01 Full-Stack Software Engineer — Dhaka, BD

I build the software a business runs on.

Custom business web apps — CRM, e-commerce, AI automation, and business platforms — engineered full-stack, delivered fast with AI-assisted development, grounded in fundamentals.

Open to freelance, remote roles & startup collaborations
02 About

From business problem to production system.

Full-stack engineer specialising in CRM, ERP, and SaaS platforms — using AI as an accelerator, not a replacement for engineering fundamentals.

My strongest work is turning complex business processes into practical, production-grade software systems.

I'm a full-stack software engineer focused on scalable business software — CRM, ERP, SaaS platforms, and workflow-driven applications — leveraging AI-assisted development to accelerate delivery and solve complex technical problems.

I'm fluent in JavaScript/TypeScript and Python, and comfortable across the whole stack: React, Next.js, Node, Express, FastAPI, Django, Prisma, SQLAlchemy, PostgreSQL, Firebase, Supabase, Redis, and REST APIs — from frontend interfaces to backend services, databases, auth, cloud infrastructure, deployment, and architecture.

I use AI as an engineering accelerator, not a replacement for fundamentals — combining AI coding tools, LLM APIs, and agent-assisted development with solid engineering principles to move quickly across unfamiliar codebases and new technologies without being locked to one ecosystem.

My focus is the parts where business rules and data integrity matter most: role-based access control, approval and financial workflows, auditability, controlled state transitions, and third-party integrations — with real attention to edge cases, security boundaries, and the operational realities of production.

I start from the business problem, challenge assumptions, and design systems that stay reliable and maintainable as the organisation grows. The goal isn't just software that works — it's software that solves the right problem and scales with the business.

Core focus
Full-Stack DevelopmentAI-Assisted EngineeringAI SaaSCRM & ERPSaaS ProductsBusiness AutomationSystem ArchitectureAPI IntegrationWorkflow & Permission SystemsFinancial ControlsProduct Engineering
/ 01

Product-first

Understand the business problem and the workflow before choosing the technical solution.

/ 02

Full lifecycle

Requirements, architecture, build, testing, deployment, and monitoring — not just the code.

/ 03

AI-accelerated

AI coding tools and LLM APIs layered on engineering fundamentals — fast, not fragile.

/ 04

Production-grade

Reliable, maintainable, secure, and scalable — built for the realities of running in production.

03 Selected work

Systems, not demos.

Real production platforms I've engineered, plus live builds you can open and inspect. 2024–2026.

A note on the confidential work below:my strongest systems are internal business platforms built under NDA, so they're described by capability and architecture — not by client or data. Happy to walk through the design and engineering in a call.

01

AI-Automated Operations Platform Confidential

Internal business platform · full-stack
PROBLEMA services company ran sales, HR, and accounts on manual, disconnected processes — no single operational view, and updates chased by hand.BUILTA React + Node/Express platform that unifies HR, accounts, and a fully automated sales section, with custom AI agents (OpenAI & Google Generative AI) driving agentic marketing and task automation, background job queues for async work, browser push and messaging notifications, and role-based access over a Firestore data store.RESULTManual coordination replaced by automated workflows — staff act on what the system surfaces instead of tracking it down.
ReactNode.jsExpressFirebase / FirestoreRedisBullMQOpenAICustom AI AgentsRBAC
// under NDA
🔒
Client & UI withheld under NDA — design shown on request
02

Legacy Platform Modernization In Progress

PHP → Python rebuild · re-architecture
PROBLEMAn existing PHP platform had grown hard to maintain and extend, blocking new features.BUILTRe-architecting and migrating the system onto a modern Python/Flask stack with a lean, dependency-light design — a JSON API behind a vanilla-JS single-page frontend — preserving business logic and data integrity, and understanding the existing system before changing it rather than rewriting blindly.RESULTA maintainable codebase positioned for new development, migrated without disrupting the running operation.
PythonFlaskSQLiteVanilla JS SPAJSON APIDockerLegacy Migration
// under NDA
⇄
PHP → Python migration · details on request
03

