I build production systems that don’t break under real load.

Multi-tenant SaaS, omnichannel e-commerce & POS platforms, high-throughput Laravel APIs, automated courier & payment pipelines, and database layers that stay fast when traffic arrives.

Engineering production systems for French enterprise teams, UK hospitality platforms, and high-volume commerce brands since 2022 — available for full-time remote roles, dedicated team collaboration, and client projects.

View selected work Get in touch Download CV
4+
Years experience
10+
Production systems
3+
Countries served
Kamruzzaman Polash — Laravel & SaaS Backend Engineer

01 — Selected work

Systems in production.

Real architectures with measurable outcomes, built to survive commercial load rather than to demo well.

Flagship SaaS

Vendzoo — Omnichannel Retail & Commerce Engine

Architect & Developer · Own product
vendzoo.com ↗

An all-in-one business management SaaS for multi-branch retailers, merchants and online brands. Unifies physical POS registers, Shopify and WooCommerce inventory, and multi-courier dispatch into a single automated operational platform.

✓Order and stock sync: Webhook-driven order import from Shopify and WooCommerce with stock deduction, stock restore on cancellation, and on-demand catalog stock sync.
✓Automated logistics: One-click consignment dispatch across Pathao, Steadfast, RedX and CarryBee.
✓Fraud scoring: Heuristic cash-on-delivery risk score from order history, courier delivery history and phone consistency.
✓Built-in accounting: Double-entry ledger with Telegram order alerts and daily sales summaries.
LaravelPHPMulti-tenant SaaSShopify & WooCommerceCourier APIsCOD fraud scoring
Enterprise Platform

Payslip Platform — Annon IT

Enterprise client · France08/2024 – 09/2025

European-standard payslip generation platform integrating French statutory tax APIs with automated enterprise tenant lifecycle and SSO workspace provisioning.

✓Statutory compliance: Seamless integration with Pappers API & Mon Entreprise REST APIs.
✓−59% Provisioning time: Automated tenant onboarding, cutting manual engineering setup.
✓Containerized architecture: Robust Docker & Kubernetes cluster deployment with audit-proof PDF outputs.
✓Reduced overhead: 2 costly external vendor dependencies eliminated.
LaravelDockerKubernetesPappers APIMulti-tenancy SSOVue.js
−59%Provisioning time
2Vendors removed
Retail SaaS

SellsBook — SaaS POS & WooCommerce Sync

Multi-tenant retail POS10/2025 – 05/2026

Multi-tenant POS and inventory system with real-time WooCommerce webhooks, fraud detection alerts, and integrated local payment gateways.

✓Zero inventory drift: Bidirectional webhook engine prevents overselling between in-store and online channels.
✓Local payment integrations: Production bKash and SSLCommerz automated payment reconciliation.
✓Courier automation: Automated consignment generation and real-time delivery status polling.
✓Financial clarity: Live P&L ledger reporting for daily store audits.
LaravelWooCommerce webhooksbKash & SSLCommerzMySQL
Industrial Logistics

FlameFlow — LPG Cylinder Inventory + POS

Industrial cylinder logistics & POS04/2025 – 07/2025

Specialized cylinder tracking, security-deposit accounting, and driver route delivery manifests for an industrial LPG distribution network.

✓Zero cylinder loss: Serialized batch tracking of full vs empty cylinders throughout distribution.
✓Deposit accounting: Strict accounting ledger managing customer security deposits on cylinder shells.
✓Route manifests: Driver dispatch routes and automated trip reconciliation in FilamentPHP.
✓Automated auditing: Daily warehouse reconciliations with zero discrepancy reports.
LaravelFilamentPHPCylinder lifecycle engineMySQL
Commerce Engine

DropShop — Variant Inventory & Live Tracking

E-commerce & delivery tracking06/2025 – 08/2025

High-throughput variant-based e-commerce platform integrated directly with Pathao courier APIs for hands-free fulfillment.

✓Hands-free dispatch: Instant consignment booking upon checkout via Pathao API.
✓Live customer tracking: Real-time parcel status webhooks keeping customers informed.
✓Complex variant matrix: Multi-attribute SKU stock tracking without database slowdowns.
✓Operations speed: Eliminated manual data entry for warehouse logistics staff.
LaravelPathao APIInventory managementMySQL
Open Source

pola5h/laravel-flags

Open-source package · Packagist09/2024
GitHub ↗

An open-source Laravel package providing 249 country flags and 210 language flags through clean Blade components.

