Our Blog

Flaem: panel, store and licences for a hosting company in one installation

Offers with plans, hardware tiers, coupons and software licences sold in the same panel where the client runs their server

Flaem sells game servers, VPS and software licences from a store that is part of the panel rather than a bolt-on module. Here is what an operator gets, and what happens when the Flaem licence payment is late.

KSeF for foreign companies with a Polish VAT number

When a company based outside Poland has to issue e-invoices in KSeF, why its purchase invoices can arrive only there, and how it gets access to the system

A Polish VAT number alone does not put a foreign company under KSeF: what decides is a fixed establishment in Poland that takes part in the sale. Purchase invoices are another matter, because a Polish supplier may leave them in KSeF alone.

Plazer in the browser: what loads at start and what waits until it is needed

A Rust encryption core shipped as WebAssembly and split into a start part and the rest, and camera effects fetched on first use: figures measured on the web version

Plazer's sign-in screen is 105 kB, while the camera background effect alone weighs 3.76 MB. We show what the browser fetches at start, what waits for first use, and how the WebAssembly core is split in two from the linker's relocations.

Taking over a project from another vendor: what we check before we quote

Secrets, accounts, a clean install, dependencies and a backup: where taking over an app or website starts, and what the review report gives you

We quote the rest of someone else's project after a review, because only then is it clear how much work is left. Here is what we check before the first change to the code, and why we start with passwords and keys.

Channel manager and Booking.com: how a hotel connects its own booking system

What a channel manager does, why a hotel reaches Booking.com through one, and when a reservation lands in the front desk's inbox instead of the calendar

The Booking.com API is for Connectivity Partners, so a hotel with its own website usually connects through a channel manager. We show when a reservation ends up in an email instead of the calendar, and how the integration prevents it.

How much does an e-learning platform cost: hosted, licensed or custom

A subscription with plan limits, a yearly WordPress plugin licence or a platform you own: the costs compared, and what video adds on top

A hosted course platform is a subscription with a cap on products, and on Teachable's cheapest plan also a cut of each sale. A licence is a yearly fee plus hosting. We compare the three routes on Teachable, Kajabi and LearnDash pricing and work out what video costs.

How much does website maintenance cost per year

The domain and hosting are only part of the bill: shorter TLS certificates and the end of PHP 8.2 support bring work in 2027 on dates someone else has set

In 2027 the domain and hosting come with work on other people's deadlines: TLS certificates valid for 100 days at most and PHP 8.2 without security fixes. Here is what goes into the budget and what a maintenance plan covers.

How much does a website or online store migration cost

URLs that bring traffic, store data, customer passwords and a domain change: what sets the price of a move, and what you keep paying for after switch-over day

A migration is priced by the URLs that bring visits today and the data that has to arrive intact, not by the number of menu items. Here is what weighs in the quote, and why the move does not end on switch-over day.

A Discord alternative for businesses and communities: what to compare

Who can read the messages, where the server runs and how to move a community to a new messenger

Discord encrypts voice and video calls end to end, but not text messages, and it has no plans to change that. We compare it with Matrix and Plazer on the points that matter to a business or a community.

Migrating from VMware to Proxmox VE: plan, downtime and costs

The ESXi importer built into Proxmox VE, live import, the machines that need a plan of their own, and a subscription priced per CPU socket

Since version 8.2, Proxmox VE imports virtual machines straight from VMware ESXi, live if you need it. We show how downtime shrinks, which machines we plan separately and what drives the cost of a Proxmox subscription.

WHMCS alternatives: what to check before you switch your hosting billing system

Licences priced by active clients, owned and open source options, moving clients and invoices, and local payments and e-invoicing for hosts selling in Poland

WHMCS prices its licence by active clients and by default moves you up a plan once you pass the limit. We set it against Blesta, Paymenter and FOSSBilling and list what to check before a host moves its clients, services and invoices.

How much does a custom CRM or client portal cost

Views, roles, sign-in, integrations and an audit log: what goes into the price of a panel, and how it compares with per-seat pricing

An off-the-shelf CRM bills every user every month, while a custom panel is quoted once, module by module. We show which modules weigh in a quote and what a sales team pays for a popular CRM over a year.

