Another option you may want to consider is F#/Fable.
F# started out as "OCaml on .NET" pretty much and they are quite similar, but not identical. Fable is an F# to JS transpiler.
F# is described as a "functional-first" language, meaning that it is a multi-paradigm language, but the emphasis is on the functional parts.
Learning functional programming (or any type of programming) will not just be about picking a language, but also ecosystem and community.
As you note, ClojureScript is different from the others given that it is a dynamically typed language, while basically, all the others are statically typed languages. It will be a slightly different experience. If your preference is a typed language experience, others will be better. That would exclude Elixir also, which I think otherwise may be a nice option.
If you want to go with the same language for both backend (serverless) and some kind of frontend
my guess is either Purescript or F#.
I have dabbled with Elm and I like it, not server-side rendering though. I am mainly working with backend/infrastructure components. F# works where .NET works - you can use it just fine with AWS Lambda for example, although cold start times are not the best. I have yet to try it via Fable and Node.js runtime with AWS Lambda.
Seems there is at least a sample for F#/Fable for Cloudflare Workers in the Cloudflare docs, so someone there has tried that.
F# is actually the FP-related language I know the best 😁. I did not mention it because Fable feels like it's not taking off (I might be mistaken ?), and because as you mentioned, F# being somehow a bit OO-friendly, I would have a harder time not staying in my comfort zone. Moreover, I find F# abstractions somehow similar, but less powerful compared to Haskell/Purescript (I have a harder time extracting myself away from the imperative paradigm in F#). And I'm a bit attracted to the "pure+immutable by construction" guarantee.
Fable was definitely on my to-try-list, though... Do you have a feedback specific to Fable ? Have you tried it ? Do you have an opinion/advice on which libs to use ?
Regarding cold start times: If what you're trying to do is not computationally heavy (i.e. runs in less than 50ms of CPU time - excluding idle time when waiting for requests), and if the language you're using compiles to something that can be ingested by V8 (Javascript bundle/WASM) I'd strongly recommand Cloudflare Workers over Lambda: CF workers have a near zero cold start, and they are waaay cheaper ! Their approach is actually pretty clever: They dont spawn a whole isolated process (which has a lot of overhead), but rather execute each request in a V8 isolate.
To go full force into learning pure FP, then Haskell/Purescript is likely better. F# is perhaps not "taking off" in terms of widespread adoption, but I do not think you will get that with Haskell/Purescript for web app/serverless solutions either. I see F# as being more pragmatic than pure.
My hands-on experience with Fable specifically is very limited so far, unfortunately.
Cloudflare workers would have been useful if it was edge computing and not needed to be within the realm of the AWS ecosystem, e.g. running within VPCs, integrating with other AWS services. For a lot of these use cases though, a bit longer cold start is not an issue.
Dont get me wrong, I dont care working with a language that has a small community (I wouldnt explore FP, if I did). By "not taking off", I meant that I've not seen as much learning resources about Fable as for the others (and I was specifically thinking about Fable, not F#).
For further actions, you may consider blocking this person and/or reporting abuse
We're a place where coders share, stay up-to-date and grow their careers.
Another option you may want to consider is F#/Fable.
F# started out as "OCaml on .NET" pretty much and they are quite similar, but not identical. Fable is an F# to JS transpiler.
F# is described as a "functional-first" language, meaning that it is a multi-paradigm language, but the emphasis is on the functional parts.
Learning functional programming (or any type of programming) will not just be about picking a language, but also ecosystem and community.
As you note, ClojureScript is different from the others given that it is a dynamically typed language, while basically, all the others are statically typed languages. It will be a slightly different experience. If your preference is a typed language experience, others will be better. That would exclude Elixir also, which I think otherwise may be a nice option.
If you want to go with the same language for both backend (serverless) and some kind of frontend
my guess is either Purescript or F#.
I have dabbled with Elm and I like it, not server-side rendering though. I am mainly working with backend/infrastructure components. F# works where .NET works - you can use it just fine with AWS Lambda for example, although cold start times are not the best. I have yet to try it via Fable and Node.js runtime with AWS Lambda.
Seems there is at least a sample for F#/Fable for Cloudflare Workers in the Cloudflare docs, so someone there has tried that.
Not tried Purescript yet, on my list ;)
F# is actually the FP-related language I know the best 😁. I did not mention it because Fable feels like it's not taking off (I might be mistaken ?), and because as you mentioned, F# being somehow a bit OO-friendly, I would have a harder time not staying in my comfort zone. Moreover, I find F# abstractions somehow similar, but less powerful compared to Haskell/Purescript (I have a harder time extracting myself away from the imperative paradigm in F#). And I'm a bit attracted to the "pure+immutable by construction" guarantee.
Fable was definitely on my to-try-list, though... Do you have a feedback specific to Fable ? Have you tried it ? Do you have an opinion/advice on which libs to use ?
Regarding cold start times: If what you're trying to do is not computationally heavy (i.e. runs in less than 50ms of CPU time - excluding idle time when waiting for requests), and if the language you're using compiles to something that can be ingested by V8 (Javascript bundle/WASM) I'd strongly recommand Cloudflare Workers over Lambda: CF workers have a near zero cold start, and they are waaay cheaper ! Their approach is actually pretty clever: They dont spawn a whole isolated process (which has a lot of overhead), but rather execute each request in a V8 isolate.
To go full force into learning pure FP, then Haskell/Purescript is likely better. F# is perhaps not "taking off" in terms of widespread adoption, but I do not think you will get that with Haskell/Purescript for web app/serverless solutions either. I see F# as being more pragmatic than pure.
My hands-on experience with Fable specifically is very limited so far, unfortunately.
Cloudflare workers would have been useful if it was edge computing and not needed to be within the realm of the AWS ecosystem, e.g. running within VPCs, integrating with other AWS services. For a lot of these use cases though, a bit longer cold start is not an issue.
+1 on the "more pragmatic than pure" part 😊
Dont get me wrong, I dont care working with a language that has a small community (I wouldnt explore FP, if I did). By "not taking off", I meant that I've not seen as much learning resources about Fable as for the others (and I was specifically thinking about Fable, not F#).