✓249 Country Flags: High-quality SVG assets rendered as zero-dependency Blade components.
✓210 Language Flags: ISO-compliant language identifiers for multilingual applications.
✓Composer installation: Published on Packagist with automated asset publishing and caching.
LaravelBlade componentsComposerOpen source

02 — About

I care about the parts of software nobody demos.

I'm Kamruzzaman Polash, a backend software engineer specialising in Laravel, PHP, and custom WordPress/WooCommerce plugin development. I build the systems that hold a product together: billing engines, inventory ledgers, background queues, and the integrations that make separate tools behave like one platform.

My work focuses on resilient third-party integration pipelines, event-driven data synchronisation, high-throughput background queues, practical LLM workflows, and database tuning under heavy write traffic. I like problems with a measurable before and after.

Currently open to full-time remote engineering positions, long-term team collaboration, and architecture contracts worldwide.

github.com/pola5h
View profile ↗
Kamruzzaman Polash GitHub contribution graph — 2026 coding activity
pola5h / laravel-flags PHP

249 country flags & 210 language flags as zero-dependency Blade components — published on Packagist.

03 — Capabilities

The toolbox, proven under load.

Technologies I reach for in production across high-traffic SaaS and retail applications.

Backend & frameworks

High-throughput REST APIs, versioned endpoints, clean MVCS architecture.

LaravelPHPREST APIsMVCSDesign patternsWordPress plugins

Commerce & logistics APIs

Two-way webhook sync, automated courier dispatches, and payment APIs.

Shopify APIWooCommerceWebhook ingestionCourier dispatchesIdempotent queuesPayment gateways

Automation & AI

Bots, marketing automation and LLM-powered background pipelines.

OpenRouter AITelegram Bot APIWhatsApp Cloud APIFacebook Marketing APIAsync workers

Database & performance

Eliminating N+1 queries, indexing execution plans, low-latency caching.

MySQL tuningComposite indexesRedis cachingN+1 auditsQuery profiling

DevOps & containerisation

Reproducible builds, cluster deployments and production Linux.

DockerKubernetesLinux serversGit workflowsPostman testing

Dashboards & TALL stack

Admin panels, reactive data tables and rapid internal tools.

FilamentPHPLivewireTALL stackVue.jsTailwind CSS

04 — Experience

Shipping in production since 2022.

Remote product teams, European enterprise clients and commerce platforms.

10/2025 – Present
Part-time · Remote
● Current
Backend EngineerNexCore IT
  • Architected and delivered an end-to-end venue & entertainment booking platform for a UK hospitality business, engineering real-time slot reservations, event ticketing, and conflict-free concurrent scheduling.
  • Engineered core backend infrastructure for an EdTech/LMS platform, featuring dynamic slot booking, live session integrations, automated recurring billing, and event-driven WhatsApp reminders.
  • Delivered backend architecture for 7+ production e-commerce and retail SaaS platforms — building POS billing engines, real-time inventory ledgers, payment gateways, automated courier dispatch, and custom WooCommerce–Laravel sync plugins.
  • Engineered enterprise integration pipelines with Facebook Marketing API and WhatsApp Business Cloud API — implementing multi-account token rotation, encrypted credential vaults, real-time ROAS analytics, and segmented broadcast queues.
08/2024 – 09/2025
Full-time · Remote
Junior Software EngineerAnnon IT
  • Built European statutory-compliance payslip generation for enterprise clients in France.
  • Integrated French government administrative endpoints (Pappers API and Mon Entreprise REST API).
  • Engineered multi-tenancy and SSO workspace provisioning, cutting onboarding time by 59% and removing 2 external dependencies.
  • Managed Docker and Kubernetes deployment manifests for production stability, and integrated OpenRouter-powered AI features.
10/2023 – 07/2024
Full-time · Remote
Laravel DeveloperLomeyo LLC
  • Delivered major features across commercial TALL-stack applications (Adlisting, JobPilot, JobFlix).
  • Maintained unit and feature test suites with PHPUnit for reliable staging deployments.
  • Integrated recurring payment gateways for subscription billing workflows.
01/2023 – 05/2023
Onsite · Dhaka, Bangladesh
Web Application DeveloperThe Riser IT
  • Built an Asset Inventory System with Laravel and normalized relational database design.
  • Executed QA on school management software, logging and resolving 30+ defects.
  • Delivered client web portals with fast load times and clean on-page SEO.
Academic Education 2018 – 2022

B.Sc. in Computer Science and Engineering

International University of Business Agriculture and Technology (IUBAT)

Thesis: Machine Learning Approaches for PE Header Based Multinomial Malware Classification

Verified Skill Software Engineer
HackerRank verified · ID f9a5e1282fde
↗
Verified Skill SQL (Advanced)
HackerRank verified · ID 835eaf3e625c
↗

05 — Recommendations

What engineering peers say.

