I take the spreadsheets and manual routines your business runs on and turn them into proper web apps, dashboards and automated workflows you can actually trust.
I reverse engineer Excel, build it into secure software, and take care of the development, hosting and AI around it.
A spreadsheet that has quietly become business-critical over the years is a black box. One person knows how it really works, the data is sitting there unprotected, and a single wrong edit can bring the whole thing down.
file often decides pricing, margins and deliveries, with no documentation, access control or backup logic.
One person understands the logic
key person riskFormulas break silently
silent failureNo access control or audit trail
no governanceSensitive data sits unprotected
security riskPrices and numbers drift out of sync
inconsistent outputAI cannot help on an undocumented, insecure process
blocked by chaosI dig into the actual logic, make it secure, and hand back a system that runs safely in everyday use. That is what reverse engineering and a proper rebuild come down to.
I deconstruct complex spreadsheets cell by cell and rebuild them as secure systems with encryption, access control and validation. Apps are one possible output, not the whole job.
Manual processes become AI driven workflows that create real operational value, with people kept in the loop where it matters.
Threat modeling, MFA, role based access and audit ready logging, so your systems stay trustworthy and compliant.
An optional supplement to a finished secure system. I build, host and maintain the website and dashboards that sit on top. An add-on, never the main offering.
I do not only build software. When it makes sense, I also build the apps and interfaces that sit on top of the secure system. Sometimes an app is part of the answer, but it is rarely the whole job.
Final pricing depends on spreadsheet complexity, security requirements, integrations, number of user roles, data sensitivity, validation needs and business criticality. Larger configurators, production systems and enterprise rebuilds are quoted after assessment.
All engagements start with a free intro conversation. Full rebuilds require scope assessment before final pricing.
Different shapes, same idea: the hidden logic becomes a tool your team can actually use.
Rule based product setups with live pricing and validation.
Quoting tools that replace fragile Excel quotes.
Real time overview of margins, pricing logic and scenarios.
Assistants trained on your own processes and data.
Internal tools that gather sales, operations and data in one place.
Reliable hosting, CI and CD, and monitoring.
Logic and processes documented and searchable.
AI environments tailored to your domain and terminology.
This is the same process I run on real projects, shown from start to finish: the hidden formulas in a spreadsheet are mapped out, turned into a clean input model, rebuilt as a secure engine, and finally given a dashboard your team can trust.
Undocumented cells, nested formulas and hidden logic.
Every formula and reference mapped, including the hidden ones.
1,240 edgesInputs typed, validated and de-duplicated into one clean model.
Business rules rebuilt with encryption, access control and validation.
A secure, role based interface your whole team can rely on.
It is the same business logic, just rebuilt so it is documented, secure and tested. Here is what actually changes for your team.
An anonymized case that shows how a fragile spreadsheet ends up as a documented, secure system the business can rely on.
Legacy Excel configurator
47 sheets, undocumented
Dependency graph
1,240 formula edges
Canonical input model
62 typed inputs
Validated calculation engine
test suite, parity ok
Secure admin dashboard
live, role based
Complex spreadsheet formulas, dependencies and exceptions are translated into documented system logic.
Role-based access, audit-ready structure and secure data handling replace uncontrolled spreadsheet sharing.
The new system is validated against the original logic, so the business can trust the output.
Good application security keeps systems up and saves you money, because catching a problem early is far cheaper than cleaning up after it. Every Excel rebuild I do comes with encryption, access control, logging and sensible DevOps.
Static and dynamic testing finds vulnerabilities before they reach production.
Strong sign in keeps accounts safe even if a password leaks.
Each person sees only the data and actions their role allows.
Sensitive data stays protected on disk and across the network.
Security sits in every step of the pipeline instead of being tacked on at the end. You get safer releases and a clear trail for any audit.
Issues are caught in the pipeline before your users ever see them.
Fixing a flaw early is far cheaper than recovering from a breach.
Logging and access control make audits straightforward.
Customers and management can rely on a system they know is secure.
A structured, transparent process. You know exactly what happens at each step, that the output matches your original logic, and that it is secured along the way.
I review the file, identify critical cells, inputs, outputs and where the risk sits.
Every formula and dependency is mapped into a dependency graph, including the hidden ones.
The logic is translated into clear, documented business rules that can be tested.
The rules are rebuilt as a secure web app, calculation engine or AI workflow.
The new system is validated against the original calculations and hardened with security controls.
I review the file, identify critical cells, inputs, outputs and where the risk sits.
Every formula and dependency is mapped into a dependency graph, including the hidden ones.
