OxCaml
Hacker ApprovedRanked 11 of 26 compilers by recommenders
Jane Street's production OCaml compiler fork adds modes and zero-allocation features for safety and performance, though its interfaces are still emerging and it still needs a runtime.
Jane Street's production OCaml compiler fork adds modes and zero-allocation features for safety and performance, though its interfaces are still emerging and it still needs a runtime.
20 people gave an opinion
- recommend it
- 17
- criticize it
- 3
- approval share
- 85%
Recommended in 7 of 13 months
- November 2025: recommended
- December 2025: recommended
- January 2026: recommended
- February 2026: recommended
- March 2026: not recommended
- April 2026: not recommended
- May 2026: recommended
- June 2026: not recommended
- July 2026: recommended
- August 2026: not recommended
- September 2026: not recommended
- October 2026: recommended
- November 2026: not recommended (month in progress)
Why it carries the badge
- 17 people recommend itNeeds 10 or more, met.
- 5.7 recommenders for every criticNeeds 2 to 1 or better, met.
- Recommended in 7 of 13 monthsNeeds 4 or more, met.
The same three rules apply to every product, and the badge can’t be bought. How the badge works
What people say about it
The reasons people give, with the number of comments that give each one. Open a reason to read what they said.
Why people recommend it
Each mark is one comment
Strong types and modes
“That is exactly what OxCaml's mode system gives you: zero minor GCs on the dispatch loop in the post”
Comment from 15 May 2026 in “O(x)Caml in Space” “OxCaml's strong types and modes seem to serve as great testable oracles to guide the agents.”
Comment from 15 May 2026 in “O(x)Caml in Space” “reminds me a lot of modes from Jane Street’s OxCaml which is really interesting to me”
Comment from 11 Oct 2026 in “Valen's Memory Safety: A New Kind of Borrow Checking” - Comment from 15 May 2026 in “O(x)Caml in Space”
Zero-allocation and performance features
“That is exactly what OxCaml's mode system gives you: zero minor GCs on the dispatch loop in the post”
Comment from 15 May 2026 in “O(x)Caml in Space” “you can write very high-performance code that effectively never uses a GC”
Comment from 10 Jan 2026 in “Httpz – Zero-Allocation HTTP/1.1 Parser for OxCaml” “I really liked OxCaml's zero_alloc feature”
Comment from 29 Oct 2026 in “noalloc: Tooling and libraries to enforce zero heap allocations in Golang” Ergonomic and safe high-level language
“OxCaml is inspiring me lately as it's an ergonomic high-level language that also represents the machine.”
Comment from 17 Jan 2026 in “High-Level Is the Goal” “OxCaml shows you can have safety and ergonomics together”
Comment from 15 May 2026 in “O(x)Caml in Space” “they are a lot more ergonomic than Rust's approach”
Comment from 25 Jul 2026 in “Memory Safety Absolutists” Active improvements and tooling
“The Jane Street work on OxCaml is terrific after a long period of stagnation with the language.”
Comment from 3 Feb 2026 in “The Sovereign Tech Fund Invests in Scala” “The folks over at Jane Street have put a lot of effort into tooling recently.”
Comment from 30 Dec 2025 in “Go Away Python” “great to see the OCaml improvements”
Comment from 15 May 2026 in “O(x)Caml in Space”
Other compilers people recommend
The four most recommended other compilers, with the same counts for each, so you can compare like for like. The tick on each bar marks the 2 to 1 line the badge needs.
| Product | Recommend | Criticize | Approval | Months | Owned | Badge |
|---|---|---|---|---|---|---|
| GCC | 138 | 123 | 53% | 12 | 15 yrs9 owners | — |
| Clang | 74 | 50 | 60% | 12 | — | — |
| Free Pascal compiler | 38 | 7 | 84% | 11 | — | Approved |
| GraalVM Native Image | 31 | 9 | 78% | 11 | — | Approved |
| OxCamlThis page | 17 | 3 | 85% | 7 | — | Approved |
What people said
30 of the 33 comments that mention it, newest first. Each links to the original comment.
“I really liked OxCaml's zero_alloc feature”
“reminds me a lot of modes from Jane Street’s OxCaml which is really interesting to me”
“I rather have the option of Swift 6, Linear Haskell, Koka, OxCaml, Scala 3, and co.”
“they are a lot more ergonomic than Rust's approach”
“I would rather count it when they finally manage to upstream everything to OCaml”
“Sounds like OxCaml is pretty close to what you want.”
“great to see the OCaml improvements”
“OxCaml still requires a runtime, so it's not suitable for some applications”
“That is exactly what OxCaml's mode system gives you: zero minor GCs on the dispatch loop in the post”
“I'll have to take a look at OxCaml”
“OxCaml has some of this now”
“the static type system rejects inconsistent annotations”
“OxCaml shows you can have safety and ergonomics together”
“OxCaml's strong types and modes seem to serve as great testable oracles to guide the agents.”
“I think robustness is helped a lot by the fact that it’s the production compiler used at Jane Street”
“OxCaml's a surprisingly robust compiler for being packed full of bleeding edge extensions”
“I think the OxCaml [1] and Scala 3 [2] approaches are better.”
“The Jane Street work on OxCaml is terrific after a long period of stagnation with the language.”
“it's cutting edge stuff and the interfaces are still emerging, but it's great fun if you don't mind some pretty hardcore ML typing”
“It's too difficult right now to directly jump to the functional version”
“The local stack allocation mode puts in quite a strong constraint on the shape of the allocations that are possible.”
“Looks like 0xcaml continued trend.”
“OxCaml is inspiring me lately as it's an ergonomic high-level language that also represents the machine.”
“they are doing fascinating work that leverages a lot of research that interests me”
“you can write very high-performance code that effectively never uses a GC”
“I'm excited to see what comes of OxCaml the next few years.”
“The folks over at Jane Street have put a lot of effort into tooling recently.”
“which doesn't work with all the OCaml packages”
“it's primarily performance or parallelism safety features.”
“the syntax is not as concise / clean as Python”
Counts come from 1,795,640 Hacker News comments, November 2025 to November 2026. How we count. Report a mistake.