PartsTree on Replatforming in Peak Season After 20 Years of Homegrown Code

PartsTree has sold replacement parts for lawnmowers and other outdoor power equipment for about 20 years, mostly on software its own team built. By this year the code had become something nobody wanted to touch. Some of it was written more than 20 years ago, and only one person could fix it when it broke.

Vinny O’Brien sat down with Doug and Drew from PartsTree and Chris from Altus Nova at Shoptoberfest 2026 in Nashville to talk about the move to Shopware. It was Altus Nova’s first Shopware project. PartsTree’s rule had always been to change systems between late October and January, because May and June sales run about four times January’s. They went live in mid-July anyway, after years of watching their own suppliers stumble through mid-season migrations.

Chris explains why the team gave up most of its custom logic for platform defaults and kept customization for the few things core to how PartsTree works. Doug and Drew talk about bringing staff along when the switch landed in their busiest months, and about how much of the business runs on what long-serving employees know and never wrote down. Doug says he doesn’t know yet how AI agents will change the way customers buy parts. Drew has a warning from data cleanup, where an AI-written product description turned a blower into a Glock pistol. Chris thinks the bigger opening is B2B, such as shared accounts that let a landscaping crew in the field and their mechanic work out a repair together.

The new site now ships weekly releases. The team says the main metrics match or beat the old site’s, and some secondary ones are still being tuned.