"I test in prod" is the developer's confession that code met real users before it met a test suite. "Prod" is short for production, the live system customers use. The testing in production meme is funny because it's half true: plenty of serious teams do test in production, on purpose, with the right safety nets.
Our favorite testing in production meme designs
The meme lives on shirts as much as in Slack. Here are eight of our own designs. Every one is a Code Culture original.
i test in PROD T-Shirt. The short version, no apology.
Prod Is My Staging Environment Shirt. For teams whose staging server is a rumor.
Can We Test It On Prod Sweatshirt. The question every standup dreads.
Not Tested Just Trusted Shirt. Confidence as a deployment strategy.
Stay Calm and Deploy to Prod Shirt. Calm optional.
Vibes Immaculate Tests Skipped Prod On Fire Shirt. The vibe coding edition.
It Worked In Prod Sweatshirt. Past tense. Briefly.
Unbothered In Prod Capybara Shirt. For the on-call engineer who has seen everything.
Where "I test in prod" comes from
The long form of the joke is "I don't always test my code, but when I do, I test in production." It's a parody of the Most Interesting Man in the World ads. Charity Majors, cofounder and CTO of Honeycomb, called it "one of the sturdiest tech memes of all time" in her November 2021 essay for Increment, "I test in prod".
Over time the short form, "I test in prod," became the one people put on stickers and shirts.
What testing in production really means
Here's the twist. Majors' essay argues the opposite of the joke. Its subtitle reads: "Testing in production is a superpower. It's our inability to acknowledge it that's the trouble."
The idea is that staging is never a perfect copy of production. Real traffic, real data and real scale find bugs that a test server can't. So mature teams don't avoid production. They test there carefully, using a few standard tools.
- Feature flags. An article on Martin Fowler's site describes feature toggles, also called feature flags, as "a powerful technique, allowing teams to modify system behavior without changing code." You ship the code switched off, then turn it on for a few users at a time.
- Canary releases. Google's SRE workbook defines canarying as "a partial and time-limited deployment of a change in a service and its evaluation." A small slice of users gets the change first. If the numbers look bad, you stop the rollout.
- Smoke testing in production. Right after a deploy, run a quick check that the most important paths still work: the site loads, people can log in, checkout goes through.
The difference between the meme and the practice is control. The meme is shipping blind and hoping. The practice is shipping small, watching closely and being able to roll back fast.
The meme family
"I test in prod" sits in the middle of a whole story. Upstream is "it works on my machine", the reason nothing got tested locally. Downstream is breaking prod, the natural result. And over all of it hangs the rule to never deploy on Friday.
FAQ
What does "I test in prod" mean?
It means testing code in the live production environment, with real users, instead of (or as well as) a staging environment. As a joke, it means skipping tests entirely. As a practice, it means testing carefully in production with feature flags, canary releases and monitoring.
Is testing in production ever a good idea?
Yes, when it's controlled. Teams use feature flags, canary releases and smoke tests to check changes against real traffic while limiting the damage if something goes wrong. Shipping untested code straight to everyone is the version the meme is laughing at.
Where does the testing in production meme come from?
It parodies the Most Interesting Man in the World ads: "I don't always test my code, but when I do, I test in production." Charity Majors called it "one of the sturdiest tech memes of all time."
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