Do Vibe coders actually test things?
If the agent writes the code… who’s actually testing it?
Do you still go through edge cases and user scenarios manually, or are you also delegating “please break my app” to another agent now?
Has testing become more systematic and automated in your workflow, or you just moving faster with fewer guardrails (and let users break things) ?
Also, do you test any of your endpoints?
Preparing for a launch soon and looking to connect with people that love breaking APIs and automate flows.
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Nikolas
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i think experienced vibe coders test aggressively because they know AI can be surprisingly right and surprisingly wrong at the same time. I always verify functionality before calling anything finished.
@simran_kumar i think the good coders do. For me, building something is only half the job; testing is what tells me if it actually works
@simran_kumar @deangelo_hinkle I use vibe regularly, but I never skip testing. Generating code quickly is great, yet I still verify edge cases, user flows, and expected outcomes before I trust the result.
@simran_kumar @deangelo_hinkle @lakeesha_weatherwax I've noticed there's a huge difference between writing code and validating it. I'm much more confident in code after I've tested real scenarios.
@simran_kumar @deangelo_hinkle @lakeesha_weatherwax yes, somewhere you have to put the hard work, and testing is surely one of these areas
Propane
@simran_kumar @deangelo_hinkle exactly this. if anything i've gotten more paranoid about testing since using vibe tools. you move fast and there's always the chance it missed something subtle. i usually write a few quick manual tests first before i trust the generated code in production
@simran_kumar @deangelo_hinkle @atherkildsen Same here. AI has definitely made me ship faster, but also made me much more careful. It's easy to get something that "looks right" but fails in a real-world scenario.
For me, the real question isn't whether vibe coders test things, it's how they test them. I always run through real scenarios because code that looks right isn't always code that behaves right.
ApyHub
@henry_lindsey good point!
I'm usually asking Claude to write unit tests and integration tests after it wrote some code under my supervision - therefore trying to always stay covered :)
ApyHub
@sk_uxpin thats a good one. And do you write your own test cases or claude does?
@sk_uxpin I also ask Claude to generate both unit and integration tests, but I rely a lot on behavioral/UI tests as well — especially ones built with Maestro. They’ve become a really important safety net for end-to-end user flows.
I still test the important flows myself especially when APIs or user data are involved. For small internal tools I move faster but I don't fully trust agent output w/o checking it. Do you use a separate agent just for breaking/testing the app?
ApyHub
@ada_johnsen no, I dont use...I agree, I also mostly test when external API are involved!.
what external apis do you use?
For testing, creating good evals is critical! Both offline & online eval dashboards. Online evals run with every user so you can see performance in real time. Offline evals are created to pressure test before launch, so that users don't break things to begin with. This Lenny's podcast episode on evals was super useful for me: youtube.com/watch?v=BsWxPI9UM4c
Honest answer: I test the happy path and let users stress test everything else. The agent writes it, I click through the main flow, ship it, and wait for something to break.
It's not great practice but it's the reality when you're moving fast solo. The upside is bugs surface faster when real people are using it. The downside is sometimes real people are using it when it breaks.
Haven't gone as far as delegating testing to another agent yet but I've seen people doing that and it actually makes sense. If the agent wrote it, another agent probably knows where the weak spots are better than I do.
Endpoints? Barely. That's usually where things catch up with me first.
Honestly, I think the answer depends on what you mean by "test." I run my vibe-coded stuff through the happy path and maybe 2-3 edge cases manually, then ship it. For internal tools and prototypes, that's been enough. For anything touching user data or external APIs, I'll ask Claude to write unit tests after the code is done. Not perfect but it catches the obvious stuff.
The real gap I've noticed is integration testing. The AI writes clean isolated functions but the moment two pieces need to talk to each other, things break in ways that unit tests don't catch. That's where I still end up debugging manually, which kinda defeats the speed advantage. Anyone found a good workflow for testing the "glue" between components?
PopShort.Al -Stream Short Drama
Interesting question.
We see a similar pattern in AI filmmaking.
The bottleneck used to be creation.
Now the bottleneck is validation.
AI can generate a script, a character, a scene, even an entire short drama.
But determining whether the story will resonate with real audiences is still surprisingly difficult to automate.
Makes me wonder if the next generation of AI tools won't be better generators, but better evaluators.
Looking forward to seeing how you're approaching this problem in the API and developer tooling world.
ApyHub
@elara_thorn I totally agree.
things are similar in the dev tooling space + whats key is test automation and scripting.
I think it depends a lot on the maturity of the vibe coder.
For me, the foundation is a spec-driven approach. Before any coding starts, I need clear user scenarios documented in Markdown files. The spec becomes the source of truth.
After that, I either go through those scenarios manually or ask agents to execute and verify them. So yes, testing is still happening — often more systematically than before.
The bigger issue, in my opinion, is that many projects don’t have clearly defined scenarios at all. If the expected behavior isn’t documented, neither humans nor AI can reliably test it. That’s where most testing problems actually begin.
in my experience , the best vibe coders treat testing as part of the creative process. I'm not interested code that only works in theory .