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Your process runs on a spreadsheet, an ageing application or a patchwork of systems that no longer keeps up. We turn it into custom software your people use — without a years-long development project. Every system we have delivered has gone into use.
One of our systems has served around 7,500 users worldwide since 2018 — on the same database, without a rebuild.
Since 2026, ExcelSpecialist has been a trading name of Jazetti. We deliver Excel and VBA solutions under that established name.
Web applications, Excel and Google Sheets solutions, integrations between existing systems.
A stalled software project, or an application whose builder has left. We establish what exists, what works and what is missing, then develop it further responsibly. With AI support, considerably faster than before.
Connecting data sources and turning them into current overviews, including financial ones.
Business-critical software has to keep working. We maintain and develop it further, under an arrangement that fits what your system needs.
That is part of the agreement. If your application should run in your own environment, or your situation calls for another location, we arrange it that way.
An international technology company plans its projects in euros and person-hours, per project, per department and per period. The people who enter them work across every time zone: there is no quiet moment.
We built a resource management system in which around 7,500 users work worldwide. They work in Excel, but the file stores nothing: all data lives in one central database that allows one edit per record at a time. Anyone who wants to change something a colleague is working on sees straight away who that is.
Delivered in 2018 and still in use today, on the same database, without a rebuild.
We don't name the client. The full case, with a diagram, is on excelspecialist.nl. Facing something similar? Get in touch.
Business-critical software that gets used, grows with you and keeps running. These are the questions customers ask us before they start, with our answers.
We build with your users and train them to work with it. The real test is adoption, not delivery. One of our systems is used by about 7,500 people worldwide. The phone does not ring. That is the best measure we know — and yes, we are touching wood as we write it.
Then we build it, fast. We build so that your system can grow with you: start with five users and grow to ten thousand, without starting over. You pay for what you add, never for starting over.
Our longest partnership began in 2013 as a short assignment, is still running and grew to at least five projects a year. "Can it also do this?" "Yes, here it is." That is how it works.
An SLA, with agreements on support and recovery, is always part of it. The SLA sets out how you report an incident, how quickly you get a response and who takes over if your usual contact is unavailable. No black box. Your knowledge doesn't live in one head. We build from written agreements on what the software must do, with documentation and a manual. We train your own key users. On request we also train your technical staff, with a licence to maintain the system themselves. Source-code escrow (the source code held by an independent party) is arranged on request. Your data can always be exported.
Your application and data run in Europe; our own servers are in Amsterdam. On our own platform, every night an encrypted copy goes to a second country, with a different company. Every week we test that the copy can be restored. If a server is lost, your system runs again within one working day. You can see the current status of our own platform on our proof page.
When the software is ready for production, so is the documentation: a manual, a data storage plan, information for your register and about our sub-processors, and a processing agreement ready for signature. Feel free to have your own advisor review it.
Yes, and we recommend it. Nothing is put into use until it has been checked in a separate test environment. Our servers are set up and maintained through code; nobody changes anything on them by hand. Your IT advisor can request our technical overview under NDA: architecture, security, backups and continuity. Request the technical overview
Whatever your situation needs, we design with you. For example, live storage in two locations at once, or your own chat channel hosted in Europe. Or a customer portal on request: status, proof and your open requests in one place, secured with an authenticator app.
We use AI to analyse and build faster, always from written agreements on what the software should do. Our development standards, testing and a human final review determine what reaches production.
AI writes the code, the standard safeguards quality, and a person signs off on the release.
We build in rounds, not in phases: set down, build, review together - until it fits.
The framework is the instrument; the music is the solution your people use every day. Excel · Google Sheets · SharePoint · PHP · MySQL
We work AI-assisted, but always within the client's own boundaries. Where a client prescribes systems, tooling or approvals, we work inside them — on the client's own laptop or VDI. Business data does not leave that environment.
AI quickly gives an answer that is right in the general case — and misses the exception for exactly that reason. Someone who does not know the field cannot see the difference and takes the answer as it stands. Our value is in recognising the exception on which a general answer breaks down.
One question, six rules. Change the situation and see what happens.
The situation
The answer
Yes, if release by finance · customer agreement
6 rules checked — 2 need action
Six rules, one answer. Your process has hundreds — and your people want one answer out of them. That is the work.
You speak to the people doing the work — the person building your application is also your point of contact. For specialist components we work with trusted specialists from our network.
We come from the field: logistics, supply chain, finance.
We deliver Excel and VBA applications under our trading name ExcelSpecialist: founded by Ruud Coopmans in 1996, with more than six hundred clients since. Ruud remains available for advice.
Custom work only succeeds when both sides trust each other and want the same result.
Within one working day, Dennis or Margo replies personally.
A first conversation, free and without obligation. We want to understand your process; you want to find out whether it clicks. If it doesn't, we'll say so.
If it fits, you receive a written proposal: what we'll build, in which rounds, and what you can expect from us.
You can reach us by email or phone: info@jazetti.com · +31 6 10 100 843
Prefer to email or call? info@jazetti.com · +31 6 10 100 843
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Prefer to email or call? info@jazetti.com · +31 6 10 100 843
