobs, AI conversation orchestration, and observability.

Challenge

Evolve a production AI SaaS platform whose tightly coupled architecture made new features, asynchronous workflows, and AI automation increasingly difficult to operate safely.

Solution

Led a zero-downtime architectural refactor into modular domains with clearer service boundaries, while introducing organization-scoped PostgreSQL isolation, RBAC, durable background processing, and production observability.

Impact

Improved the platform's ability to evolve and operate reliably by separating core domains, moving critical work to durable asynchronous processing, and making automated AI workflows traceable and recoverable.

Key Outcomes

▹Led a zero-downtime architectural transformation while preserving existing production behavior
▹Designed organization-scoped PostgreSQL isolation and RBAC so new tenants could be onboarded without tenant-specific code
▹Built durable asynchronous processing with PostgreSQL, Redis, and Graphile Worker, including idempotency, debouncing, retries, and failure recovery
▹Engineered Gemini conversation workflows with fallback behavior and internal tracing tools for production debugging

02Case Study

CayPal

Live

Apr 2026 — Aug 2026

1 / 7

Next.js · TypeScript · PostgreSQL · Node.js · QuickBooks · EDI

Payment operations platform for Cayman Islands businesses, connecting accounting workflows to structured bank payments.

Challenge

Build a secure payment operations system that translates accounting workflows, banking constraints, approval controls, and financial compliance requirements into reliable software.

Solution

Designed and built the platform end to end, including the three-role authorization model, dual-approval workflows, TOTP 2FA, deterministic EDI generation, payment state management, and QuickBooks Online integration.

Impact

Turned complex banking and accounting requirements into controlled, auditable payment workflows suitable for production financial operations.

Key Outcomes

▹Designed Tenant Admin, Submitter, and Approver authorization boundaries with dual-approval controls
▹Engineered deterministic EDI generation for bank-ready payment processing
▹Integrated QuickBooks Online to connect accounting workflows with payment operations
▹Implemented TOTP 2FA, audit logging, and controlled transaction state transitions

03Case Study

K-beauty

Live

2025

Node.js · PostgreSQL · React · Stripe · RLS · RBAC

Multi-tenant wholesale operations platform with database-enforced tenant isolation and workflow-controlled financial operations.

Challenge

Build a wholesale operations system where vendors, logistics teams, staff, and administrators could operate within the same platform without compromising tenant-level data boundaries.

Solution

Designed PostgreSQL Row-Level Security and RBAC around the application's tenant model, with approval-controlled financial workflows and tenant onboarding that required no schema changes.

Impact

Established database-enforced tenant isolation and reusable onboarding patterns, allowing additional tenants to operate within the same application architecture.

Key Outcomes

▹Enforced tenant isolation at the PostgreSQL RLS layer rather than relying solely on application-level checks
▹Designed RBAC across vendor, logistics, staff, and administrator roles
▹Onboarded a second tenant without modifying the database schema
▹Built approval workflows for vendor bank-detail changes, bulk orders, invoicing, and payment tracking
▹Added timestamped audit trails for financial and operational accountability

Notable Projects

What's Next

Get In Touch

Have a product to build, a system to improve, or a complex engineering problem to solve?

I'm open to senior/lead engineering opportunities and long-term product-focused work. Let me know how I can help.

Say Hello