Please contact me only if you have knowledge of the 6amMart project. I already run the full 6amMart stack in production—Flutter apps for customers, vendors and delivery riders plus the standard web admin panel—but Paytm is still missing from the checkout experience. My Paytm merchant credentials are live and I have the official Paytm Flutter SDK ready. The job is to weave that gateway seamlessly into two apps: • the customer-facing Flutter app at checkout, and • the delivery-man Flutter app wherever wallet/collection payments are triggered. I need every Paytm-supported method I explicitly use today—credit card, debit card and UPI—showing inside the normal payment sheet, with proper callback handling so orders update instantly on success or failure. If additional Paytm options (such as the wallet) can ride on the same implementation, feel free to expose them, but they are not mandatory. Backend changes are fair game. If new endpoints or webhook listeners are required to create transactions, verify signatures, or reconcile orders, build them and wire them into the existing 6amMart Laravel/PHP API layer. Keep the codebase clean, follow the project’s naming conventions and supply concise inline comments. Deliverables - Updated Flutter code for both apps with Paytm fully integrated and switchable via the existing payment list - Any new or modified API routes, controllers and models, fully tested in staging and pushed to Git - Step-by-step setup notes so I can replicate the integration on another environment - One round of post-go-live support to squash edge-case issues (timeouts, duplicate callbacks, etc.) Acceptance criteria 1. Customer can choose Paytm, pay with credit card, debit card or UPI, and receive an in-app success screen. 2. Order status, payment ID and reference are written back to the 6amMart database with no manual refresh. 3. Delivery-man app reflects Paytm transactions the moment they clear. 4. All sensitive keys are kept in .env or secure storage—nothing hard-coded. 5. Build compiles and runs on both Android and iOS. If you can own the entire flow—Flutter front-end, Paytm SDK wiring, and backend hooks—let’s get this merged quickly.