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Shafat Mahmud K.
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Shafat Mahmud K.

WordPress Plugin Developer | Custom REST APIs & Backend Architecture

Need a custom WordPress plugin built from scratch without bloat or security vulnerabilities? Off-the-shelf plugins often slow down your database, create security risks, and break during core updates. I engineer clean, scalable, object-oriented PHP plugins and custom REST API endpoints designed to perform under heavy traffic. With a 100% Job Success Score (JSS) and Top Rated status, I help agencies, SaaS founders, and businesses extend WordPress functionality cleanly and securely. ━━━━━━━━━━━━━━━━━━━━ 🛠 CORE BACKEND & PLUGIN EXPERTISE ━━━━━━━━━━━━━━━━━━━━ • Custom Plugin Architecture: Built from the ground up using WordPress Coding Standards (PSR-compliant, OOP). • Custom REST API & Webhooks: Seamlessly connecting WordPress with external CRMs, payment gateways, ERPs, and third-party APIs. • Custom Post Types (CPT) & Advanced Custom Fields (ACF Pro): Tailored data structures without page-builder overhead. • Performance & Database Optimization: Query optimization, custom indexing, caching layers (Redis/Memcached), and transient API caching. • Bug Diagnostics & Security Hardening: Fatal error fixes, white-screen recovery, conflict isolation, and vulnerability remediation. ━━━━━━━━━━━━━━━━━━━━ 💼 EXAMPLE RECENT DELIVERABLES ━━━━━━━━━━━━━━━━━━━━ • Zero-Plugin Custom Architecture: Built dynamic features using pure core PHP/JS hooks, eliminating unnecessary plugin bloat and improving server response time. • Complex API Integration: Connected automated data sync between external platforms and custom WordPress dashboards with zero downtime. • Migration & Database Cleanup: Safely migrated legacy platform data into native WordPress structures while preserving SEO permalinks. ━━━━━━━━━━━━━━━━━━━━ 🛒 WOOCOMMERCE & STORE CAPABILITIES ━━━━━━━━━━━━━━━━━━━━ • Custom Checkout & Funnel Tuning: Streamlined 1-page checkout flows, custom billing fields, upsells, and payment gateway integrations (Stripe, PayPal, regional gateways). • Core Web Vitals & Speed Optimization: Achieving 90+ Google PageSpeed scores, sub-second TTFB, asset minification, critical CSS generation, and database bloat removal. • Custom Product Logic: Dynamic pricing rules, bespoke product configurators, inventory webhooks, and subscription setups. • Platform Migrations: Flawless store migrations (e.g., OpenCart, Shopify, or Magento to WooCommerce) preserving customers, order history, and product SEO. • High-Traffic Scalability: Ensuring smooth performance during flash sales and product drops without server timeouts. ━━━━━━━━━━━━━━━━━━━━ 📈 MEASURABLE IMPACT DELIVERED ━━━━━━━━━━━━━━━━━━━━ • Speed: Cut load times from 3.8s down to under 1s, directly improving mobile conversion rates and Google Core Web Vitals. • Store Migration: Executed complete multi-category store migrations without data loss, broken cart sessions, or dropped search engine rankings. • Reliability: Fixed fatal checkout errors and database locking issues for active e-commerce brands. Ready to build your plugin the right way? Send me a message with your project scope or wireframes, and let's get started.

🇧🇩Gazipur, Bangladesh$15/hr100% JSS5.00 (10)Since Jun 2021
GlobeUpwork

Earnings and projects

MRR
$17

Last 6 months ÷ 6

World#167,260 / 412k
🇧🇩Country#6,270 / 15.0k
Revenue, last 30 days
$0

Last 6 months: $99

Total earnings
$3.4k

Billed in all: $3.5k

World#288,352 / 412k
🇧🇩Country#9,920 / 15.0k
Per project
$187

$25 in the last 6 months

World#269,193 / 412k
🇧🇩Country#8,925 / 15.0k
Projects, last 6 months
4

Across 5 contracts

60% fixed40% hourly
World#51,813 / 412k
🇧🇩Country#2,836 / 15.0k
Projects in all
18

Across 19 contracts

89% fixed11% hourly
World#143,608 / 412k
🇧🇩Country#8,981 / 15.0k

Earnings, last 30 days

$3.5kNothing earned in the last 30 daysBilled in all, before Upwork's fee · drag across the chart to see what was earned in any stretch
$3,400$3,450$3,500$3,550Oct 8Oct 23Nov 7

Skill rankings: Top 31% in MySQL

Ranked by MRR among everyone on Upwork with the skill.

  1. #109Database Optimization229 freelancers · 🇧🇩 #9Top 48%
  2. #234Plugin Customization549 freelancers · 🇧🇩 #8Top 43%
  3. #341Advanced Custom Fields Plugin555 freelancers · 🇧🇩 #27Top 61%
  4. #500Bug Fix1,157 freelancers · 🇧🇩 #37Top 43%
  5. #626Plugin Development1,324 freelancers · 🇧🇩 #46Top 47%
  6. #632WordPress Security1,088 freelancers · 🇧🇩 #102Top 58%
  7. #1,725Back-End Development4,183 freelancers · 🇧🇩 #42Top 41%
  8. #2,314REST API5,062 freelancers · 🇧🇩 #70Top 46%