How much does a landing page cost, and when is one page enough

Section count, design, motion and the form set the price, while speed and tracking set how the campaign performs

A landing page has one job: a sign-up, a sale or an enquiry. We separate what raises its price from what raises campaign results, and show when a single page is enough instead of a company website.

How much does a mobile app cost in 2026, simple ones included

Screens, platforms and sign-in on the code side, developer accounts and store review outside it, plus what Apple and Google require in 2026

A simple app means a handful of screens, sign-in and push notifications, but store fees, review before release and new SDK versions are part of the bill too. Here is what sets the price at launch and what comes back after it.

Shoper, WooCommerce or a custom store: choosing a platform before peak season

Catalogue size, business pricing, custom code and updates: four questions that settle the choice faster than comparing themes

Pick a store platform by where it stops, not by what it offers on day one. We show the limits of Shoper's plans, what WooCommerce adds through extensions, and the kind of selling where a custom store is the route without workarounds.

BaseLinker vs Apilo vs Sellasist: choosing an order hub for multichannel selling

Plan prices at 1,000 orders a month, stock sync speed and the API your store or ERP talks to

Three multichannel tools for stores selling in Poland differ less in features than in how fast they push stock and what their APIs allow. We compare published prices at 1,000 orders a month and the request limits from their documentation.

Tauri vs Electron in 2026: size, updates and long-term upkeep of a desktop app

The system webview against a bundled Chromium, signed updates and the release cycle: what choosing a framework means for years of maintenance

Electron ships its own Chromium and Node.js inside every app, while Tauri uses the browser engine the system already has. We compare both on size, updates and upkeep, and say when each one wins.

Polish payment gateways compared: Przelewy24, PayU, Tpay, Paynow and Stripe

BLIK fees from the standard price lists, fixed charges, the cost on a PLN 100 order and what besides the fee decides which gateway to pick

Five gateways charge in three ways: a percentage plus a per-transaction fee, a lower percentage with a monthly package, or a percentage alone. We put the standard BLIK rates side by side and show which gateway wins at which basket size.

How much does an online store cost in 2026: a SaaS plan, WooCommerce or a custom build

Subscriptions, hosting, extensions, payment fees and further work: the cost of a store counted over years, not just at launch

The cheapest launch is not the cheapest store. We compare a SaaS plan, WooCommerce and a custom build by the fees that come back every month and every year, and show when a platform's percentage starts to cost more than your own code.

Website development contract: the clauses that protect both sides

Scope, changes, acceptance, code rights with fields of use, derivative works, library licences and warranty: what to check before you sign

Under Polish copyright law, a website contract that does not expressly transfer the rights gives the client only a licence. Here are the clauses that settle a dispute before it starts, and the provisions such contracts most often trip over.

Autoprefixer: grid gaps set with grid-row-gap and grid-column-gap survive inheritance

A rule that inherits grid-template-areas copied the gap only from grid-gap. A gap set with grid-row-gap and grid-column-gap was lost from the -ms-grid prefixes.

Carbon: round(3600) rounds to the full hour instead of only zeroing seconds

A numeric precision in round(), floor() and ceil() means a number of seconds, but from 60 upwards it never carried into minutes, hours and days. round(3600) only zeroed the seconds.

Concourse: task file vars are interpolated before the file is parsed

A var in a non-string field such as memory: ((container_mem_limit)) failed validation, because the task file was parsed before its vars were resolved. The issue had been open since 2020.

How to build a Discord bot in Python: from the token to slash commands

You create the application, invite the bot, write slash commands in discord.py 2.7.1 and run it in a container that comes back on its own after a reboot. Our mailcheck bot has the same layout.

How to build a Minecraft server store: payment and automatic delivery

Two ways to hand over an item after payment: a command over RCON, and a queue the plugin pulls deliveries from. We show both, with what each one cannot do, on the code of the store in Flaem.

How to host an SCP: Secret Laboratory server on Linux, step by step

You install the server with SteamCMD on Debian 13 or Ubuntu 26.04, run LocalAdmin in tmux, open the UDP port, set config_gameplay.txt and submit the server for verification. Following the Northwood tech wiki, including its two traps.

ILSpy: the decompiler no longer leaves a delegate cache field behind

For _ = (Action<int>)M; ILSpy produced output with a <>O.<0>__M field that does not compile. That spot now becomes a plain delegate construction.

