Single Sign-On
One login for all modules
Mein.BauKastl
Perfect for founders, sole proprietors and medium-sized businesses
Mein.BauKastl is the central hub for all tools of the BauKastl platform — invoicing software, website builder, everything under one roof. One login, all modules, German servers, no trackers.
And now brand new, the Termin.BauKastl
Everything combinable together.
What is Mein.BauKastl?
The simple answer: Your personal cockpit. You log in once and see all the modules you use — whether invoices, website, appointment scheduler, or future extensions. No second password, no second system, no back and forth.
Module Overview
See what's active and what can be added
Own Subdomain
Automatically set up per module
Centralized Password Reset
Change it once, applies everywhere
GDPR-compliant
Hosted in Germany, no external trackers
Free of Charge
Included in the price of the modules
Why BauKastl exists at all
Born out of necessity
I wanted to start a side business — and found myself where many do: amid tables of "software comparisons", a list of SaaS tools each with their own logins, their own prices, their own privacy policies, and the uneasy feeling that the standard solutions were either too big, too expensive, too American, or too limited.
What I needed was simple: write invoices, GoBD-compliant. A website that looks good on every device. Data in Germany. No cookie-banner acrobatics. No hidden limits. And ideally all of it under one roof, so I wouldn't have to learn a new tool for every little thing.
Since this combination didn't exist anywhere at fair prices, I started building it myself — first for me, then with the ambition that it should work for others too. With the same software quality that I demand of myself in my main profession as an IT service provider.
Martin Weinzierl · Weinzierl IT & Software Solutions · Passau
The Modules
Currently, there are three modules that can be activated via Mein.BauKastl. All three are self-contained and can be used individually or together.
Rechnungs.BauKastl
from €9.90/month · modular and expandable
GoBD-compliant invoices & quotes
XRechnung 3.0 + ZUGFeRD 2.1 (PDF/A-3)
Income statement (EÜR), VAT advance return, DATEV export
SEPA direct debit module (pain.008)
Bank CSV import with auto-match
GDPR data export & anonymization
Web.BauKastl
from €9.90/month · 4 packages
Drag & drop editor for pages and blocks
Your own domain
Multilingualism as a language pack add-on
AI text suggestions in the admin panel
Basic SEO settings + sitemap
Cookie banner without trackers
Termin.BauKastl
For just €4.90/month
For businesses with one or more bookable resources.
Unlimited resource calendars
Travel time buffer + distance-based travel fee
Online booking block (with Web.BauKastl booked)
Appointment → invoice/quote (with Rechnungs.BauKastl booked)
Calendar sync (iCal + CalDAV)
Employee access at no extra cost
Your own subdomain {ihrname}.termin.baukastl.de
Hosting and backup in Germany
Planned Modules: The platform is built so that additional modules can dock on effortlessly. On the wish list is, among others, Doku.BauKastl (document archive with full-text search). If you have a need, get in touch — your wish could become the next module.
What BauKastl stands for
Hosting in Germany
Hetzner Falkenstein/Nuremberg, ISO 27001 certified. Your data never leaves the EU.
Personal
A real person, not a call center. You know who's on the other end — and I know who you are.
No lock-in
Data export with one click. If it doesn't fit, you take everything with you. I keep you through quality, not contracts
Expandable
Built modularly. Whatever's missing today can be added tomorrow — without you having to switch systems.
Why not just use Lexware or Wix?
The established providers are good — but they're made for others. Lexware targets tax advisors, Wix sells photo templates for artists, Stripe-based tools are optimized for US scale. If you're a small German freelancer or small business owner who needs a pragmatic, complete, and fair toolkit, you fall outside the standard plans — either you pay for features you never use, or you hit limits you didn't expect.
BauKastl is built exactly for this gap: enough tools for the next ten years, without having to fight your way through enterprise features you don't even need.
How to get started
Create an account at mein.baukastl.de — just email + password, no payment details.
Choose a module — invoices, website, or both.
Within a few minutes you'll get your personal subdomains and login details.
Get started — or ask a question, I'll answer personally.
„I build this platform with the standard that I would use it every day — and I do. If something doesn't work, I'm the first to suffer from it."
Martin Weinzierl · Founder, Developer & Support all in one
Weinzierl IT- & Softwaresolutions · Passau
