Website Design & Hosting
I create responsive, secure, and high-performing websites for your business that reflect your brand and attract customers.
- Responsive design for all devices
- SEO-optimized pages
- Secure hosting & SSL
IT services in Berlin
The IT department for Berlin businesses that don't have one.
Workstations, network, security, website and AI: I take care of all of it. One contact, a reply within 24 hours.
5.0 on Google10 reviews
Projects for: Anwaltskanzlei Korff, AST Teltow, Haus Phönix, BSU-Holding, Lindner Elektrotechnik, Growth Partners, Lotsennetzwerk Berlin, jahdara
IT solutions that keep your business running
Web Apps & Process Optimisation
When spreadsheets, email chains and paper notes reach their limits, I build a web app that mirrors your actual workflow – in the browser, on any device, with nothing to install.
- Analysis and digitalisation of your workflows
- Custom web apps instead of off-the-shelf software
- Forms, dashboards and reports at the push of a button
Local AI & RAG Systems
AI that works on your own documents and stays in-house: document search with source citations, automated quote and text drafts – running locally on your hardware or on EU servers, GDPR-compliant and without company knowledge flowing to an AI provider.
- RAG systems: answers from your documents – with sources
- Local AI models on your own hardware or EU servers
- Automated drafts for quotes, emails and reports
IT Support for SMEs
Reliable IT support for your company, including troubleshooting, hardware & software management, and user assistance.
- Remote and on-site support
- Software installation & updates
- Hardware setup and repair
Network & Infrastructure
I design and implement secure and scalable networks, including wired and wireless setups, VPNs, and server architecture.
- Network planning & deployment
- Secure Wi-Fi & LAN setup
- VPN & remote access solutions
Cybersecurity
Protect your business with comprehensive cybersecurity services including risk assessment, threat prevention, and compliance.
- Security audits & risk assessment
- Firewall and antivirus setup
- Employee training on cyber threats
Free checks for your business
Two minutes, no account, instant results. Get the detailed report by email if you like.
How secure is your IT?
10 questions on backups, updates, passwords and incident planning. With concrete next steps.
Start the checkAbout 2 minutes
Projects that speak for themselves.
Real clients, real results – from law firms and car workshops to a GDPR-compliant AI system.
Website · Law firm
Anwaltskanzlei Korff
A trustworthy presence for criminal law and defence in Berlin: clear structure, a prominent emergency contact and confidence from the very first click.
Concept & buildLocal SEOGDPR
View website
IT infrastructure · Social sector
Entra ID & domain for Haus Phönix
Microsoft Entra ID as the central identity for the non-profit organisation: new domain set up, eight computers for all offices configured and joined to the domain – one login for everything, centrally managed, ready to grow.
Microsoft Entra ID8 workstations set upCentral management
Microsoft Entra IDCentral identity · domain
0
computers set up
0
login for everything
0 %
offices equipped
Web app · Social sector
Survey tool for Haus Phönix
Digital survey tool for the non-profit housing project's drug prevention work: anonymous, low-threshold and evaluated at the push of a button.
Custom buildAnonymous participationEvaluation & export
View website
umfrage-tool: markus@lindner-tech
AI system · Holding
GDPR-compliant RAG system for BSU-Holding
Company-owned AI that searches documents and drafts quotes from them: contracts, service specifications and past quotes are indexed in-house, every answer cites its source – no company knowledge leaves the business.
RAG & document searchAutomated quote generationGDPR · runs locally
About Markus Lindner
My Background
I'm Markus Lindner, founder of Lindner Tech, an IT specialist from Berlin and certified application developer (IHK Berlin). I combine system administration with software development: Windows servers, networks and Microsoft Azure on one side, modern websites built with TypeScript and React on the other. I grew up bilingual in German and Polish, speak fluent English and work with clients across many industries every day.
My Experience
I spent five years at Siemens AG in Berlin working hands-on with IT infrastructure, ELK-stack monitoring and automation using PowerShell and Python. Today I administer networks, servers and Microsoft 365 professionally and deliver freelance projects for small and medium-sized businesses: complete web platforms with Next.js and React, IT infrastructures for law firms and real estate agencies, cloud systems, data recovery and network installations – for example for Bullet Shop Berlin.
My Approach
Every project starts with a thorough analysis of your IT needs to identify risks and opportunities systematically. Based on that, I develop scalable solutions such as secure networks, professional websites and modern security measures – and implement them efficiently, focused on reliability and long-term stability. After go-live I stay on board with continuous support, consulting and optimization.
Why Choose Me
I work hands-on and solution-oriented. With recognized certifications in cybersecurity and data privacy, experience from both enterprise and small business environments, and a completed IHK vocational degree, I deliver secure, reliable and growth-driven IT solutions tailored to SMEs. Technical expertise meets clear client focus – so your IT doesn't just run, it runs sustainably, securely and efficiently.Degrees & Certifications
IT Specialist (IHK Berlin)Application development, certified 2026
Python 3 – Top 1%CodinGame Certification
C++ – Top 2%CodinGame Certification
Siemens CybersecurityData Privacy, Network Hardening, IT Regulation
Elasticsearch & ELK StackMonitoring practice from 5 years at Siemens AG
Microsoft Azure & 365VNets, Active Directory, daily administration
Free consultation
Tell me briefly what it's about, or give me a call. I'll get back to you within 24 hours.
Business clients only: companies, self-employed professionals and organisations.
Practical knowledge for SMEs
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