A complete counter.
On the hardware you already have.
Point of sale for hardware stores, cafés, parts shops, pharmacies, and restaurants. Sell offline. Stock that does not lie. Loyalty at the ticket. Electronic invoicing through the shop’s own tax identity — not ours.
- ✓ Works when Wi‑Fi dies (local sqlite)
- ✓ Pick the business type — hardware, café, parts, pharmacy — starter catalog appears
- ✓ Cash, barcode, reports that match the money in the drawer
- ✓ Live app: pos.fluxsoftlabs.com
List prices below are unofficial until locked in HOW-WE-WORK. 14-day trial with card. Cancel before day 15 and you are not charged.
Pick how you sell
Hardware store
SKU, barcode, cost vs price, stock ledger, cash. Kitchen off.
Café / restaurant
Name on cup, barista queue, tables, modifiers — only if you pick that type.
Auto parts
Fitment search: make / model / year + OEM cross-reference.
Pharmacy
Lots and expiry on the same catalog engine.
Retail
One register. Gift cards optional. Reports that match cash.
Take any payment at the counter
Cash, card, gift card
Cash is live. Card button is ready for the shop’s own gateway — not a US acquirer.
Offline
The sale is on the device. No invented cloud hostname.
Loyalty
Points and punches on the ticket. One chip, not a course.
Stock that does not lie
Every in/out is an append-only ledger row.
Electronic invoicing — the Lithos pattern
Lithos (US firm) does not become the shop’s tax identity. They plug Infile, Megaprint, Cofidi, Felpflex into the shop’s SAT. We do the same. FluxSoft LLC (Delaware) does not emit FEL. The shop’s NIT + certificador keys go in Settings. The sale sends XML, comes back UUID + QR, prints on the receipt.
1. Shop has NIT
Pequeño contribuyente is enough. No sociedad anónima required.
2. Shop contracts a certificador
Infile, Digifact, Megaprint, or Guatefacturas. SAT phone app has no POS API.
3. Paste keys in FluxPOS
Settings → FEL. Provider, API key, NIT emisor, establishment code.
4. Sell as usual
Pay → certify (or queue if the net is down) → print receipt with UUID and QR.
Print the sale and the factura from the same counter
Lithos certifies the DTE, then prints UUID + SAT consult on the ticket. We do the same: Pay → Infile/Digifact answers → UUID, serie, NIT, SAT URL on the receipt. Browser / iPad: print dialog (PDF / AirPrint). Desktop app: ESC/POS USB or network, cash drawer kick if the printer supports it. No second program. No SAT phone app.
Learn and grow with each sale
Reports that match the drawer
Hoy = completed payments, not a stale order total. Cash in the till is the number.
Stock ledger
Every in/out is an append-only row. Hardware, parts, pharmacy lots — same engine.
Loyalty on the ticket
Points and punches at pay. One chip, not a course.
AI catalog (Premium list)
Import a list. The counter stays three taps. NASA stays inside.
How the money actually works
Square is a US bank + hardware store. Lithos is a US POS that plugs the shop’s local tax system. FluxPOS is Lithos-shaped: subscription + the shop’s NIT + the shop’s certificador. Public numbers below are theirs; FluxPOS list is unofficial until locked.
| Square (US) | Lithos (GT) | FluxPOS | |
|---|---|---|---|
| Software | Free / $49 / $149 per location | $19 Lite · $49 Pro /mo (yearly) | $19 / $49 / $99 (list, not locked) |
| How they get paid | 2.6%+15¢ in-person (Free) | Subscription. Shop’s gateway. | Subscription. Shop’s gateway. |
| SAT / FEL | No | Infile, Megaprint, Cofidi, Felpflex | Shop NIT + Infile / Digifact / Megaprint / Guatefacturas |
| Who emits the factura | — | The shop | The shop. FluxSoft LLC does not. |
| Print factura | US receipt | UUID + QR from their POS | UUID + serie + SAT consult on the same ticket |
| Hardware | Readers $59–$899 | Use yours | Use yours. Tablet PWA or desktop. |
| Offline | Cards: 24h then decline | Billing continues, then sync | Sale lives in sqlite on the device |
| Trial | 30 days Plus/Premium | 14 days, they say no card | 14 days, Stripe card, no charge today |
Square: squareup.com/us/en/pricing (US, Aug 2026). Lithos: lithospos.com/pricing Guatemala yearly (Aug 2026). FluxPOS $19/$49/$99 is the live list on this page — not a locked SKU. Andres sets the public number.
Current list (not locked)
We compare this list to Lithos (subscription) and Square (take-rate + hardware). Final public number waits Andres. Do not treat these as a locked SKU.
Trial, factura, hardware
Do I need Square hardware?
No. Use the tablet or computer you already have. We do not sell a card reader or a bank.
Does FluxSoft emit the SAT invoice?
No. The shop does, through their certificador. Same model as Lithos.
Where do I try it?
pos.fluxsoftlabs.com — pick Ferretería (or café, parts, pharmacy). Starter catalog appears. Skip AI import if you want the demo list.
Is the 14-day trial free?
Yes. Card on Stripe, no charge today. Cancel before day 15.