Verifiable feedback from tech leads, developers, and teammates I ship production systems with.

Md Shubiour Shuvo

Md Shubiour Shuvo

Software Engineer

Worked with K. on the same team

“I had the pleasure of working with Kamruzzaman Polash on multiple projects, and their expertise in the TALL stack (Tailwind CSS, Alpine.js, Laravel, Livewire) and Vue.js is impressive. They consistently deliver high-quality solutions and are always eager to collaborate and help others. Kamruzzaman Polash is a valuable asset to any team, and I highly recommend them for any full-stack development role.”
Md. Nuhash Alam

Md. Nuhash Alam

Operations Engineer

Worked with K. on the same team

“Kamruzzaman is a self-starter who is a hard-working and passionate team member. He is very sincere in his work. Whenever he faces any difficulties or issues, he continuously tries to solve them until it's done. His communication and task-orientation abilities have a good effect on his work.”
Md Hasibul Hasan

Md Hasibul Hasan

Technical Lead

M.Sc. Computational Science · Studied together

“Md. Kamruzzaman is a very hard working person. I along with him have done many micro projects. He is a very efficient system designer. His main key skills are problem solving ability and thinking capability. He is a python and linux expert as well.”
Fazle Rabbi Zidan

Fazle Rabbi Zidan

Laravel Web Developer

Worked with K. on the same team

“Best team member. He is a team player and dedicated programmer.”
Ariful Islam Arif

Ariful Islam Arif

Software Engineer

Worked with K. on the same team

“I worked with Polash, who is a hardworking and enthusiastic Laravel developer. Polash is good at solving problems and always wants to learn more. He work really hard to make sure their work is really good, and he would be a great addition to any development team.”
S. M. Jamil Sagar

S. M. Jamil Sagar

Junior Officer · Eastern Bank PLC

Studied together at IUBAT

“Md. Kamruzzaman is a good person as human being, as a developer. He can solve any types of programming problems very quickly. He is quick learner. He can adopt new features and technology in a short time.”

06 — Engineering writing

Notes from production.

Deep dives and architectural patterns written from commercial systems I actually shipped.

Laravel Queue Workers in Docker: Why They Die & How to Fix It

Stop Laravel queue workers crashing in Docker: Supervisor config, --max-time, --max-jobs, memory leaks, OOM kills, and Horizon vs queue:work.

September 2026·15 min read
Laravel AI SDK + OpenRouter: A Complete Guide

Build production AI features in Laravel 13 with first-party AI SDK and OpenRouter: agents, streaming, queuing and tests.

April 2026·14 min read
Why Your Laravel Queue Workers Die (and the Fix)

Debugging memory leaks, supervisor timeouts, job retries and Redis connection drops in high-throughput environments.

March 2026·12 min read
MySQL Query Optimisation in Laravel: Stop Full Table Scans

Composite index strategies, EXPLAIN plan analysis and eliminating slow queries on multi-million row production databases.

February 2026·12 min read
Laravel REST API: Auth, Versioning & Best Practices Guide

Clean architecture for enterprise REST APIs: Sanctum authentication, request validation, API resources and rate limiting.

January 2026·15 min read
Deploy Laravel with Docker & Kubernetes: Zero Downtime

Multi-stage Docker builds, PHP-FPM / Nginx optimization, ConfigMaps and rolling cluster updates without downtime.

December 2025·10 min read
Read all 17 articles →

07 — Work with me

Services & collaboration.

Direct access to the engineer who builds it — no agency, no middlemen. You get clear milestones, fast delivery, and code you actually own.

SaaS & Core Architecture Most popular

Multi-tenant backend platforms built to scale without 3 AM outages.

