Many sources,one truth.

I connect your data sources into one warehouse and build dashboards and analyses your team trusts. Based in Cologne, for small and mid-sized businesses.

Many sources, one number

I pick up your data where it lives today. I clean it, bring it together in one central warehouse and define what terms like revenue or customer mean. Those definitions then apply everywhere. The dashboards build on them.

Rule of thumb: if you don't know where to start, start with the Data Audit. 2 to 3 sources usually means Data Foundation, 4 or more means Data Platform. If data should also flow between tools, it is Connected Stack.

Sources

Shop, ad accounts, CRM, accounting exports, spreadsheets, line-of-business software. Connected via API or export, loaded automatically.
Warehouse

One central store on your own cloud account. The data is checked, cleaned and combined in a documented model.
Dashboards and analyses

A few pages with the metrics you actually steer by. In Power BI or Looker Studio, with definitions anyone can follow. As an extension, forecasts with machine learning.

Services

Five building blocks with a clearly defined scope: an assessment, three core packages, ongoing support and optional extensions. Prices on request, fixed in the written offer.

Assessment

Data Audit & Roadmap

Before any project. You know your data is a problem. You don't know where to start.

Included: Review of up to 10 data sources, tools and reports
Up to 5 conversations with the people who work with the numbers today
Data quality spot checks in the 3 most important sources
Written roadmap with prioritised steps and a package recommendation
90-minute wrap-up meeting
Not included: Implementation, connectors or dashboards

If you commission an implementation package within 3 months, I credit 50 % of the audit price towards it.

Enquire: Data Audit & Roadmap

Core packages

Three packages for the build. Which one fits depends on your sources and goals.

Services: Data Foundation, Data Platform, Connected Stack
	Data Foundation	Data Platform	Connected Stack
Who it is for	Companies with a few sources that want a reliable base of metrics for the first time.	Companies with many sources or several departments that need their own analyses.	Companies whose tools don't talk to each other. Data is copied across by hand today.
Included	Connection of 2 to 3 sources Central warehouse on your cloud account Data model for your core metrics, with definitions One dashboard with up to 5 report pages Daily automatic refresh Documentation and handover workshop	Connection of 4 to 8 sources Automatic, monitored loads with alerts on failure Data quality tests in the model Dashboards for up to 3 areas, e.g. sales, marketing and finance, with access rules Documentation and handover workshop	Analysis of the existing processes between your tools Integrations for up to 3 data flows, e.g. shop to CRM to accounting Error handling and alerts Documentation and handover workshop
Not included	Real-time data Data flows between tools Licences and cloud costs	Machine learning and AI (as an extension) Licences and cloud costs	Building new line-of-business software Licences for integration platforms
	Enquire	Enquire	Enquire

Data Foundation

Who it is for: Companies with a few sources that want a reliable base of metrics for the first time.
Included: Connection of 2 to 3 sources
Central warehouse on your cloud account
Data model for your core metrics, with definitions
One dashboard with up to 5 report pages
Daily automatic refresh
Documentation and handover workshop
Not included: Real-time data
Data flows between tools
Licences and cloud costs

Enquire: Data Foundation

Data Platform

Who it is for: Companies with many sources or several departments that need their own analyses.
Included: Connection of 4 to 8 sources
Automatic, monitored loads with alerts on failure
Data quality tests in the model
Dashboards for up to 3 areas, e.g. sales, marketing and finance, with access rules
Documentation and handover workshop
Not included: Machine learning and AI (as an extension)
Licences and cloud costs

Enquire: Data Platform

Connected Stack

Who it is for: Companies whose tools don't talk to each other. Data is copied across by hand today.
Included: Analysis of the existing processes between your tools
Integrations for up to 3 data flows, e.g. shop to CRM to accounting
Error handling and alerts
Documentation and handover workshop
Not included: Building new line-of-business software
Licences for integration platforms

Enquire: Connected Stack

Ongoing support

Operations & Development

After handover: someone keeps an eye on your setup.

Monitoring of loads, adjustments when sources change, small extensions and new analyses, a fixed point of contact.

Up to 20 hours per monthWe set the volume based on your needs.Minimum term 6 months, then renews for 3 months at a time. Up to 5 unused hours carry over to the next month.

Enquire about support

Optional extensions

Analytics, machine learning and AI

Once the foundation is in place, the same data can power forecasts and automation. Building on Data Foundation or Data Platform.

Forecasts Sales, revenue or demand for the coming weeks, with uncertainty you can follow.
Customer segments Groups with similar behaviour and early signs of customers about to churn.
Reading documents with AI Capture and classify invoices, delivery notes or emails automatically.
Questions to your own data Analyses in plain language, based on your warehouse and its definitions.

Whether a model is worth the effort, I check on your data first. Sometimes a good analysis is enough. Models run on your accounts. Data is not passed to third parties unless you explicitly choose an AI service under a data processing agreement.

