New
App developer and IT consultant
TheJumpingFox.nl
I'm Pim Uijttewaal, an app developer and IT consultant from Nieuwveen in the Netherlands. After more than thirty years in IT at international companies, I now build carefully crafted apps for Mac, iPhone and iPad, and lightning-fast custom websites. The Uijttewaal family fox is my signature.
Software
Coming soon!
Declaruur
Clock in, bill out
Coming soon: a must for every freelancer in the Netherlands. A no-nonsense app for your hours, expenses and mileage per client, with a neat timesheet in a few taps. Your 1,225-hour criterion and your independence status always in view.
Works on your iPhone, iPad and Mac, synced in real time through your own iCloud
Free for 15 days, then a one-off € 19.95 for lifetime use
Direct contact with the developer for feedback and suggestions
iPhone · iPad · Mac · coming soon to the App Store
Everything about Declaruur at declaruur.nl
iSee all features
Vossenpost
Now on the App Store
A lightweight mail notifier in your menu bar. Vossenpost keeps an eye on your IMAP mailboxes and lets you know with a barking fox when new mail arrives. Its English name is Foxifier.
macOS · free with one account, Vossenpost Pro for multiple accounts
Download on the Mac App Store
The Jumping Fox
Free
A playful screensaver: the Uijttewaal fox jumps across your screen, with the time and date at a glance. For macOS and Windows.
macOS 14.6+ · Windows 10+
Go to the download
The downloads will soon move to this site. Until then you can find them at uijttewaal.info .
Why TheJumpingFox?
On the roof of the L.P. Uijttewaal canning factory on the Kattenbrug there once stood, in huge letters, “Jumping Fox Gherkins All Over The World” . The text had to be readable from planes approaching Schiphol from the south: clever, free advertising. The factory's fox is the same fox that now jumps through this software.
In Ter Aar, where I was born, you come across the fox everywhere: in the old municipal coat of arms and in several street names. Curious where that fox comes from ?
View the original photo of the factory
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Jumping Fox Gherkins All Over The World
I had AI turn the building around by 180 degrees. View the original photo
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Declaruur coming soon
The time-tracking app for Dutch freelancers. Keep track of your hours, expenses and mileage per client and create a neat timesheet in a few taps, ready to email or print.
Always and everywhere in sync
Enter hours on the building site with your iPhone, have them signed off on your iPad and create the timesheet on your Mac. Everything syncs automatically through your own iCloud.
Pay once, no subscription
Try it free for 15 days. After that you pay once, € 19.95 , for all your devices: iPhone, iPad and Mac. Including updates and support.
Time tracking the way you work
Start and stop a timer, from your Mac's menu bar too
Enter hours manually, with rounding and breaks
Up to 25 active clients, each with their own hourly rate
Projects and jobs per client
Mileage tracking and reminders when your hours are still empty
Expenses and receipts
Add recurring expenses with one tap
Scan receipts: the date and amount are filled in for you
Attach receipts to your timesheet
Timesheets in your own branding
With your own logo, company name and website
Any period you like, per client
Email, save as PDF or print via AirPrint
Have your client sign off digitally
Three themes for the app and your timesheets
Made for Dutch freelancers
Counter for the 1,225-hour criterion
Warning signs for false self-employment: number of clients, share of revenue and duration
VAT: 21%, 9%, reverse charge or the small business scheme (KOR)
Your data stays yours
Everything is on your own devices and in your own iCloud; we can't access it. Export everything as CSV or PDF, even years later.
Your opinion counts
Missing something or have an idea? Use the Feedback & suggestions button in the app. The developer reads everything.
Declaruur does not give tax or legal advice; the information on the hours criterion, false self-employment and VAT is indicative.
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An app, an IT challenge, or a website that really has to be fast? Tell me briefly what you're looking for and I'll see what I can do for you.
Custom apps for Apple. Your own app for iPhone, iPad or Mac, exactly the way you need it: from a smart tool for your team to a product for your customers, outside the App Store too if you prefer.
IT consultancy. Over thirty years of experience, in recent years as a technical architect in international IT environments. Interim IT, projects, data migration and integrations between systems.
Lightning-fast native websites. No WordPress and no plugin hassle, but a custom-built website that is fast, secure and easy to find.
Feel free to leave your phone number: I'll call first, with no obligation. Want to know who I am first? Read more about me . Have a question or wish about Declaruur? That's welcome too.
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New
The fox goes into business
From 1 December , this fox officially takes the plunge: that's when I start my own company.
My attention is now on Declaruur , an app that lets freelancers track their hours without a spreadsheet with seventeen tabs.
And what else? I'm open to interesting freelance assignments, from IT projects to consultancy. The more complicated the puzzle, the better: foxes are curious by nature. Feel free to get in touch.
Kind regards,Pim
To declaruur.nl ↗ OK
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The story
About the name, and about me
Background
For decades I was in permanent employment, in recent years as a technical architect in international IT environments. It was a good time, but now I'm building my own business. Small, fast and without meetings where someone wants to explain something “just briefly”.
What I'm building now
My biggest project so far is Declaruur : an app that lets freelancers track their hours simply and accurately. I also build apps exactly the way you want them: custom work for Mac, iPhone and iPad, outside the App Store too if you prefer.
