1 Brief received
You receive a reply with clarifying questions
You describe what the plugin should do — in the form below or by e-mail. We read it, check whether a good ready-made plugin already exists, and reply — usually within one working day.
Custom WordPress plugin, made to order
We write WordPress plugins to order: whatever feature your site is missing, built from scratch and fitted to it. You describe what it should do — you get a fixed price for an agreed scope, a finished plugin with documentation, and the code to keep.
A fixed price for an agreed scope. We usually reply within one working day.
Request a quote
Describe what the plugin should do. We do not need a specification — one plain sentence about what does not work today, or takes too long, is enough.
Description
A plugin is a program that adds to WordPress a feature it does not have — and neither does any ready-made extension. We write that plugin from scratch, exactly for your site.
Any plugin — literally
If it can be done in WordPress, it can be done as a plugin: connect the site to the system you work in, give the shop rules WooCommerce lacks, build a panel for the team, automate what somebody does by hand today. The kinds beside this are the most common orders, not the boundary.
What we do not do
We do not copy other people's paid plugins, do not bypass licences, and do not build things that work against the site's visitors: spam, tracking without consent, hidden redirects.
Example integrations
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BaseLinker
Orders and stock in one place.
The plugin sends shop orders to BaseLinker and takes status changes back. Stock moves both ways, so you do not sell what is no longer on the shelf. Status and warehouse mapping is set up around how you actually work.
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Allegro
The shop and the Allegro listings stop being two jobs.
Shop products are tied to Allegro listings, with prices and availability kept honest on both sides. Orders from Allegro land in the shop panel like any other. Which listings sync, and how often, is your decision.
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InPost
The pickup point chosen in the basket, the label from the panel.
The customer picks a locker without leaving the basket, and you print a label in one click from the order list. The tracking number goes back onto the order and out to the customer by e-mail.
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PayU
A payment that does not send the customer somewhere strange.
PayU goes into the basket alongside BLIK and cards, and the payment status updates the order by itself. Anything unusual — deposits, part payments, prepayment for a service — is described in the quote before a line is written.
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Przelewy24
The same payment, a different provider.
Przelewy24 is wired in exactly as PayU is: methods in the basket, confirmation back onto the order, refunds from the panel. You can run both providers at once and decide which one handles which method.
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Stripe
Cards, subscriptions and selling abroad.
Stripe earns its place where you sell repeatedly or outside Poland: cards, subscriptions, recurring charges. The plugin makes sure a notification from Stripe changes the order exactly once, even when it arrives twice.
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GUS / REGON
Company details from a tax number, without retyping.
The customer gives a Polish tax number in the basket or in a form, and the plugin fetches the name and address from the register and fills the fields in. A shorter form and fewer typos on the invoice.
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KSeF
The invoice goes where it has to go anyway.
The plugin prepares the invoice in the format KSeF requires, sends it, and records the reference number on the order. When it is sent, and which documents go, is fitted to your paperwork rather than the other way round.
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Fakturownia
The invoice writes itself once the payment lands.
As soon as a payment is recorded the plugin creates the document in Fakturownia and mails it to the customer, keeping the link on the order. Your numbering, series and rates stay exactly as they are today.
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wFirma
The same, if your books live in wFirma.
Orders arrive in wFirma as sales documents with your own descriptions and rates. Corrections and refunds too, so nobody in accounts has to straighten things out afterwards.
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Google Sheets
A spreadsheet that fills itself in.
Orders, form submissions or any other event you name land in a sheet as they happen. Useful when the team works in spreadsheets and would rather not log into the shop at all.
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HubSpot
A contact from the site, straight into the CRM.
A form submission creates the contact and the task in HubSpot, carrying which page and campaign it came from. Sales sees the customer's order history without switching to the shop.
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Slack
The notification where you are already looking.
A new order, a failed payment or a complaint arrives in the channel you name — with what the decision needs and a link to the rest. The rules for what is sent, and when, are yours to set.
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Notion
The database the team already works in.
The plugin appends records to a Notion database: enquiries, orders, content to prepare. Changes made in Notion can come back to the site as well, if that is what you need.
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Mailchimp
A sign-up that matches what the customer agreed to.
The address goes onto the right list together with the consent and its date, and tags say what the customer bought and where they came from. Without consent nothing goes out, and that is a rule in the code rather than a checkbox.
The list is illustrative. If a system has an API or an export, it can be connected.
