Big data, little changes
Etsy's continuous deployment approach sets up an ideal scenario for tying single, isolated site changes to experiments, and it makes it easy to identify the culprit if a code change causes problems.
"When you make multiple changes to a site or a page, it's hard to figure out what's not working the way you want it to," Mardenfeld says. "When you change one thing at a time, you're able to see where you went down the wrong path and can backtrack very easily."
Another benefit of continuous deployment is the ability to pull the plug on a code change that didn't live up to expectations. "We're more likely, we think, to notice that we're doing something that's bad and to stop," McKinley says. "Whereas operationally and emotionally, if you work on something for many months and then release it, there's nothing that will stop you from releasing it because you're invested in it."
Most often, the changes yield modest gains with minimal impact -- and that's the plan. "We're playing with peoples' livelihoods here, so it behooves us to be very careful," McKinley says.
Being able to improve business for the 800,000 craftspeople and small business owners that enable Etsy's existence is a motivator for employees.
"It feels really good at Etsy to be optimizing something that's not just about a corporation's bottom line," Thomas says. "The work we're doing, the ways that we're looking at data and using it to make things better, is all about helping the sellers on Etsy to be more successful."
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