May 15, 2026
Unsafe at any speed? Not anymore
Erlang/OTP 29.0
Erlang gets stricter, safer, and the comments are already side-eyeing the future
TLDR: Erlang/OTP 29 makes the platform safer by default and adds experimental new data features, plus better tools for colorful terminal apps. Commenters loved the security lockdown, got curious about the new records, and immediately turned “unsafe” warnings into a Rust joke.
Erlang/OTP 29 just dropped, and while the release notes are packed with serious upgrades, the real show is in the crowd reaction. The biggest applause line? Security. Commenters were thrilled that the built-in remote access tool now starts with risky features turned off by default, with one reader flatly calling it a “good security change.” In plain English: the software is making it harder for people to accidentally leave a door open, and the community seems very into that grown-up energy.
But this wasn’t just a boring safety lecture. People also perked up over a new color-and-styling terminal tool, with fans saying Erlang has long felt a bit weak for fancy command-line apps and this could finally give it some flair. Then came the inevitable “wait, what even is OTP?” moment, when one commenter basically asked for the inside story and another jumped in with a mini explainer: OTP is the reliability playbook that helped make Erlang famous in phone systems and other “please don’t crash” jobs. Yes, the comments turned into a pop-up history lesson.
The spiciest curiosity, though, was around new “native records,” an experimental way to handle data. One commenter said they’re watching closely to see how that lands across the ecosystem, which is polite code for this could get messy. And of course the comedy arrived right on cue: after the release added “unsafe” labels for sketchy functions, one joker deadpanned, “Right in time for the Rust rewrite! /s.” In other words, classic developer banter: half excitement, half suspicion, all drama.
Key Points
- •Erlang/OTP 29 introduces security-focused defaults, including disabling SSH shell and exec services by default and no longer enabling SFTP by default.
- •The release makes the post-quantum hybrid algorithm x25519mlkem768 the preferred default SSL key exchange group.
- •New features include io_ansi for terminal styling, ct_doctest for testing documentation examples, experimental native records, is_integer/3, and support for multi-valued comprehensions.
- •Compiler and runtime improvements include better JIT code generation for certain binaries, improved map comprehension code generation, and new compile-module guidance for BEAM language implementors.
- •Erlang/OTP 29 adds several compiler warnings by default and removes 32-bit Windows builds, while also noting that obsolete guard tests will be removed in Erlang/OTP 30.