Financial & File-Handling Backend Confidential

Backend engineering · money & documents
PROBLEMSystems that touch money and documents fail quietly — rounding errors, lost files, and unclear permissions.BUILTA backend that stores money as exact decimals (NUMERIC, never floats) for correct accounting, with hashed-password sessions, database migrations, and large-file handling via S3-compatible object storage (MinIO).RESULTFinancial values that stay accurate to the cent, and reliable handling of original and deliverable files at scale.
FlaskPostgreSQLNUMERIC moneyFlask-LoginBcryptMinIO / S3GunicornTraefik
// under NDA
🔒
Handles money to the cent + large-file storage
04

E-Commerce / Catalog Platform Client Work

Online store · full-stack · Next.js / Cloudflare
PROBLEMA retail business needed a fast, modern online store built around a large, frequently-changing product catalog.BUILTA Next.js 15 / React 19 storefront in TypeScript with a type-safe PostgreSQL catalog (Drizzle ORM), JWT auth validated with Zod, S3-compatible image storage, automated catalog import scripts, and a unit + end-to-end test suite — deployed on Cloudflare Workers/Pages.RESULTA production e-commerce platform with a fully typed, maintainable codebase and catalog management that updates itself instead of by hand.
Next.js 15React 19TypeScriptDrizzle ORMPostgreSQLJWT / ZodS3Cloudflare WorkersVitest / Playwright
REPLACE_WITH_LIVE_STORE_URL
Catalog
Live
Type-safe
100%
05

JobFit Copilot Featured

AI SaaS · Full-stack web app
PROBLEMJob seekers apply blindly and can't tell how well they actually fit a role.BUILTAn AI assistant that scores a saved developer profile against any job post or link, flags matched and missing skills and red flags, suggests résumé keywords, and drafts a tailored application email — all tracked in a dashboard.RESULTTurns a vague "am I a fit?" into a clear score, a red-flag list, and a ready-to-send application.
Next.jsTypeScriptSupabase AuthGemini APITailwind CSSVercel
jobfit-copilot-sigma.vercel.app
Fit score
87%
Matched
12
Missing
3
resume keywordred flagemail draft
06

SaaS Billing Starter Live

SaaS billing system
PROBLEMSubscription billing is where SaaS apps quietly leak revenue and break.BUILTA complete Stripe billing lifecycle — checkout, webhook-synced subscription state, customer portal, dunning, scheduled cancellation, duplicate-subscription prevention, and server-side plan-based feature gating.RESULTA drop-in billing layer that prevents duplicate charges and handles failed payments on its own.
Next.jsStripe BillingPrismaNeonPostgreSQLWebhooks
saas-billing-starter-one.vercel.app
Plan
Pro
MRR
$4.9k
04 Stack

The toolkit.

Chosen for shipping production business software quickly — typed, server-rendered, and AI-ready.

LanguagesAI-assisted
  • JavaScript
  • TypeScript
  • Python
  • C
  • C++
  • Java
  • C#
  • Go
  • Rust
  • PHP
  • SQL
  • HTML
  • CSS
  • Bash
  • + any language, AI-assisted
Frontend07
  • React.js
  • Next.js
  • Next.js App Router
  • TypeScript
  • Tailwind CSS
  • SaaS Dashboard
  • Responsive UI
Backend & APIs09
  • Node.js
  • Express.js
  • FastAPI
  • Django
  • REST APIs
  • Next.js API Routes
  • Server Actions
  • Auth & RBAC
  • AI API Integration
Database & Cloud09
  • PostgreSQL
  • Neon
  • Prisma
  • SQLAlchemy
  • MongoDB
  • Redis
  • Firebase
  • Firestore
  • Supabase
SaaS & Payments06
  • Stripe Billing
  • Stripe Checkout
  • Webhooks
  • Customer Portal
  • Subscription Logic
  • Plan-Based Gating
AI & Product Engineering07
  • LLM APIs
  • Gemini API
  • Agent-Assisted Dev
  • Structured AI Output
  • Prompt Design
  • Business Automation
  • Clean Architecture
Tools & Deployment06
  • Git
  • GitHub
  • Vercel
  • Postman
  • npm
  • pnpm
05 Contact

Have something worth building?

Freelance projects, remote roles, and startup collaborations — I reply to every serious message.

info.ryanabir@gmail.com →