InPost ShipX API step by step: shipment, label and statuses

You create a locker or courier shipment, wait for the offer to be paid, download the label and receive status changes by webhook. TypeScript code on Node.js, checked against the InPost documentation and sandbox.

Installing Pterodactyl step by step: the panel, Wings and the first server

You set up the Pterodactyl 1.15 panel on Ubuntu 24.04 with PHP 8.3, MariaDB, Redis and Nginx, then a Wings node on Docker that runs the game servers. Following the official documentation, in an order that needs no fixing afterwards.

KSeF API 2.0 step by step: sending an invoice from your own system

From the KSeF token to the KSeF number and the UPO: authentication, an online session, RSA-OAEP and AES-256 encryption and sending an FA(3) invoice. Python code run against the Ministry of Finance test environment.

Monolog: RedactingFormatter now hides secrets nested in arrays

A password inside an array under a sensitive key leaked into the log when PsrLogMessageProcessor had already put it into the message. The formatter now collects every string in such an array.

Pelican Panel: updating a plugin no longer crashes

Updating a plugin in the Pelican panel died with \"Call to a member function query() on null\", because the code refreshed a model whose connection it had just reset. It now loads a fresh record.

PHPMailer: QUIT no longer ends up inside an interrupted message

When sending broke off in the middle of the DATA command, PHPMailer sent QUIT, the server took it as another line of the message and kept waiting. Now the connection is simply closed in that case.

Przelewy24 REST API: a payment from registration to verification

You register the transaction, send the customer to Przelewy24, receive the notification and confirm the payment with verify. Without verification the money never reaches you. PHP 8 code checked against the sandbox.

Pterodactyl vs Pelican in 2026: which game server panel to choose

Licence, panel database, admin area, plugins and in-place migration: how Pterodactyl and its fork differ today

Pelican began as a fork of Pterodactyl and can take over its database in place, but it ships under a different licence, with different requirements and its own plugin system. We compare both panels from the code side, where we have a fix merged.

Software and e-commerce glossary

Short, concrete definitions of terms from software projects, each with an example from our work: KSeF, API, webhooks, PWA, hreflang, MVP and more.

Sonic: TRIGGER backup works while a store is in use

Backups in the Sonic search backend failed right after data was written, because RocksDB will not open a database that is already open in the same process. The backup now uses the open store.

vscode-neovim: visual selections no longer cut an emoji in half

A selection ending on an emoji or a character like 𝕜 stopped in the middle of a UTF-16 surrogate pair. The end of the selection now steps over the whole character.

Your first Minecraft plugin on Paper 26.3: from project to test server

You set up a Gradle project with Paper API 26.3 and Java 25, write a command and an event handler, and start a test server with one command. Following the PaperMC documentation, including what changed in 26.1.

Zed: a slow ChatGPT model catalog no longer blocks sign-in

The ChatGPT subscription model catalog can take 30 seconds to answer, while Zed waited 5 and hid the account's models. Sign-in now waits 5 seconds and the catalog finishes loading in the background.

What a KSeF integration costs: what you pay for with API 2.0

What changes the scope of connecting a store, billing system or ERP to Poland's e-invoicing system through API 2.0, and the upkeep as the Ministry of Finance ships new API versions.

Sending one invoice to KSeF is the cheapest part of a KSeF integration. The price is set by your data, your invoice types, the number of tax IDs, sales peaks, offline modes and new API versions. Here is what weighs most.

How much does a custom Discord bot cost: from one script to a system with a panel

Five levels of a bot, from webhook notifications to a system with a browser panel, the Discord API limits it has to respect and what the project price covers.

What a Discord bot costs depends on what it has to talk to, not on how many commands it has. We split a quote into five levels and go through the Discord limits that decide whether a bot still works six months later.

Five fixes in Proxmox VE: what we changed in the interface and how a patch gets through pve-devel

The .img image format, the fakepath prefix, resource mapping names, IPSet aliases and IPv6 comments. Five Bugzilla reports closed by six commits.

The Proxmox team applied our fixes for five bugs in the Proxmox VE web interface, from .img image imports to the IPSet alias list. What each one changes and how a patch reaches the main branch through the pve-devel mailing list.