Your project doesn't fit a package?

I am open to any kind of data project. Tell me what you have in mind. I will tell you honestly whether and how I can help.

Enquire about a project

What to know beforehand

Prices: On request. After the intro call you receive a written offer with a binding price for the agreed scope.
Possible extra costs: Licences (e.g. Power BI Pro), cloud and warehouse operation and paid APIs are paid by you directly to the provider. I list them in the offer upfront.
Acceptance: At the end of each package you check the result against the agreed specification. Changes to the scope are agreed in writing beforehand.
Cancellation: Up to 30 days before the project start, 20 % of the price, after that 40 %. After the start, work done plus 50 % of the remainder. One free postponement is possible.

All terms and conditions

Process Four steps from the intro call to handover.

First, we talk.

In the intro call you tell me what you want to do with your data. I say openly whether I can help and with which package.
Then the scope is fixed.

You receive a written offer with a binding price, deliverables, exclusions and a timeline.
Then I build.

We check in briefly and regularly. You see progress along the way, not just the end result.
In the end, it is all yours.

Handover with documentation and a workshop. Code, warehouse and dashboards run on your accounts.

In practice Project example: a data stack for a creative agency

Built in a project during my master's programme, together with an agency from Cologne. I use the same building blocks in any industry, adapted to your sources and goals.

Industry: Creative and marketing agency
Size: ~25 employees
Sources: 13+ source systems
Tools: BigQuery, Airbyte, Data Studio
Duration: ~4 months

Starting point

Hours, budgets, invoices and campaign data were spread across more than 13 tools. Whether a client project had paid off only showed in a spreadsheet after the project ended, put together by hand every month.

What was built

Airbyte loads the data from the source systems into BigQuery automatically. A data model brings hours, budgets and invoices together per project, with fixed definitions for utilisation and contribution margin. Dashboards in Data Studio for management and project leads build on it.

Result

Budget use and utilisation per project are visible continuously instead of after the fact. The monthly manual report is no longer needed. Everyone works with the same definitions.

About me David Sättler, data engineer from Cologne.

Portrait of David Sättler: smiling, wearing glasses and a light blue shirt against a light grey background.

I am David Sättler, a data engineer in Cologne. I build data foundations for companies without their own data team.

I am studying for a master's degree in Business Analytics & Econometrics. Professionally, I work in Data Engineering & Integration, where I gained experience with data pipelines, interfaces between systems and data models. I also bring experience in data analytics and data science.

I work alone. So you always talk to the person who builds. If a project is not a good fit for me, I tell you in the intro call.

Based in: Cologne, Germany
For: SMBs with 5 to 50 employees
Region: On site in Cologne and NRW, across Germany by arrangement, remote across Germany, Austria and Switzerland
Focus: Data engineering, warehouse, data analytics, machine learning

FAQ Cost, duration, data protection, tools and more.

What does it cost?

It depends on the scope: how many sources, what state the data is in, which analyses you need. After the intro call you receive a written offer with a binding price. As a small business under § 19 of the German VAT Act, I do not charge VAT. Licences and cloud costs are paid by you directly to the providers. I name them upfront.

How long does a project take?

That also depends on the scope. We set the timeline together in the offer. How fast it goes also depends on when access to your tools is in place and who on your side is available for questions.

Do you also offer machine learning and AI?

Yes, as an extension. Forecasts, customer segments or AI for documents are only as good as the data underneath. That is why the foundation comes first. After that I tell you honestly where a model helps and where a good analysis is enough.

How do you handle data protection and GDPR?

Your data stays on your own accounts, in an EU region where possible. I only get the access I need for the project and hand it back at the end. If I process personal data on your behalf, we sign a data processing agreement under Art. 28 GDPR first.

Which tools do you work with?

That depends on the project. I adapt to your existing stack and get up to speed with new tools, whether AWS, Azure or Google Cloud, Airbyte, dbt, Power BI or Looker Studio. If nothing is in place yet, I suggest a lean, affordable setup. For machine learning I use Python with common libraries.

Who owns the result?

You do. Warehouse, code and dashboards run on your accounts. You get the documentation and the handover. You are not tied to me afterwards.

What happens after handover?

You can carry on by yourself. Or you book Operations & Development: up to 20 hours per month as needed for monitoring, adjustments and new analyses, with a minimum term of 6 months.

What if we have to cancel a project?

Up to 30 days before the start I charge 20 % of the price, after that 40 %. After the start you pay for the work done plus 50 % of the remainder. One postponement is free. The details are in the terms and conditions.

We are very small. Is it worth it?

We find that out in the Data Audit. Sometimes the honest recommendation is to stay with a well-structured spreadsheet. Then I tell you so, instead of selling you a warehouse you don't need.

Let’s talk about your data.

Book a call directly Send an email: hallo@rheinstack.de

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Based in Cologne. On site in NRW, across Germany by arrangement, remote across Germany, Austria and Switzerland.