The logic is translated into clear, documented business rules that can be tested.
The rules are rebuilt as a secure web app, calculation engine or AI workflow.
The new system is validated against the original calculations and hardened with security controls.
Anonymized feedback from real engagements. Names are withheld by agreement, the work speaks for itself.
Our pricing logic lived in one enormous spreadsheet only one person fully understood. It is now a secure system the whole team uses, with zero calculation deviations after validation.
We finally have access control and an audit trail on the numbers that run the business. The rebuild paid for itself the first time it caught an error before it reached a customer.
Straight, technical and honest. No buzzword AI demo, just a working system in production that our auditors were happy with.
These are three different kinds of work, not a cheap-to-expensive ladder. The audit tells you where the risk is, the rebuild turns your critical logic into secure software, and the AI engine adds controlled automation and knowledge tools on top.
Diagnostic review of risk, hidden logic, security exposure and rebuild potential. Best before committing to a larger build.
Full technical rebuild of critical spreadsheet logic, pricing rules, configurators or operational workflows into secure production software.
Controlled AI workflows, internal assistants and company-specific knowledge systems built around existing processes.
Understanding risk, hidden logic and rebuild potential before committing.
Critical spreadsheets, pricing tools, configurators and operational logic that must become secure software.
Internal AI workflows, assistants, knowledge bases and controlled automation.
Diagnostic review of risk, hidden logic, security exposure and rebuild potential. Best before committing to a larger build.
Understanding risk, hidden logic and rebuild potential before committing.
Full technical rebuild of critical spreadsheet logic, pricing rules, configurators or operational workflows into secure production software.
Critical spreadsheets, pricing tools, configurators and operational logic that must become secure software.
Controlled AI workflows, internal assistants and company-specific knowledge systems built around existing processes.
Internal AI workflows, assistants, knowledge bases and controlled automation.
Final pricing depends on spreadsheet complexity, security requirements, integrations, number of user roles, data sensitivity, validation needs and business criticality. Larger configurators, production systems and enterprise rebuilds are quoted after assessment.
All engagements start with a free intro conversation. Full rebuilds require scope assessment before final pricing.
Once a system is live it still needs looking after: updates, monitoring, the odd small change and general technical care. Pick the level of support that fits how important the system is to you.
For websites, landing pages and smaller web platforms that need secure updates, monitoring and light ongoing care.
For dashboards, admin systems, backend flows and custom web apps that need monthly technical care and improvements.
For business-critical systems, AI workflows, configurators, lead pipelines and secure platforms where downtime or errors matter.
A simple website only needs a light touch. Dashboards, AI workflows and business-critical systems need closer monitoring, quicker response times and steady improvement over time. We settle on the right level once I have seen the system.
As a rule of thumb, larger systems often reserve an annual maintenance budget equal to 15-30% of the initial build cost, depending on complexity and SLA.
These are 'from' prices. More complex systems, custom SLAs, high-traffic platforms and business-critical operations are scoped individually.
I work across AI, reverse engineering, system design, secure web apps, server operations and the practical business side of things. I am not interested in flashy AI demos. I care about building secure systems that hold up in everyday use.
If your question is not here, write to me and you will get a straight answer.
Yes. You own the full source code, the documentation and the rebuilt system. There is no lock-in and no hidden licensing on your own business logic.
Yes. Everything is handled confidentially and I am happy to sign an NDA before you share any files or data. The engineering case on this site is fully anonymized.
Every rebuild is validated against your original calculations with a parity test suite. You see the results, and we do not go live until the numbers match.
Pretty secure. Encryption at rest and in transit, multi-factor login, role-based access and audit-ready logging are part of the build from the start, with DevSecOps practices across the pipeline.
A Secure System Audit is quick. A full rebuild depends on complexity, but you get a clear scope, timeline and fixed expectations after the assessment, before any large commitment.
I am EU based and build with GDPR in mind: data minimization, access control and clear handling. Your data is never used to train external models without your explicit agreement.
Yes. I can host, monitor and maintain the system, or hand it over with full documentation so your own team can run it.
Start with the free intro conversation. We look at your situation together and you get a concrete recommendation, with no obligation.
A practical checklist to spot key person risk, silent errors, security gaps and rebuild potential in your most critical spreadsheets. Sent straight to your inbox.
Let us take a look at it together. A Secure System Audit gives you a clear picture of the risk, where the gaps are and what to do next.
Tell me briefly about your situation, whether it is a spreadsheet, configurator, pricing, security concern or workflow. You will hear back from me with a concrete next step.
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