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Comment by rkrzr | Hacker News Reader

> Just like you never want to be the smartest person in a room, you never want to be the one pushing a language to its limits.

(Channable co-founder here) If everybody took this view, then a language could never improve. I have actually been very impressed with how far we have been able to take Haskell before having to push its limits. Anecdotally, we previously were using Scala (and Spark) and ran into issues much earlier. In those cases we were pushing the limits of Spark, but underlying those were the limits of the JVM.

> IMHO when you’re providing language patches you probably choose the wrong language.

This is a very myopic view. There is much more to consider when choosing a language (what kind of team do you have, what kind of problems are you working on, maintainability, performance, ecosystem, hiring, etc.).

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I really appreciate your view on all this, and I totally agree with you that the other commenter has a very nearsighted perception of things.

I think the go-to example of a group taking this to the extreme is Jane Street with OCaml. For many intents and purposes, Jane Street are really the major shepherds of the language these days. They contribute tons of compiler fixes and improvements, and have written their own replacement of the standard library (which is used by many people). I think it'd be silly to say that they "chose the wrong language"; rather, they've invested in a language ecosystem that benefits them and reflects their needs, while at the same time growing and improving a whole language community. That's an awesome feat.

That's how I see it as well - Haskell has been very beneficial for us as a company, so it's nice if we can also contribute something back to the community.

The difference here is scale: Jane Street is a 20 year old company with over 1000 employees, Channable has maybe a fifth of that. The proportion of engineering effort that will have to go into language expertise will just be higher at a smaller shop pushing the bounds and this will simply take away from feature development.

I've worked writing Haskell in multiple shops, seen it be successful, and also seen it fail to many times. This is a huge issue for adoption: that an engineering team using Haskell will have to devote a significant amount of time/effort to tooling/resuability/infra that would otherwise be available to directly deliver value to customers if they had gone with a different language. Stuff like pagination, custom json/typescript encodings and route generation, organizing the code base so complication time isn't a nightmare, these are all "inner source" projects I've worked on that needed to be done for us to use Haskell for a decent sized team. The fact that Channable had to go down the road of ghc-compact regions, to me, suggests that on a strictly technical basis they would be much more productive using a language like Rust of C++. Better for their end users, and better for their investors.

Of course, large companies can make these deep investments into languages, tooling, and infrastructure (and by all accounts Channable is well on their way) but when they do it's only a small proportion of their entire dev team. For Haskell, I contend that its' lack of state of the art library support and tooling is a massive impediment to wide scale adoption: companies just don't want to put 1/3 of a 30 person dev group on a "platform" team in order to be productive.

> I've worked writing Haskell in multiple shops, seen it be successful, and also seen it fail to many times.

Can you share some of the successes, failures, and composition of teams Haskell experience?

Also any success/failure causes you believe they had in common.

Any team is eventually going to have to invest in tooling. If they had gone with C++ they would be fighting different fires: memory safety problems, build tool complexity, bloated compile times, memory leaks, etc. If they went with Javascript; run-time errors, async memory pressure, complex deployment artifacts, etc.

Haskell has benefits for its trade-offs. Its type system is world class. I get a lot of leverage out of its type class constraint resolution. It has a sufficient compiler that generates good, fast code and a run-time system that makes dealing with concurrency much safer and easier than other systems I've worked with.

You can choose any language we have out there right now and a decently sized engineering team, if they're smart, are going to have an internal team or some amount of their backlog of work dedicated to tooling. Even Twitter has a tooling team! And Java has an ecosystem where millions of dollars of full-time engineers are building IDEs and DUX tools constantly.

It's the nature of the beast.

yes, but I'd argue the "buy vs. build" balance is shifted too far to the build side right now when you build all your backend services (or most of them) with Haskell. In the Haskell ecosystem there's a good deal of solutionism, but this can be solved with diligent decision making and good technical leadership, the greater issue, IMO, is that Haskell lacks the breadth and depth of libraries that allow Haskell to be a low risk language choice that allows you to build a project, see how things go, then restart with a different team/assumptions if need be.

I want Haskell to win and solve these problems: I've invested years of my life learning the ecosystem and actively maintain open sources libraries, but after years of using the language and running into problems, I've lived through the situations when Haskell is less than stellar as a software engineering tool and it's quite disappointing to see.

I think the only solution here is to dump a war chest of cash into the ecosystem.

One the reasons Java and C++ are incumbents is due to the network effects that made them what they are today. Oracle literally spent hundreds of millions of dollars convincing developers Java was the next big thing. C++ enjoyed platform support by being compatible with C and was embraced by big players with deep pockets.

Haskell doesn’t have a shot at becoming “a safe choice” in that regard. It's not an exclusive language to a desire-able platform, it doesn't have an organization with deep pockets to fund its development, it doesn't have a killer application.

But it is an oracle for the future of where programming is headed. Many languages are trying their best to steal ideas from Haskell/FP: immutable data structures, pattern matching, lambda functions, lack of null, constrained parametric polymorphism, etc; patterns from libraries like monads, streams, lenses, functors; all making their way into Java, C#, etc.

That being said I haven’t felt that the ecosystem is lacking core libraries for almost anything I’ve been working on. The IDE support is still lacking and profiling tools are there but lacking shiny DUX. Otherwise I can’t really complain.

Calling compilation time "complication time" is such a good typo

Jane Street's been doing this for most of their existence. I interned there a decade ago when they had 300 people and maybe 100 engineers and they had already built up an impressive internal infrastructure—including lots of in-house tools (eg a code review system) that were custom because they got value from building them in-house, not because of OCaml. At that point, they had been on this trajectory for a decade already, certainly well before they had a massive team of developers. I forget the exact details, but they started using OCaml in the early 2000s when the entire company had a single-digit or maybe low-double-digit employee count.

Building internal tools, libraries and expertise was clearly a massive net gain in productivity for them—it did not "take away from feature development" in anything but the most superficial and short-sighted accounting. Most recently I worked at Target and the contrast was pretty extreme: on a lot of fronts, Jane Street had better in-house systems than Target had with thousands of tech employees pushed to use mainstream technologies and existing open source systems. It's obviously not a 1:1 comparison, but seeing how productive a relatively small organization like Jane Street could be despite (or, really, thanks to) building a ton of things in house really got me to question the traditional wisdom here.

Of course, everything you've said is a real obstacle when that's how managers or other teams think, regardless of whether it's accurate! Dealing with perception and legibility is definitely one of the difficulties in trying to have a Haskell team in a big company. "Nobody got fired for IBM" isn't so much a cute aphorism as corporate gospel—even if they probably should have been.

Would you even know what Jane Street was if they didn’t stand out in this way?

Seems like a good way to get smart people interested in working with them.

Can you talk more about what kind of limits you hit with Scala and Spark? I definitely have my own biases, but my feeling is you get 95% of the good stuff of Haskell while avoiding most of the problems mentioned elsewhere in this thread (e.g. you get a proper IDE-integrated debugger with breakpoints/stepping/etc. that Just Works).

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