Launch HN: Ghostship (YC S25) – AI agents that find bugs in your web app

53•jessechoe10•4mo ago

Hi HN, we're Jesse and Gautham. We're building Ghostship (https://tryghostship.dev/).

Ghostship lets you find bugs in your web app by entering in your URL and describing a user journey.

Here's a video of Ghostship in action: https://www.loom.com/share/dec264ae32f94d50adb141c9246837c3?....

For over half our lives, we've been developers and we've done tons of user-facing projects like a coding competition I built called CerealCodes or freelancing projects on Upwork. The biggest problem we faced was that we shipped bugs in edge cases we didn't test, and the process of testing was annoying to do everytime we shipped a new feature. We tried automated testing tools, but those were flaky and couldn't adapt to feature changes. They also were really annoying to set up.

Our solution is to use browser agents to help you find bugs in your web app by clicking through your product like users would. You'd enter in your URL, describe what a user would do, and Ghostship would go through and try finding bugs by going through the user journey and extrapolating edge cases by visually seeing where else to click as it goes through each step in the user journey. We then show session replays of our agents going through your web app and list out all the steps it took.

We're able to find edge cases with almost no prompting. All you need to do is enter in one URL and one user journey (if you have login credentials on your web app, enter in some test credentials).

One bug we were able to find with Ghostship was on the YC application page. Apparently you could add your education dates in reverse chronological order (April 2022 to January 2021, which makes no sense).

Another bug we were able to find was a crypto smart contract CRM dashboard we vibe coded where we found a bug involving data corruption when you tried editing a draft contract multiple times.

You can sign up here: https://playground.tryghostship.dev/ for a limited number of credits. We'd love to hear from the HN community, whether you're building a web app for fun or a developer shipping a cool user-facing product to customers. We'd love to see what bugs we can find in your web app with Ghostship!

p.s. If you want Ghostship directly in your CI/CD pipeline and run after every PR, book a demo with us.

Comments

rgbrgb•4mo ago

This is awesome and an idea i've thought a lot about. In my experience, people either have flaky e2e tests or no e2e tests. How do you solve cost / margin? Is this an order of magnitude more expensive than my existing CI running playwright tests?

asdev•4mo ago

I've seen other YC companies do this exact thing and pivot. What's your differentiation?

m90•4mo ago

Typo on your landing page: "GitHub PR Intergration" -> "GitHub PR Integration"

handfuloflight•4mo ago

Price?

Mountain_Skies•4mo ago

I'm in no way affiliated with Ghostship so I'm not trying to talk on their behalf but my experience in this space is that token credits are sold by negotiated private contracts. Similar products and companies typically don't advertise standard fees for token credits, so there's very little price transparency. Maybe Ghostship will be different, which would be refreshing.

tarasyarema•4mo ago

If you register, you can see it's $5 per run (voyage)

just_steve_h•4mo ago

You know “Ghostship” was the name of an incredible East Bay artists’ community that was destroyed in a fire which killed multiple people. Is this really the name you’re going with? It’s not ancient history, either - less than 10 years.

lovich•4mo ago

Never heard of them. I have heard of the shitty 2002 film by that name.

I don’t know why someone would be expected to be aware of a niche, local, artist community or their history

fakedang•4mo ago

I haven't lived in the Bay Area ever, although I had plans to move there at the time (plans which were sidelined because I didn't get the H1B then), but the fire was pretty big news even halfway across the world.

https://en.m.wikipedia.org/wiki/Ghost_Ship_warehouse_fire

It wasn't the community that sparked attention, but the shoddy living conditions and that people had to resort to living in a warehouse in the Bay Area because of unaffordable housing (and which indirectly led to the conditions for the fire to happen).

But again I wouldn't expect recent YC people who just moved to the Bay Area to know about it.

lovich•4mo ago

I’ve never lived in the area, didn’t even know what city he was referencing with “East Bay” and I have been on hacker news since before this fire according to Wikipedia.

I have never heard of this event.