Clean domain-driven backends for high-growth SaaS. Tenant data isolation, subscription billing, and versioned APIs designed so your team ships features without accumulating technical debt.

  • ✓Isolated Multi-Tenant Engine: Schema/DB-level tenant data isolation, workspace routing, and Spatie RBAC.
  • ✓Domain-Driven REST APIs: Clean MVCS patterns, OpenAPI documentation, and strict request validation.
  • ✓Automated Testing & CI: Comprehensive Pest & PHPUnit automated test suites covering critical paths.
  • ✓Subscription & Invoicing: Webhook-driven Stripe & Paddle billing lifecycles with zero duplicate events.
Discuss your platform See case studies
Commerce & Integrations

End-to-end transaction automation — checkout, logistics, and messaging.

Two-way synchronization across stores, payment gateways, couriers, and communication channels. I wire event-driven pipelines so your orders flow hands-free from cart to delivery.

  • ✓Bi-Directional Inventory Sync: Two-way real-time stock & order sync between WooCommerce, Shopify, and POS.
  • ✓Automated Courier Dispatch: Instant parcel booking via Pathao/Steadfast APIs with live webhook status tracking.
  • ✓Multi-Gateway Payments: Secure checkout integration (Stripe, SSLCommerz, bKash) with automated refunds.
  • ✓Customer Messaging Pipelines: Automated WhatsApp Cloud API alerts (order updates, OTPs) and Facebook CAPI.
Discuss your integration View commerce projects
Performance, Cloud & AI

Eliminate production bottlenecks, stabilize infrastructure, and ship AI.

I audit database queries, eliminate memory leaks, containerize for zero-downtime releases, and embed practical LLM pipelines as reliable background workers rather than brittle scripts.

  • ✓Database Profiling & Indexing: MySQL EXPLAIN audits, index tuning, and N+1 query elimination for sub-100ms APIs.
  • ✓High-Throughput Queues: Redis Horizon worker architecture with automated retry strategies and failure alerts.
  • ✓Containerized Deployments: Production Docker, Docker Compose, and automated GitHub Actions zero-downtime CI/CD.
  • ✓Queued LLM Pipelines: Reliable AI workers (OpenRouter, Gemini, OpenAI) with cost-saving response caching.
Book performance audit View technical audits

08 — FAQ

Common questions.

What kind of work do you take on?+

Backend engineering with Laravel, PHP, MySQL, Docker and Kubernetes — whether that is a greenfield API, a complex SaaS feature, AI integration (OpenRouter, OpenAI, Gemini), Facebook and WhatsApp Business API automation, or a WooCommerce plugin that needs untangling. Open to both scoped project contracts with clients and full-time remote engineering roles within product teams.

Are you available for remote work and team roles?+

Yes. I am available for full-time remote engineering roles, dedicated contract collaboration, and technical advisory with teams worldwide (USA, UK, Europe, Canada, Australia). English communication with flexible overlap across US/EU business hours.

What does working with you actually look like day-to-day?+

For product teams: GitHub PRs with clear descriptions, structured code reviews, async stand-ups via Slack or Linear, and blockers raised before they become delays — Agile and Scrum comfortable. For project clients: a defined scope before any code is written, concise weekly progress updates, and no surprises close to deadline.

Can you work with an existing codebase or legacy system?+

Yes — legacy refactoring and structured code review are among my core strengths. I have inherited and restructured systems built on unorganised plain PHP, poorly structured Laravel applications, and unmaintained WooCommerce plugins. I identify the highest-risk areas first, stabilise them, then incrementally improve architecture without rewriting everything at once.

How quickly will I hear back?+

I reply to enquiries within four hours on business days, and most projects can start within 48–72 hours of agreeing the scope.

How do you document and hand off your work?+

Every engagement ends with full source in your GitHub or GitLab, a README covering local setup and deployment, database migrations and seeders, a Postman collection for every endpoint, and inline comments on non-obvious logic. For team roles, I contribute to wikis, ADRs, and onboarding docs as a normal part of the workflow. You own 100% of the code.

09 — Contact

Let's build something that holds up.

Hiring for a full-time remote role, looking for dedicated team collaboration, or have a project that needs scaling? Drop a message or reach out directly.

Direct Channels
Emailhello@polash.link WhatsApp+880 1791 296967
LocationMymensingh, Bangladesh
ResponseWithin 4 hours, business days
Send a Project Brief