That doesn't make sense, unless you're talking about a specific framework that has bad performance characteristics. Let's say you've got a request that does SS

That doesn't make sense, unless you're talking about a specific framework that has bad performance characteristics. Let's say you've got a request that does SSR and takes 500ms, with 450ms of that time spent processing the request and 50ms spent rendering the response. If you switch to CSR, you still have to wait 450ms to process the request, and you've got to serialize the response data (eg: render it to a more concise format than html) which is going to take some of that 50ms you're trying to save. So, where is the blocking you're talking about? How does CSR make it go away? What you wrote sounds like you're describing a singleton that handles all rendering for all requests, and can only handle one request at a time. If that's the case, your framework is a toy and you need to ditch it for something that can handle multiple concurrent requests independently of each other.