Next Web Business

Started in November 2025 as Billdesk, Next Web Business brings inventory, invoices, recurring billing and accounting registers into one application. Concurrent billing, tax calculations and document generation each introduce a different consistency problem.

I co-architected and implemented voucher, inventory, contact and financial-register modules. I independently built and deployed the document service, including its authentication, request contract, template selection and integration with the ERP.

The browser requests a PDF from ASP.NET Core. That service forwards authentication and tenancy context to Express to fetch hydrated document data. QuestPDF renders the selected template and returns PDF bytes to the browser. Documents are rendered on request rather than served from a PDF cache.

FIFO stock consumption, voucher updates and inventory ledger entries run in MongoDB transactions. Conditional quantity checks protect stock adjustments when multiple users bill concurrently.

React gives immediate feedback with a 120 ms debounce on numeric input; Express recalculates totals before saving. Both sides apply the same GST rules: intra-state CGST/SGST splits and inter-state IGST, with HSN/SAC summaries. The server remains authoritative.

1static getTaxType(sellerStateCode, placeOfSupplyStateCode) {2  if (!sellerStateCode || !placeOfSupplyStateCode) return "CGST_SGST";3  return sellerStateCode === placeOfSupplyStateCode ? "CGST_SGST" : "IGST";4}

One production customer account uses the application with 50+ active sub-users. GST reconciliation remains manual: accountants compare registers with portal reports. This is not an automated government-portal integration. Customer records, live endpoints and private source repositories are not exposed.