about
The person behind the products.
I’m Trevor Leeman. Leeman Software is my studio, the product studio of Leeman Group LLC, and I’m its only developer. I started with OSRS Exchange in 2022, and I’ve designed, built and run everything here myself since, from the first sketch to the servers.
The record so far
- players have used OSRS Exchange
- 500,000+
- items tracked across two games
- 11,500+
- commits since 2022
- 3,000+
- automated tests
- 4,900+
OSRS ExchangeSince 2022
I started OSRS Exchange in July 2022. More than 500,000 players have used it since, and it tracks 4,500+ items.
About OSRS ExchangeRS3 ExchangeSince 2026
In 2026 I reworked the platform to run two games from one codebase, each with its own items, tax rules and skills, and opened RS3 Exchange on it. It tracks 7,000+ items.
About RS3 ExchangeWallytIn testing
An app for splitting shared costs, built so one codebase runs on Android, iOS and the web. Android comes first: it’s in testing ahead of its Google Play launch.
About Wallyt
How I run them
Your card stays with Stripe
Premium is billed by Stripe. Card details never reach my servers, and you cancel from your account settings.
A person answers
Email and Discord messages come to me, the person who wrote the code, so the reply is from someone who can fix the problem.
Nothing ships untested
More than 4,900 automated tests cover tax rules, payments, alerts and currency maths. On the Exchange sites they run on every change before it goes live.
Numbers you can check
Prices come from the RuneScape Wiki’s public data, tax follows each game’s published rules, and Wallyt keeps the exchange rate with every expense it converts.
Servers I look after
Both Exchange sites run on servers I set up and maintain, behind Cloudflare, with errors reported to me as they happen.
Plain about limits
Each product’s page says what’s free, what isn’t and what it doesn’t do yet.
If I stop
One developer is one point of failure. This is what protects you if I’m ever not here.
Your records leave with you
Wallyt exports any group as a CSV file that opens in any spreadsheet, whenever you like.
You’d be told first
Wallyt’s terms promise notice by email or in the app before it ever closes, so you can export your groups first.
You can stop paying at any time
Exchange Premium is cancelled from your account settings, and you keep it to the end of the period you’ve paid for.
Work with me
I take on a few projects a year. If you need a web app, an Android app, or the payments, sign-in and servers behind one, you work directly with the person writing the code, from the first sketch to production. These are things I’ve built. Everything but Wallyt is live today.
Payments and subscriptions
Stripe checkout with free trials, sales tax, renewals and cancelling, kept in step with what each account can use.
Sign-in and accounts
Emailed codes, Google One Tap and Android’s account sheet, Discord linking, and bot protection at sign-up.
Live data at scale
Prices for 11,500+ items across two games, fetched around the clock, charted back years and watched by alerts every 6 seconds.
Apps for every screen
One React Native codebase for Android, iOS and the web, with end-to-end tests run on each.
Notifications people act on
A Discord bot and email delivery for price alerts, with retries and cooldowns handled.
Running it afterwards
Servers, deploys, error reporting and scheduled jobs, looked after by the person who built the product.