I will develop custom private shopify apps and fix app bugs


About this gig
Fiverr Gig Description Shopify Custom App Development & Bug Fixes
Need a custom Shopify app built from scratch, or is an existing app throwing errors, breaking checkout, or misbehaving after an update? I build and fix private/custom Shopify apps using Shopify CLI, Admin API, Storefront API, and Web Pixels production apps, not templates, not quick hacks.
WHAT I CAN BUILD/FIX:
- Custom private apps (Admin API, Metafields, Webhooks)
- App bugs broken installs, auth/OAuth errors, API rate-limit issues, crashing scripts
- Checkout/Web Pixel extensions & app embeds (theme app extensions)
- COD order flows with OTP phone verification (anti-fraud)
- Courier & payment gateway integrations (Pathao, SteadFast, bKash, SSLCommerz, EPS)
- Order automation, fraud checkers, marketing/SMS modules
- Migrating deprecated APIs (Checkout.liquid Extensions)
RECENT WORK:
Built a full COD order-management app for a children's toy Shopify store, replacing native checkout with a custom Buy Now popup delivered as an app embed. It handles OTP verification via SMS to block fake COD orders before they fire Meta/Google/TikTok purchase pixels, plus fraud checking, multi-courier dispatch etc.
Respect third-party rights
Please be aware that it is against Fiverr's policies for sellers to include themes, templates, or any other elements that infringe third-party rights or applicable laws in the delivered work. Read more about in our Guide to Responsible Digital Creation.
Get to know Fahad Hasan
7 plus years building Shopify apps, stores and mobile apps
- FromBangladesh
- Member sinceMar 2022
- Avg. response time1 hour
- Last delivery2 years
Languages
Bengali, English, Hindi, Urdu
My Portfolio
FAQ
Do you need admin access to my store?
Yes, staff/collaborator access or a dev store, whichever fits.
Can you work with my existing codebase?
Yes, send the repo/zip and I'll scope it in the requirements.
Do you build public (listed) apps?
Focus is custom/private apps for a single store; can discuss public apps separately.
