# Help & Support **URL:** https://forum.crystal-lang.org/c/help-support/11.md [Latest](https://forum.crystal-lang.org/latest.md) · [Categories](https://forum.crystal-lang.org/categories.md) · [Tags](https://forum.crystal-lang.org/tags.md) --- ## [About the Help & Support category](https://forum.crystal-lang.org/t/about-the-help-support-category/25)
**Author:** [@bcardiff](https://forum.crystal-lang.org/u/bcardiff)\ **Replies:** 0
Finding troubles along the way, or not finding how to do something? Feel free to express any kind of doubt. --- ## [Just for confirm: after the discussions, what do people (including the core team) call someone who uses Crystal?](https://forum.crystal-lang.org/t/just-for-confirm-after-the-discussions-what-do-people-including-the-core-team-call-someone-who-uses-crystal/9208)
**Author:** [@zw963](https://forum.crystal-lang.org/u/zw963)\ **Replies:** 4\ **Last updated:** [October 13, 2026, 4:03am UTC](https://forum.crystal-lang.org/t/just-for-confirm-after-the-discussions-what-do-people-including-the-core-team-call-someone-who-uses-crystal/9208 "2026-10-13T04:03:52Z")
I want to add a default name for my crystal-china forum; User????? feels not good. As Rubyist for Ruby, which is the prefer name for Crystal? --- ## [Alternatives To Snake Case? \[ String Splitting, Parsing \]](https://forum.crystal-lang.org/t/alternatives-to-snake-case-string-splitting-parsing/9169)
**Author:** [@LWFlouisa](https://forum.crystal-lang.org/u/LWFlouisa)\ **Replies:** 4\ **Last updated:** [October 13, 2026, 3:18am UTC](https://forum.crystal-lang.org/t/alternatives-to-snake-case-string-splitting-parsing/9169 "2026-10-13T03:18:09Z")
Background Before I go into the particular error I’m encountering, it’s worth mentioning how I got here: I was trying to make a scripting language in Ruby, because I was originally game developing in that language. But… --- ## [Generic class new doesn't infer type var for instance var](https://forum.crystal-lang.org/t/generic-class-new-doesnt-infer-type-var-for-instance-var/9203)
**Author:** [@2f1cafc](https://forum.crystal-lang.org/u/2f1cafc)\ **Replies:** 2\ **Last updated:** [October 11, 2026, 8:10am UTC](https://forum.crystal-lang.org/t/generic-class-new-doesnt-infer-type-var-for-instance-var/9203 "2026-10-11T08:10:29Z")
Hi all, When Foo is defined like this: class Foo(T) def initialize(@value : T); end end the following works fine as a local var, which matches the description in the Generics section of the spec: x = Foo.new("hello")… --- ## [Ld64.lld: undefined symbol: close (and memcpy/memset/etc.) linking on macOS 26 (Xcode 26.2 SDK)](https://forum.crystal-lang.org/t/ld64-lld-undefined-symbol-close-and-memcpy-memset-etc-linking-on-macos-26-xcode-26-2-sdk/9157)
**Author:** [@chikega](https://forum.crystal-lang.org/u/chikega)\ **Replies:** 1\ **Last updated:** [October 9, 2026, 10:27am UTC](https://forum.crystal-lang.org/t/ld64-lld-undefined-symbol-close-and-memcpy-memset-etc-linking-on-macos-26-xcode-26-2-sdk/9157 "2026-10-09T10:27:04Z")
Since updating to macOS 26.6.2 with Xcode 26.2, Crystal fails to link any program — even a trivial puts "hello" — with undefined symbol errors for basic libc functions. Environment crystal --version Crystal 1.21.0 (202… --- ## [Runtime problem with an application compiled with Crystal 1.21.1](https://forum.crystal-lang.org/t/runtime-problem-with-an-application-compiled-with-crystal-1-21-1/9183)
**Author:** [@MarioAriasC](https://forum.crystal-lang.org/u/MarioAriasC)\ **Replies:** 5\ **Last updated:** [October 4, 2026, 7:00pm UTC](https://forum.crystal-lang.org/t/runtime-problem-with-an-application-compiled-with-crystal-1-21-1/9183 "2026-10-04T19:00:32Z")
Hi there, The application compiles fine, but it fails when I try to run it. System info: MBP 2026 with M5 processor Crystal installed through MacPorts When I compiled the application with -Dwithout\_mt I see this err… --- ## [GitHub action for Ubuntu GETting 404 fetching dependencies](https://forum.crystal-lang.org/t/github-action-for-ubuntu-getting-404-fetching-dependencies/9178)
**Author:** [@nogginly](https://forum.crystal-lang.org/u/nogginly)\ **Replies:** 8\ **Last updated:** [October 4, 2026, 12:48am UTC](https://forum.crystal-lang.org/t/github-action-for-ubuntu-getting-404-fetching-dependencies/9178 "2026-10-04T00:48:18Z")
UPDATE: I have a workaround! See end of topic. Is anyone else seeing this? I tried searching the web but my search fu isn’t strong apparently. - { os: ubuntu-latest, crystal: "1.20" } - { os: ubun… --- ## [Socket connection error after macOS 26.7 update](https://forum.crystal-lang.org/t/socket-connection-error-after-macos-26-7-update/9145)
