There's always been a long list of wants for the software, both mine and things that all the users of the system have asked for over the years. That very real list runs well over 100 items long.
Not too long ago – mid-March (2026) – my friend convinced me to give Claude Code a try. At the time I had been working on porting Moneylender's interface to a website for three years. I had several key pieces set up (the main window, recording payments, sending statements, and running reports), but in total I had migrated 9% of Moneylender's ~180 separate windows to the Online version of the software. While the backbone of the system is identical between desktop and website, the user interface (the text, buttons, input boxes, datepickers, and everything you see with your eyes when you use Moneylender) needed to be rewritten in a different programming language (translating the desktop's XML to HTML/CSS for the web).
The main window – one of ~180 windows making the trip from desktop to web.
I installed Claude, showed it Moneylender's source code and asked it to convert five specific windows from the desktop to the web. It thought for about 18 minutes and said it was done. I checked and everything it did worked pretty well. In 18 minutes, it did the tedious, mind-numbing work that would've taken me perhaps a week to do poorly.
For the next six weeks, I prompted Claude and checked the results, both in functionality and code architecture. Moneylender is my baby, and nobody gets to break my stuff. But Claude did a remarkably good job of following my coding style and architecture. When I didn't like how it arranged the code, a prompt or two got everything back on track quickly. And at the end of six weeks, Moneylender Online had 99% of the windows converted, tested, and working cross-compatibly with Moneylender Desktop.
In the midst of those changes, I wanted to see how clever it was at adding something new to the system. We had just migrated the template designer and after much back-and-forth, the web version was doing all the fun things the desktop one can do. So I asked Claude to do something I'd tried and failed at least twice in the past. I asked it to write an importer that would take a .docx file and convert it into Moneylender's native template format. It thought for about 16 minutes and said “all done”. Indeed, a new “W” button appeared on the template designer. I clicked it, chose a Word docx, and near-instantly I had a replica of that document as a brand new template in Moneylender. We did a little back and forth to address some measurement specifics about the height of paragraphs and stuff.
A Word document in, a native Moneylender template out.
Something that had defeated me because the time sink and inevitable bugginess of my solution was excessive was simply done and over and working perfectly in about an hour.
Needless to say, I'm hooked. I've been writing software for 31 years. I've written so many websites I'm totally bored of that kind of work. AI coding tools have taken the painful bulk of the work away, so I can focus on interesting architecture, performance, and interconnectivity problems once again.
In the last couple months, we've run down dozens of rare errors that pop up in Moneylender error reports. We've added polish to places where the program has always been clunky. We improved the performance of the file system more than 5 fold. It's been an absolute joy to be partner programming with a system that can understand my hand-written systems and play with them with at least as much skill as I do.
Many longstanding items from that 100+ to-do list have already been knocked out, and I have a personal wishlist I'm tackling slowly and carefully, because the system's integrity is my primary responsibility. I'm so excited to finally be able to incorporate all the wonderful enhancements that will make the lives of Moneylender users better.
Just recently, the SmartSend system — so statements and late fee notices can truly be a one-click proposition — went live. Something I've wanted to make for years. I could go on forever. The takeaway is that this is a pretty great tool to help make Moneylender better for everyone.