API integration: how to connect your website, online store or admin panel to ERP, CRM, accounting and payments

Data map, webhooks, synchronisation, queues, idempotency, error handling and key security: what has to work before an integration goes into production

Connecting two systems through an API is the smaller part of the job. The bigger part is handling what happens when a webhook arrives twice, the ERP does not respond and a token expires in the middle of the night. How to design an integration that survives all of that.

How to build an MVP: the first version of your product without burning through the budget

Hypothesis, scope, priorities, the list of things put off, measuring after launch and deciding whether to extend the code or rewrite it

An MVP is not a cheaper version of the full product, it is the cheapest way to find out whether anyone needs it. How to set the scope, where to save, what not to simplify, how to measure the result and when to rewrite the code.

The KSeF e-invoicing timeline and connecting your own system to API 2.0

Who issues e-invoices in KSeF and from when, what changes in the company, and how to integrate an online store, admin panel or ERP: authentication, sending and receiving invoices, limits, offline modes and QR codes

KSeF, Poland's National e-Invoicing System, has been mandatory since 1 February 2026, and from 2027 it will cover the smallest businesses too. The timeline, what changes in the company and a practical guide to integrating your own system with the KSeF API 2.0: certificates, sessions, limits, receiving invoices and fallback modes.

GDPR compliant website: forms, consent, cookies and privacy policy

Legal bases for contact forms and newsletters, a cookie banner that complies with Poland's Electronic Communications Law, analytics, third-party scripts, data processing agreements and the typical mistakes on company websites and online stores

GDPR on a website is not a checkbox under a form. How to pick the legal basis for a contact form and a newsletter, when you need cookie consent, what to do about Google Analytics, what a privacy policy must contain and who you need a data processing agreement with.

Digital accessibility for websites and online stores: WCAG 2.2, the European Accessibility Act and Polish law

Who the Polish Accessibility Act covers from 28 June 2025, what WCAG 2.2 requires in practice, and how to test and fix a site before a customer or a regulator does it for you

Since 28 June 2025, online stores and websites through which a consumer can start entering into a contract must meet accessibility requirements. Who the law covers, what WCAG 2.2 requires and how to test your site without guesswork.

Business hosting: shared, VPS, dedicated server, cloud or PaaS

Cost, performance, who administers the server and where the data lives across five hosting models, with a table of who is responsible for what

Choosing hosting is less about specs and more about deciding who will administer the server. We compare shared hosting, VPS, dedicated servers, cloud and PaaS on cost, performance, responsibility and where your data is stored.

Business website security: a checklist and a plan for when you get hacked

Updates, backups, HTTPS, security headers, forms, panel access and the first hours after a break-in, with tests you can run yourself

A small business website is usually attacked by a bot that checks for known vulnerabilities and leaked passwords, not by someone interested in the business. What to secure, how to check for yourself that it is secured, and what to do once the site has already been taken over.

WordPress vs headless CMS: which architecture to choose for a company website

Classic WordPress, a headless CMS and a static site compared on cost, security, performance and day-to-day content editing

WordPress, a headless CMS or a static site? We compare three architectures on cost over several years, security, speed and what an editor's daily work looks like, and say when each model is the wrong choice.

Core Web Vitals in practice: how we deliver 95+ in PageSpeed

Prerendering, JavaScript after the first paint, fonts without layout shift and animations in CSS. The techniques we use on our own site, with code and with their trade-offs.

A PageSpeed score and Core Web Vitals are two different numbers. We show how we measure a site before handover and which techniques keep LCP, INP and CLS in the green, including after the project has been delivered.

How much does a website cost in 2026: price ranges and what drives them

A quote broken down into hours of work, content and annual costs, so you can compare two offers for the same website

A landing page, a company website, an online store and a platform are four different purchases. We show indicative market price ranges, a sample hour-by-hour calculation and what it costs to run a website for a year.

Admin panel instead of a spreadsheet: when your business has outgrown Excel

The signs a spreadsheet is no longer enough, the situations where you are better off keeping it, and moving to a panel without losing data

How to tell that a spreadsheet costs more than it gives, what even the best-organised file cannot do, when to leave it alone and how to move the data into a panel without chaos.

Multilingual website SEO and hreflang: URL structure, translation and the mistakes that break rankings

Language or country versions, subdirectories or domains, hreflang in HTML and in the sitemap, canonical tags, localisation rather than plain translation, and a script that catches the errors

A multilingual website needs its own URL for every version, hreflang tags linking the versions together and content genuinely written in each language. We show how to choose a URL structure, how to implement hreflang with x-default, how localisation differs from translation and how to detect the typical mistakes.

