A great tool to help you discover the technology being used by a variety of websites. I was impressed that upon signing up that I had full access to a free list of leads.
Based on our record, BuiltWith seems to be a lot more popular than grep.app. While we know about 162 links to BuiltWith, we've tracked only 15 mentions of grep.app. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Https://grep.app - To search repos for patterns. I usually use it when I'm using an obscure or badly documented library. https://unicode.scarfboy.com/ - Unicode stuff. There are a lot of small Unicode tool sites. - Source: Hacker News / 3 months ago
There are some alternatives like https://grep.app or https://sourcegraph.com/search if you want fast live search, but at the end of the day these are generally expensive services to provide, especially for free anonymous users, so you should probably at least accept that service providers can and do change things like this. You can also run something like your own copy of Zoekt and then ingest repositories on... - Source: Hacker News / 9 months ago
Https://grep.app/ is another good one. Not sure how many repos they index though. - Source: Hacker News / 10 months ago
Https://grep.app/ is similar and seems to return results, but I have not compared it to native GitHub search. - Source: Hacker News / 12 months ago
Https://grep.app/ has served me well for the last couple of years finding snippets for random APIs. But recently I found that certain strings from open-source projects suddenly yield no results. For example: VaultServiceTimeout from https://github.com/rajanadar/VaultSharp has no results for https://grep.app/search?q=VaultServiceTimeout. Is there some alternative service for this task that is up-to-date? - Source: Hacker News / about 1 year ago
Evan You, creator of Vue.js, is a prime example. Vivek Nair, Co-Founder of BotGauge, notes that You “created something that addresses real developer needs with clean logic and thoughtful design.” Vue.js powers over 1.5 million websites in 2025, a testament to its scalability and developer trust, as reported by BuiltWith. You’s ability to build a framework independently, without corporate backing, underscores his... - Source: dev.to / 10 days ago
There exist websites like https://builtwith.com so answer to your question is yes. - Source: Hacker News / 5 months ago
BuiltWith says the web client is NextJS which is interesting as ChatGPT made a big switch away to Remix IIRC. https://builtwith.com/?https%3a%2f%2fclaude.ai%2fnew. - Source: Hacker News / 8 months ago
Also, wow that is an obsene amount of libraries they use: https://builtwith.com/?https%3a%2f%2fspectrum.ieee.org%2fdisney-robot-2668135204. - Source: Hacker News / about 1 year ago
I would say run both sites through https://builtwith.com/ to get what all they used in the building process. Source: over 1 year ago
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