Specification
Every plugin that leaves us contains:
| Structure | One plugin, one folder. Activation and deactivation leave no traces; uninstalling cleans up after itself. |
|---|---|
| Code standard | WordPress Coding Standards, PHP 7.4–8.x, checked automatically before every release. |
| Security | Capability checks, form tokens, input and output filtering, prepared queries — on every screen and in every endpoint. |
| Performance | No needless database queries, caching where it makes sense, long jobs in the background. |
| Translations | Every string ready for translation; English and Polish included, further languages on request. |
| Updates | A version number, a changelog, updates without losing settings or data. |
| Tests | Tests of the core logic plus a test on a copy of your site before launch. |
| Documentation | A guide for the administrator and a technical description for whoever works on it next. |
| Ownership | Code under a GPL-compatible licence. The repository and the ZIP are yours; no keys, subscriptions or phoning home. |
Order tracking
This is the road from brief to a working plugin. The times are typical for an average order; the exact ones come with the quote.
2 Quote and scope
You receive a document: what gets built, for how much, by when
You receive the scope in plain language, a fixed price and a date. The scope is a list: you know what is inside and what is not.
3 Order confirmed
You receive a schedule and one channel of contact
You accept the scope. We arrange access to a copy of your site (staging) — if you do not have one, we help set it up.
4 Build
You receive a short weekly progress report
We write the plugin. Questions are asked in one place so they do not take your time; once a week you get what is done and what comes next.
5 Testing on your side
You receive the plugin on a copy of your site to click through
We install on a copy of your site. You click through, report what you notice, we fix it. The scope does not change — unless we both want it to, and then the quote changes too.
6 Launch
You receive the ZIP, the repository, the documentation
Installation on the live site in an agreed window. We hand over the package, the repository and the administrator's guide. You pay for the finished plugin here on the site, by card, from a link in your e-mail.
7 After launch
You receive bug fixes, optionally ongoing care
Bugs within the agreed period are fixed at no charge. Further care, monitoring and development — separately, if you want them.
Compare
A ready-made plugin from the catalogue or one written to order? An honest side-by-side.
Ready-made
- Scope
- what its author foresaw
- Unneeded features
- usually plenty
- Cost
- a subscription, often yearly, per licence
- Performance
- generic, for every site
- Updates
- up to the author
- Support
- a forum or a ticket queue
- When
- today
Made to order
- Scope
- exactly what you need
- Unneeded features
- none
- Cost
- once, for an agreed scope
- Performance
- fitted to yours
- Updates
- in your hands, with documentation
- Support
- direct contact with the code's author
- When
- usually a week or two
When a good ready-made plugin does exactly what you need — use it. We will tell you so in our reply to your brief. Made to order makes sense when there is none, or when several would have to be joined into one.
Questions and answers
Really any plugin?
If it can be done in WordPress, it can be done as a plugin. There are three limits: we do not copy other people's paid plugins, we do not bypass licences, and we do not build things that work against the site's visitors.
Will the code be mine?
Yes. You get the repository and the ZIP package under a GPL-compatible licence. You can develop it yourself or with anyone else; the technical documentation is there for that.
I have a plugin that stopped working. Will you fix it?
Yes — that is the "Repair and rebuild" kind. We start with an audit and tell you whether it is cheaper to fix it or to write it anew.
What language will the plugin's panel be in?
English and Polish, ready to be translated into more. Documentation in English or Polish; other languages on request.
Do I need a developer on my side?
No. An administrator account on a copy of the site is enough. If you have no copy (staging), we will help set one up at your host.
What happens on the 30-minute call?
You pick a time in the calendar at the foot of this page, get a confirmation by e-mail, and we talk at the agreed hour. Half an hour is enough to describe what the plugin should do and to hear straight away whether it can be done more simply, whether it needs a different approach, and roughly what that means in time and money. The call is free and optional — if you would rather just write the brief, we answer the same working day.
How does payment work?
A fixed price for an agreed scope, with a VAT invoice. You pay for the finished, handed-over plugin here on wordpressplugin.pl — by card through Stripe, from a link we e-mail you. Instalments and dates are agreed in the quote; a change of scope midway is a new, open quote, never a surprise on the invoice.
Who builds this?
Castomo prosta spółka akcyjna of Wrocław, Poland — the company behind the castomo ecosystem. We have already released and maintain a WordPress plugin of our own, Castomo WordPress Link.
What happens to the brief?
It goes to our operations inbox and is used only to answer your enquiry. We delete it at your request.
Book a call
Thirty minutes about what the plugin should do. Pick a time; the confirmation arrives by e-mail.
The call is free and commits you to nothing. If it turns out a ready-made plugin is enough, we will say so plainly rather than sell you work you do not need.
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