Sales invoicing, purchase bills and GST-ready documents
Sales invoices, returns, credit and debit notes on the sell side; purchase bills, invoices and returns on the buy side — every line computing its own GST from the item master, not the operator’s memory.
GST% and HSN pulled from the item — never typed, never guessed.
Per-warehouse pricing, so one item can price differently by location.
CGST/SGST/IGST splits auto-post to whichever accounts are configured.
Freight, rounding and discounts tracked apart from what was sold.
Every invoice prints exactly what was entered — nothing re-typed.
Posting an invoice updates stock instantly — no separate entry.
Overselling a warehouse is blocked at the moment of posting.
How people use it
The journeys it was designed around
A sales team memberRaise an invoice a customer’s accountant will accept without questions
Picks the customer and adds items — each line pulls its GST% and HSN code from the item master rather than being typed by hand.
CGST/SGST or IGST splits automatically based on whether the customer is in-state or out-of-state.
The invoice checks live stock availability for the fulfilling warehouse and refuses to post if the quantity would oversell it.
The invoice prints exactly what was entered, with nothing re-typed for the customer’s copy — and the warehouse’s stock is already down by the quantity sold.
An accountantIssue a credit note that keeps the GST trail intact
Opens Credit Note against the original sales invoice rather than starting a blank document.
The credit note reverses the exact GST split of the original line items, not a flat percentage.
Keeps a running register a GST return can be reconciled against.
How it is built
Implementation and the rules real users find
Under the hood
Tax and pricing follow the item, always — never the operator’s memory.
GST accounts are set once, referenced everywhere — no code changes to repoint them.
Freight, rounding and discounts stay separate from what was actually sold.
The printed invoice and the saved record are always the same document.
Posting moves stock through the exact same check Goods Receipt uses — reversible, exactly, on un-post.
The rules real users find
A return reverses the exact GST split — never a flat credit.
GST rates are always resolved live, not cached from an old price list.
Two rates for one item across two warehouses isn’t a mistake — it’s by design.
Overselling a warehouse gets rejected outright, invoice screen or not.
The screens
Taken from the live product
Click any shot to enlarge.
The sales invoice list — history, status and totals at a glance.Purchase Bill entry, posting the buy-side mirror of the sales invoice flow.Credit Note — reversing an invoice’s GST split exactly, not approximately.Debit Note, the purchase-side equivalent for adjustments against a supplier.
The rest of the platform
All 5 modules
These were built on one schema and one permission model, which is the only reason all 5 of them could ship together.
SigmaticAI is led by Ketan Khamgaonkar — an IIT Roorkee M.Tech who went on to PhD research at IIT Bombay before spending four years building AI automation, agentic systems and full web and mobile products. On every project you talk to the person writing the code.
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