MacTech Spotlight: David Sinclair

Last year I was featured in MacTech magazine as their developer spotlight for the month. They asked me some questions about my background; here are my responses:

What do you do?

Dejal is a small ISV, so I do pretty much everything, including Cocoa development, customer support, accounting, PHP web development, graphic design, etc. I do have a developer that helps with Dejal Simon plugins etc, and I've used graphic designers for some app icons and the new Dejal logo. In addition to my own products, I do contracting work part-time.

How long have you been doing what you do?

I learned BASIC in 1982 as my first programming language, and knew that's what I wanted to do with my life. In 1988 I switched to Pascal on Mac Pluses at the University of Auckland in New Zealand, and started playing around with apps, but didn't sell anything until I created Dejal (originally called Dejal Userware, for user-friendly software) in 1991. Back then it was just a hobby, selling utilities for System 5 through Mac OS 9 (they're still available as freeware: There wasn't a web back then, though; I distributed my software via Compuserve, AOL, floppy disks, and later CDs, and provided licenses via airmail (from New Zealand), hand-written on photocopied certificates.

When my wife and I moved to the US in 2001, I learned Cocoa, developed my first Mac OS X apps, and registered my company as Dejal Systems, LLC in 2002.

Your first computer:

I got my first computer in 1983: a Sinclair ZX81, with 3.25 MHz Z80 processor, 1K of RAM, a cassette tape drive, tiny membrane keyboard, and hooked to a B&W TV. I first used a Mac at school: an original 128K Mac in 1984... but I didn't own one until I got a Mac Plus in 1988.

Are you Mac-only, or a multi-platform person?

Definitely Mac-only. I have a Windows box I got a few years ago for a project, but it just gathers dust.

Do the products you develop scratch a personal itch, or are they for others?

A bit of both. Obviously I need to keep marketability in mind when working on products. Most started out as fulfilling a need I didn't see being adequately serviced with existing products in the marketplace. Narrator started as a fun way to learn Cocoa. Simon began as a way for me to watch for website updates, and became more sophisticated as it became popular. I created Time Out to improve my health, since I can suffer from eyestrain when staring at a computer for hours on end. Caboodle was written to compete with others in the snippet-keeper market, as I didn't really like the approach existing ones took. Macfilink was created in partnership with an affiliate marketer to serve that community. BlogAssist was written specifically for my wife, who was really into LiveJournal blogging at the time. All of the products have grown and evolved over the years based on customer feedback -- it's really important to listen to what people say about products and incorporate their ideas into the design, as makes sense. I keep track of all suggestions, and tally votes for them to determine the most requested enhancements, to which I give priority when deciding on features for an update.

What's the coolest tech thing you've done using OS X?

One thing I'm quite pleased with is the Script plugin in Dejal Simon. Simon is a server monitoring tool that uses a plugin model for services, notifiers, and reports. The Script plugin allows running AppleScripts, shell scripts, Perl, Python, Ruby, or other scripts to perform checks and notifications for local or remote servers and processes. I like it as it leverages Mac OS X's unix underpinnings to significantly enhance the reach of the product. That would've been much harder under Mac OS 9 or Windows.


I wrote an integrated environment for an old SpectraVideo MSX computer (loaded off 5.25" floppies) around 1986, complete with a basic word processor, spreadsheet, and more. It was never released, though.

Where can we see a sample of your work?

Try my products: free trials are available at

See my code: open source Cocoa at

Read my thoughts: subscribe to my blog at

The next way I'm going to impact IT/OS X/the Mac universe is:

I'm excited about the upgrades of the Dejal apps for Leopard. Simon 3 and Time Out 2 will be major upgrades, with much-improved UI and features.