Available for assignments
I'm available for freelance assignments: interim IT, IT projects, data migration, and building a complete new website. No WordPress, no Joomla, no plugin hassle and no page that first has to load JavaScript for three seconds. Just a native website, the way it should be: lightning-fast, secure and fully custom-built , like this site and the Declaruur site. Integrations with other systems are no problem. It does cost something, but you get real value in return. Interested? Get in touch.
And that name?
Why does that fox actually jump? I tell you more under Why TheJumpingFox? .
Kind regards,Pim
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Behind the scenes
A native website: how I build it
SECURELY BUILT
thoroughly tested
Pure code, no page builder
No WordPress, Joomla or page builder with dozens of plugins. Every page is written by hand, in HTML and CSS with a little PHP and JavaScript. Only what's needed is running, so there's very little that can break or leak.
Lightning-fast
No heavy frameworks and no third-party trackers. Images use a modern format and the right size. declaruur.nl scores 100 on Google PageSpeed, on mobile too.
Fully responsive
The site adapts to any screen: phone, tablet, laptop or large display, portrait or landscape. That's not a separate mobile version, but one design that moves with you. Text stays readable without zooming, buttons are big enough for a thumb and nothing falls off the screen. On many sites it's different: a design made for the computer that only just fits on a phone, with tiny text, buttons that overlap or a page that slides sideways.
Being found on Google
Hiding keywords in the page hasn't worked for years: Google ignores the “keywords” meta field completely. What counts now:
speed and stability while loading (Google measures this with Core Web Vitals);
a site that works well on mobile, because Google assesses the mobile version first;
a clear title and description for every page, so the search result is right;
a clean structure with headings, descriptive text for images and a sitemap;
for multiple languages: a separate address per language, with the right references between them;
a secure connection (HTTPS);
and above all: real, useful content.
I also set up the preview cards you see when sharing on Facebook, LinkedIn or WhatsApp for each page, with the right title and image.
Proven technologies
HTML, CSS, PHP and SQLite have been around for decades, are well documented and are used worldwide. No hype that's gone again in two years.
SQLite
If data needs to be stored, such as a sign-up list, I use SQLite : a database in a single file, without a separate database server that you have to secure and maintain. That file sits outside the web folder, so it can never be requested over the internet.
The web server
A server of my own with nginx and PHP, reachable only over a secure connection (HTTPS). I test every change on a test environment first. Then it goes live in a controlled way, with a backup beforehand.
File permissions
Every file gets exactly the permissions it needs: the web server may read, only the site itself may write. Sensitive files and admin scripts can't be opened through the browser.
Security, thoroughly tested
Forms are protected against spam and abuse, with a verification question, a security token and a limit per visitor. Everything a visitor enters is checked, and there are no email addresses on the pages. I test every change before it goes live.
Have I piqued your interest?
Send me a message and briefly tell me what you're looking for. Please leave your phone number too. Then we'll call first, with no obligation, and see what I can do for you.
Send me a message OK
Behind the scenes
SQLite, a database in a single file
SQLITE
one file
SQLite is a database: an organised store for data, such as a sign-up list, a product list or an app's settings. What makes it special is that a SQLite database consists of one ordinary file.
No separate server
Most databases run as a program of their own, a database server, that you have to install, secure, update and monitor. SQLite is built into the program itself as a library and reads and writes directly in that one file. So there's no server that can go down or be attacked, no passwords and ports to manage, and a backup is simply a copy of a file.
Reliable
Despite its simplicity, it's a full SQL database. A change is saved completely or not at all. Even after a power cut or a crash, the database stays in good condition.
You already use it, every day
SQLite is free to use (public domain) and, according to its own makers, probably the most widely used database in the world, even though you rarely hear about it. It's found in, among others:
Apple's iPhone, iPad and Mac (iOS and macOS), where many apps store their data with it;
Google's Android, and in the Chrome browser;
Microsoft's Windows 10 and 11;
the Firefox and Safari browsers;
apps such as iTunes and Skype, and, according to the makers, in most TVs and in the multimedia systems of cars.
A smartphone quickly contains hundreds of SQLite files. According to an estimate by the makers, more than a trillion (a thousand billion) are in use worldwide.
Why I use it
For a website like this it's ideal: easy to secure and back up, and little chance of failures. The file sits outside the web folder, so it can never be requested over the internet. That's how the Declaruur waiting list stores its sign-ups, and how this site counts visits anonymously: only totals per day, without cookies and without IP addresses.
When not
If a system is written to by thousands of people at the same time, a real database server is better. For most websites and apps, SQLite is more than enough.
Back to Behind the scenes OK
Ter Aar
The origin of the fox
Bailiwick of Voshol: Until 1834, Ter Aar belonged to the bailiwick of Voshol (a historic district run by a bailiff). Its coat of arms showed a fox: a “canting” coat of arms, a pun on the name Voshol (vos is Dutch for fox).Municipality of Ter Aar: Ter Aar adopted the fox in its municipal coat of arms, confirmed in 1816 by the High Council of Nobility: a red, climbing fox on gold.Now in Nieuwkoop: Since the merger on 1 January 2007, the red fox is in the coat of arms of the municipality of Nieuwkoop, which covers Ter Aar and Langeraar.
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