Subiekt nexo integration

OpenLinker handles your orders, while invoices and receipts are created in Subiekt nexo

Subiekt nexo PRO stays where you keep your sales records, under your own numbering. When the buyer pays, OpenLinker picks the document itself: with a tax ID (NIP), an FS invoice; without one, a PA receipt. There’s always one document per order, and the status from Poland’s national e-invoicing system (KSeF) comes back to OpenLinker.

Let’s talk about your rollout Try the demo

To get started you need:Subiekt nexo PRO with Sferaa Windows computer running Subiekt

0 zł licence
No fee per order
You install it yourself, or we do it for you

Order

paid

marketplacesyour shop

paid →↓

OpenLinker

handles the order, picks the document

FS or PA →↓

←↑ KSeF status, PDF

Subiekt nexo PRO

sales records, your numbering

with a tax ID: FS invoicewithout a tax ID: PA receipt

In short. OpenLinker is open-source order management software with a 0 zł licence that creates invoices and receipts for your orders in Subiekt nexo PRO, under your own numbering. With issuing after payment, an order with a tax ID gets an invoice, and one without gets a receipt. Subiekt nexo sends the invoice to KSeF. This is a different integration from the Subiekt GT one.

Sound familiar?

You look for the tax ID on every order

You open the order, check whether the buyer gave a tax ID, and only then choose an invoice or a receipt in Subiekt. At a hundred and fifty orders, that’s a whole day of small decisions.

One sale, two documents

An export runs twice or the connection drops, and you’ve got a duplicate. You cancel it, then explain to your accountant where it came from.

The KSeF status lives in another program

Subiekt has sent the invoice to KSeF, but you work on orders somewhere else. To check whether it went through, you jump between windows.

Tuesday: 150 orders, each with one document

09:12The order is paid and the buyer gave a tax ID. Invoice FS 175/2026 is created in Subiekt nexo.
09:14Two minutes later a private buyer pays, with no tax ID. Receipt PA 312/2026 is created.
13:40A payment notice for the first order arrives again. The invoice already exists, so a second one isn’t created.

Documents from OpenLinker, Tuesday 150 orders Example

Order	Channel	Tax ID	Document	KSeF
#5531	Allegro	yes	FS 175/2026	accepted
#5532	shop	no	PA 312/2026	-
#5534	ERLI	no	PA 314/2026	-
#5535	shop	yes	FS 176/2026	accepted
#5679	shop	yes	FS 215/2026	sent

FS 41, PA 109, 150 in total. No order has two documents. KSeF: 38 accepted, 3 on their way.

Order #5531 One document

Buyera company, tax ID given at purchase

Documentinvoice FS 175/2026

KSeF statusaccepted

Second payment, 13:40no second invoice created

150 times “invoice or receipt?”, and not once did you have to decide.

See it in the demo

The data in this example is made up: orders, companies and numbers.

What OpenLinker does for you

Paid orderA buyer with a tax ID gets an FS invoice, everyone else a PA receipt. The document is created in Subiekt nexo, under your numbering.
The same payment a second timeThe invoice already exists, so a second one isn’t created. The same goes for a double click.
Connection to the bridge dropsOpenLinker doesn’t send the document again just in case. You check in Subiekt and click Retry.
CorrectionIt’s created in Subiekt nexo, linked to the invoice it corrects.

Technical details

Documents: FS invoice, PA receipt, correction
Choosing the document: after payment, automatically by tax ID; when you issue by hand, you choose it
Numbering: assigned by Subiekt nexo, in your series
KSeF status: Subiekt sends the invoice; OpenLinker refreshes its status every 30 minutes, and an administrator can change that interval
PDF: a link on the document, when the bridge makes it available
Connection to the bridge: by default up to 60 requests a minute, at most 4 at once

Your rules run on their own

The document is created on its own after the order is paid or shipped, and rules decide where. For example:

How automations work in OpenLinker

Example rule

When

An order is paid

Only if

delivery country: Poland

Then

Issue a document in Subiekt nexo

Choose when the document is issued in Subiekt nexo

You decide when the document should be created. In every mode, one order gets one document.

For getting started and for unusual orders.

By hand

You open the order, choose an invoice or a receipt and click Issue. You decide the document type yourself.

When most orders are paid upfront.

After payment

The document is created on its own once the order is paid. With a tax ID, an FS invoice; without one, a PA receipt.

Using Subiekt GT? That’s a different InsERT program with its own integration, which also handles orders, product records and stock. Subiekt GT integration

You don’t have to take our word for it

You can check each of these yourself before you connect anything.

