I run Keystone Systems, a software studio based in the Netherlands. I take your project from the first requirements through design, development, testing and launch, with continued support agreed around your needs.
You can bring me a new idea, an existing product or a business process you want to improve. I lead the work and remain your main contact, bringing in specialists where the project needs them.
Websites, apps and software for your business
Based in the Netherlands. Dutch and English. 9+ years of software-development experience.
Services
Websites and web applications
Give customers a clear way to find information, enquire, book, buy or use your service online.
I plan and build business websites, online stores, customer portals and web applications, including the systems they connect to.
Mobile applications
Build an app for iOS and Android or continue developing a product you already have.
I manage the work across the user experience, app features, backend connections, testing and release preparation.
Business software
Make daily work easier to manage.
I build internal tools, dashboards and integrations for tasks such as handling requests, tracking progress, reporting and moving information between systems.
Book a free 20-minute introduction
Describe what you need, what already exists and any timing or budget constraints. We can discuss your project in Dutch or English and agree a useful next step.
You can hire me for a complete build, a defined improvement, a review or continued development.
Send a project enquiry or choose a time for an introduction.
Pick a time below
Based in the Netherlands. Check the calendar for available times and your local timezone.
Direct project leadership
I am Mostafa, founder of Keystone Systems. I have 9+ years of software-development experience and work with founders and businesses on websites, mobile apps and business software.
One point of contact for the complete project
You work directly with me from the first discussion through delivery. I help define the requirements, explain technical choices and coordinate the people involved.
Before development starts, we agree the deliverables, price, review points and responsibilities. When a request changes the scope, I explain its effect on the cost and schedule before asking you to approve it.
Quality that is part of delivery
I plan the relevant design, accessibility, privacy and testing work alongside the features. The scope identifies the checks included and the results you receive.
Handover includes the agreed source, assets, account access and operating instructions. We define defect correction, maintenance and further development before handover.
Client feedback
“Well what can I say other than Mostafa was a god send. I posted my project not realizing how much work was actually involved to get it accepted to the app store. There was a lot of stuff I didn’t know and Mostafa was unbelievably patient with me, he went above and beyond in walking me through everything step by step. I had a few mistakes which were correctly quickly. I honestly couldn’t of asked for better service, I will definitely be using Mostafa for future work 10/10.”
“Very diligent individual and focuses on the client needs and satisfaction. I like how he asks questions to understand the needs and delivered the product. he keeps a cool mind and completes the task. I will definitely work with Mostafa again.”
“Delivered the project lightning fast without any issues. Very satisfactory”
“Very fast and reliable, thank you”
“He is A+++ in iOS App development. More work on the way, so this should explain”
“Awesome I recommend him 100% will give him other project he is expert in his job”
“Mostafa is very professional and very easy to work with. I will hire him for my new project for sure.”
Tell me what you want to build or improve
Share your goal, what already exists and where you need help. You can ask about a new website, an app, business software or continued work on an existing product.
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