Also according to Wikipedia 36 people died. 31 people have died in Nepal due to their political shenanigans the past few days and I highly doubt anyone not involved in the region is going to remember in 10 years.

It seems really weird to me to be calling out random people for naming collisions with incredibly local, niche, news events from a decade ago

hluska•4mo ago

The Ghost Ship was massive news - it was the deadliest fire in Oakland’s history and the deadliest fire in the US since the Great White show at The Station in 2003. It had big impacts on everyone who threw renegade parties as it changed the liability from civil only to criminal against the master tenant and civil against both the city and the utility.

Finally, East Bay is a very common term, even encompassing a well known guitar player. Would you consider that if you’re not familiar with that term, you’re maybe not a very good judge of how common the knowledge of an event is? I’m from nowhere near San Francisco, but both East Bay and Ghost Ship are front of mind for me.

lovich•4mo ago

Bruh, I only need to extract this sentence fragment

> It had big impacts on everyone who threw renegade parties…

To point out that you are out of touch. How many people as a percentage of the population do you think even know what those are?

> Finally, East Bay is a very common term, even encompassing a well known guitar player. Would you consider that if you’re not familiar with that term, you’re maybe not a very good judge of how common the knowledge of an event is?

There is an East Bay in every single city with a West Bay. How many people as a percentage of population do you believe know specific guitar players names from niche bands like the Dead Kennedys ?

This entire thread reads like “how dare you not know the culture of San Francisco”

darepublic•4mo ago

There's a bit of history with js automation frameworks with spooky names. Ie phantom.js. I think a play on the idea of "headless" browser automation

cactusfrog•4mo ago

I know about ghostship, but I don’t immediately associate the word ghost ship with that disaster. I’ve always thought of them as the spooky abandoned ships that float around and I think it’s a good name.

evbogue•4mo ago

I immediately thought of the Oakland loft disaster in relation to this startup name -- but I'll admit I've been and on-and-off again loft occupant (not the ghostship loft, but other lofts) and East Bay/SF resident so that's probably skewing my view of this naming choice.

lovich•4mo ago

Man this is a tough crowd.

The product looks interesting. My only question would be what does a common successful description of a user journey look like?

Is it pages and pages of prompting to get the agents to understand or do you see success with less verbose descriptions?

minajevs•4mo ago

UI tests, and any automated tests in general, must be reproducible and deterministic to be useful. Do you position this product as an automated test tool, or useful “chaos monkey”?

Also a nitpick, but there are profanities on your landing page and it kinda puts me off.

dafelst•4mo ago

Genuinely curious, why does profanity put you off a product?

minajevs•4mo ago

That’s not the type of language I usually speak in professional context

tarasyarema•4mo ago

Completely agree with some of the comments, actually the hardest part is to execute these tests in a fast an reliable manner paralelizing the most of it, for your regression tests.

As we all know, in large orgs the form issue has been solved by using trusted components with unit tests. What worries me is how somebody were actually to provide valuable bugs, those that keep you up at night trying to fix them.

I worked with exploratory testing companies that would report hundreds of bug that nobody ever cared about. Does YC really care about the bug that they found, or have a business impact?

(Actually coming from building a company in this area now https://desplega.ai, you can try it out for free too)

ripped_britches•4mo ago

This is actually a great idea but my advice to you is to package it in some bigger kind of offering because this is a small niche.

And likely this type of thing is not suitable for CI use. CI systems are already too slow and flaky. You want to run this type of thing nightly.

For example look at supabase. They basically sell a DX CLI + UI as their core offering. But that’s not a real business. So they sell off the shelf AWS RDS + postgrest + gotrue and now it is a cohesive platform that you can charge real money for. But those pieces are just the easy to assemble legos around their core thing. Not to belittle how impressive they are at shipping, but a lot of what makes supabase great is the brilliant assembly of these preexisting components, wrapped in a delicious package

_1tan•4mo ago

We use Gitlab. Is that planned?

Terretta•4mo ago

Home page a stuttering lagscape in Chrome (Edge) on Android tablet.

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Launch HN: Ghostship (YC S25) – AI agents that find bugs in your web app

Comments