One document per orderAn invoice for an order with a tax ID, a receipt without one. A repeated event returns the existing document instead of creating a second one.See the Subiekt nexo integration code
Try the demoSign up for the demo and look through orders, shipments and documents on sample data before you connect your shop.Try the demo
The code is openYou or your implementation team can review the Subiekt nexo integration before you run anything.See the integration code
Nobody can take the licence away from youApache 2.0 can’t be revoked, and no feature sits behind a subscription. Any developer can keep building on the code.Licence

What you’ll pay each month

You pay nothing for the OpenLinker licence, however much you sell. You pay for the server, and its price grows with your traffic, not with each order.

Orders a month	Roughly per day	Server, estimated
up to 1,000	about 30	about 150 zł / month
up to 5,000	about 150	about 300 zł / month
up to 10,000	about 300	about 1,000 zł / month
up to 25,000	about 800	about 2,000 zł / month

The server figures are estimates from OpenLinker’s pricing. Add backups on top.

Bills that stay as they are

Subiekt nexo PROthe InsERT licence you already have
Sfera for Subiekt nexoan InsERT add-on for the Subiekt you bought, priced by InsERT
Windows computerthe one Subiekt already runs on
HTTPS certificate for the bridgecan be free, set up by whoever does your setup
OpenLinker bridge0 zł, like all of OpenLinker

Who sets it up

Yourself

Who sets it up: You or your implementation team. One command and the setup wizard are all it takes.
Who looks after it day to day: You
What you pay: The server from the table above

Installation guide

With an implementation partner

Who sets it up: An implementation agency of your choice
Who looks after it day to day: The partner, backed by us under an SLA
What you pay: The server and the partner’s service, at the partner’s prices

Ask about a partner

With us

Who sets it up: Us
Who looks after it day to day: Us
What you pay: The server and maintenance, priced individually

Ask for a quote

No agency? We’ll set it up with you and help you move over from your current system.

All integrations run on the same server, so adding another one doesn’t mean another subscription.

Allegro ERLI Shoper PrestaShop WooCommerce All integrations

Who helps you

From setup to API changes, at every stage you know who is looking after it.

At the start

Getting set up

Who: You, a partner or us

You get a setup wizard and a step-by-step guide. If you’d rather not do it yourself, an implementation partner or we will set it up. We’ll set it up for you
When something stops working

Support under an SLA

Who: Us

You can report an outage that stops your sales at any time, weekends included. We take technical questions on working days from 9:00 to 17:00 and reply on the next working day. SLA levels
When InsERT or a marketplace changes something

Updates

Who: Us

We adapt the integration to API changes, and the fix ships in the next OpenLinker release. You install it yourself, or a partner or we do it for you.

Who to call for what

When something isn’t working, you know straight away who will fix it.

The Subiekt nexo PRO licence and the Sfera add-on, how the program works and its updates: InsERT or its partner
The Windows computer that runs Subiekt and the bridge, the fiscal printer, the content of your documents: Your company
The bridge and the link between orders and Subiekt: choosing the document, one document per order, KSeF status: OpenLinker

Your installation belongs to you: it runs on your server, your orders and customer data sit in your database, and the code is open under the Apache 2.0 licence.

How to get started

On the computer running Subiekt nexo, start the bridge: yourself, with a partner or with us.
In OpenLinker, enter the bridge address and token, and the wizard checks them.
Choose when the document should be created, and issue your first one as a test.

Want to try it first? Start on Subiekt’s demo database, which has Sfera built in.

Rather not do it yourself? We’ll set it up for you. Step-by-step guide.

Questions about the Subiekt nexo integration

Who sends the invoice to KSeF?

Subiekt nexo, just as it does now. OpenLinker reads the status and shows it next to the order.

Can I issue an invoice without a tax ID, or a receipt even though there is one?

Yes, by hand. On the order you choose the document type yourself and click Issue.

Will the receipt be a fiscal one?

Yes, when a fiscal printer is connected to Subiekt. Without one, a PA receipt is created in the program, but not a fiscal receipt.

Will orders, product records and stock reach nexo too?

No. You handle orders in OpenLinker, and nexo receives the sales documents: invoices, receipts and corrections. Product records and stock are linked to OpenLinker by the Subiekt GT integration, which is a different InsERT program.

Does it work with Subiekt nexo without PRO?

The integration is for the PRO version. Have a different one? Get in touch before you roll it out, and we’ll check whether your licence gives you access to Sfera.

OpenLinker at a glance

What it is: Open-source order management and e-commerce integration software
Licence: Apache 2.0, 0 zł
Fee per order: None
Where it runs: On your own server, or set up by us or an agency
Code: github.com/openlinker-project/openlinker

Practise on Subiekt’s demo database

You’ll start by issuing by hand on the demo database, where the KSeF status is only a test, so you can’t settle anything by mistake. On a call we’ll agree where the bridge goes and who installs it: you, your partner or us.