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Fiverr Pro
English
$
USD
I will develop a custom shopify app, checkout extension or shopify function
Zenkai Services
About this gig
Shopify only. Nothing else.
This is the work no app on the App Store actually sells and no theme editor can do. Custom apps, Shopify Functions, checkout UI extensions, and the API integrations that make Shopify agree with your other systems.
What I build here:
- Shopify Functions: custom discounts, shipping rules, payment rules, cart transforms
- Checkout UI extensions: fields, upsells, delivery instructions, custom validation
- Private and custom apps with a real admin interface inside your Shopify admin
- Integrations with your ERP, CRM, 3PL or warehouse over the GraphQL Admin API
- Webhooks that retry instead of silently failing at 2am
- Rescue work on a half finished app your last developer walked away from
Three of my own apps are live on the Shopify App Store and I support them daily. Same hands, same code.
Before you order, message me what you need. I will tell you if a Function solves it in a day, if it needs a full app, or if an existing app already does it and you should just buy that. If it is not worth building, I will say so.
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 Zenkai Services
Zenkai Services
Custom Shopify apps, checkout extensions and Shopify Functions
- FromIndia
- Member sinceAug 2026
Languages
Hindi, English, Spanish
Shopify only. Nothing else.
I build what Shopify won't do out of the box: custom apps, checkout extensions, Shopify Functions, theme work, API, integrations.
Three of my own apps are live on the Shopify App Store, supported daily. You get someone who has already shipped, not someone learning on your budget.
Work I take most often:
- A feature no app on the App Store actually sells
- "That isn't in the theme settings"
- Shopify and your ERP, CRM or 3PL disagreeing on stock
- A half-finished build your last developer walked away from
Send me your store URL and I'll tell you what it takes.
FAQ
Do I need Shopify Plus for this?
For most of it, no. Shopify Functions, custom apps and API integrations work on all plans. Only checkout page UI extensions need Plus. Thank You and Order Status page extensions work without it.
Who owns the code?
You do. I hand over the full repository, deployment steps and documentation. No lock in, and no monthly fee to me for the app to keep running.
Where does the app run and who pays for hosting?
A custom app needs a host. I can deploy to your own Vercel, Fly or AWS account so you own it, and advise the cheapest setup for your traffic. Hosting is usually a few dollars a month.
Can you fix an app another developer left unfinished?
Yes, that is a regular job here. Send me the repository and what is broken. I will read it first and tell you honestly whether fixing it or rebuilding it is cheaper before you order.