Landing page vs company website: which to choose and when you need both

Five questions about your offer, your traffic source and the way customers buy that settle the choice before you pay for the wrong website

A landing page sells one thing to someone who came from an ad. A company website answers many questions for people searching on Google. We show how to choose, when a landing page does harm and how to start with one without building everything twice.

Website migration without losing Google rankings: from URL inventory to monitoring

Inventorying old URLs, a 301 redirect map, testing before the switch, changing domains in Search Console and what to watch over the following weeks

After a website rebuild, the pages that lose rankings are most often the URLs nobody added to the redirect map. We show where to get a complete list of old URLs, how to build and test 301 redirects, when to use the Change of Address tool and how to tell normal fluctuation from a mistake.

Working with a software house: how a project goes from the first message to launch

Seven stages of working with VulCode: what we do, what stays on your side and where projects most often slow down

What happens after you send the first message: the quote, onboarding in the client panel, the prototype, work on staging, testing with a buffer for fixes, code handover and monitoring after launch.

Technical SEO checklist before launch: from staging to Search Console

Indexing, robots.txt, sitemap, canonical, rendering, performance and structured data. What to check on the staging site, what on launch day and what in the first few weeks.

A new website most often loses its start in Google because of settings carried over from staging: noindex, a robots.txt block or a canonical pointing to the test domain. A technical SEO checklist with a command to verify every item.

Why we contribute to open source: what a software house gains from fixing other people's code

Fixes sent upstream to libraries, our own tools on our Git server and licences in client projects. What the company gets out of it, what the client gets and how much time it takes.

We contribute code to external open source projects and publish our own tools. Here's why a fix sent upstream to a library is cheaper than a local patch, what we don't publish and how to read a vendor's GitHub.

How to write a project brief for a software house: structure, example and common gaps

Goal, users, processes, features, data, integrations, legal requirements, budget and deadline: what a brief for a website, admin panel or app needs so that several companies quote the same project

A good brief is not a technical specification. It describes the problem, users, processes, data, integrations and constraints so that several vendors quote the same project. A structure to copy, an example and a list of common gaps.

Your own online store vs Allegro: which pays off and when to sell on both

Commissions, customer acquisition cost, buyer data and dependence on the platform's rules, worked out on a single example

Allegro brings traffic from day one and takes a commission on every order. Your own store has to win its traffic, but the customer stays with you. We work out the same product in both channels and show when each one wins.

How to read a software development quote and what to watch out for

Scope, billing model, payment schedule, rights to the code and costs outside the offer: what to check in a software house quote before you compare the figures

Two quotes for the same project are often quotes for two different projects. How to check the scope, the billing model, the rights to the code and the costs you cannot see in the offer before you pick the cheapest one.

Fixed price vs time and materials: how to choose a billing model for an IT project

A fixed price, paying for time worked, hybrid models and retainers: who carries the risk, when each model works and which contract clauses protect both sides

A fixed price shifts the risk of a bad estimate onto the contractor, time and materials onto the client, but neither model is cheaper by definition. When to choose which, how hybrid models and retainers work and what to put in the contract.

PWA vs native app: what to choose in 2026 and what a PWA still cannot do

Phone features, notifications on iPhone, app store costs and yearly requirements, laid out so that the decision follows from the feature list, not from fashion

A PWA runs from a link, updates instantly and pays no commission to the app stores. An app from a store gets Bluetooth, background work and widgets. We show what a PWA can do in 2026 on Android and iPhone, what it costs to get into the stores and when each option is the right one.

How to choose a software house: questions, red flags and the contract

Registers, portfolio, references, the first conversation and the code ownership clauses without which a contract does not protect the client

How to choose a software house when you do not know code: what to check in registers and in the portfolio, how to talk to references, which questions to ask before signing and what not to give up in the contract.

Website maintenance after launch: monitoring, fixes and upkeep for sites and apps

What only shows up under real traffic, what is worth monitoring, how to report bugs, when to deploy fixes and what the documentation needs so another team can take the project over.

Launch day is the start of the period in which a project meets real users. We describe what to watch then, how the buffer of 15% of project time for fixes works and what your options are once free monitoring ends.