**Author:** [@nogginly](https://forum.crystal-lang.org/u/nogginly)\ **Replies:** 10\ **Last updated:** [September 27, 2026, 5:49pm UTC](https://forum.crystal-lang.org/t/socket-connection-error-after-macos-26-7-update/9145 "2026-09-27T17:49:04Z")
UPDATE 2026-09-18 - Script connect\_refusal\_check\_v2.cr replaces earlier version below, adding a test without O\_NONBLOCK, which turned out to be OK (whew!) Hola folks, I’m looking for folks who are running macOS and h… --- ## [Variables in loops](https://forum.crystal-lang.org/t/variables-in-loops/9163)
**Author:** [@Carlos](https://forum.crystal-lang.org/u/Carlos)\ **Replies:** 1\ **Last updated:** [September 22, 2026, 8:17pm UTC](https://forum.crystal-lang.org/t/variables-in-loops/9163 "2026-09-22T20:17:52Z")
Take a look at the silly example: 2.times do |i| x = uninitialized Int32 if x == 50 puts "x = 50, i = #{i}" puts " (by chance!)" if i == 0 end x = 50 end Is x created anew on each iteration, and by chan… --- ## [Help with the Log module and databases](https://forum.crystal-lang.org/t/help-with-the-log-module-and-databases/9158)
**Author:** [@GalactHD](https://forum.crystal-lang.org/u/GalactHD)\ **Replies:** 4\ **Last updated:** [September 20, 2026, 12:05pm UTC](https://forum.crystal-lang.org/t/help-with-the-log-module-and-databases/9158 "2026-09-20T12:05:11Z")
Hi! Is it possible to use the Log module to get logs about queries/database access? Something like the Active Record logs, but only using the crystal-pg driver. --- ## [How about the new lightwight semantic analyzer in newest 0.19 crystalline?](https://forum.crystal-lang.org/t/how-about-the-new-lightwight-semantic-analyzer-in-newest-0-19-crystalline/9125)
**Author:** [@zw963](https://forum.crystal-lang.org/u/zw963)\ **Replies:** 6\ **Last updated:** [September 18, 2026, 3:23pm UTC](https://forum.crystal-lang.org/t/how-about-the-new-lightwight-semantic-analyzer-in-newest-0-19-crystalline/9125 "2026-09-18T15:23:12Z")
I am compiling, although, I’m not use LSP server too often. AI told me, current model is eventually-refined semantic model. What do you think? has the speed increased? better experience? --- ## [Not initialized error](https://forum.crystal-lang.org/t/not-initialized-error/9139)
**Author:** [@1004w](https://forum.crystal-lang.org/u/1004w)\ **Replies:** 13\ **Last updated:** [September 15, 2026, 7:28pm UTC](https://forum.crystal-lang.org/t/not-initialized-error/9139 "2026-09-15T19:28:11Z")
the code is: # units.cr require "./gamedata" require "./supports/macros" require "./modules" require "sdl" require "./lib/sdl/src/image" require "./lib/sdl/src/mix" require "./lib/sdl/src/ttf" require "./buildings" requ… --- ## [Crystal JSON Lexer is too strict on single unpaired UTF-16 surrogate for skipped fields](https://forum.crystal-lang.org/t/crystal-json-lexer-is-too-strict-on-single-unpaired-utf-16-surrogate-for-skipped-fields/9138)
**Author:** [@dammer](https://forum.crystal-lang.org/u/dammer)\ **Replies:** 2\ **Last updated:** [September 9, 2026, 3:16pm UTC](https://forum.crystal-lang.org/t/crystal-json-lexer-is-too-strict-on-single-unpaired-utf-16-surrogate-for-skipped-fields/9138 "2026-09-09T15:16:32Z")
A little code sample: require "json" # raw JSON frame with a lone-surrogate ESCAPE (not raw invalid bytes) raw = %q({"post\_data":"before\\uda41after","x":1}) puts "raw valid\_encoding? #{raw.valid\_encoding?}" struct … --- ## [Using new parallel ExecutionContext](https://forum.crystal-lang.org/t/using-new-parallel-executioncontext/9069)
**Author:** [@jzakiya](https://forum.crystal-lang.org/u/jzakiya)\ **Replies:** 26\ **Last updated:** [September 3, 2026, 9:56pm UTC](https://forum.crystal-lang.org/t/using-new-parallel-executioncontext/9069 "2026-09-03T21:56:00Z")
I converted my residue sieves to use the new Crystal 1.21 ExecutionContext structures. They’re a significant upgrade in convenience, flexibility, and performance to create true parallelism. :slight\_smile: Under the old… --- ## [How to make your crystal program compile reeeeeally slow](https://forum.crystal-lang.org/t/how-to-make-your-crystal-program-compile-reeeeeally-slow/9130)
**Author:** [@ralsina](https://forum.crystal-lang.org/u/ralsina)\ **Replies:** 10\ **Last updated:** [September 3, 2026, 11:52am UTC](https://forum.crystal-lang.org/t/how-to-make-your-crystal-program-compile-reeeeeally-slow/9130 "2026-09-03T11:52:10Z")
Here is a pretty innocent program that takes a really long time to compile if you use --release: # big.cr — a def that returns a ~163KB struct by value struct Big getter a : StaticArray(UInt64, 20410) # 20410 \* 8 = ~1… --- ## [How to create a GUI app using libui-ng on Windows?](https://forum.crystal-lang.org/t/how-to-create-a-gui-app-using-libui-ng-on-windows/6361)
**Author:** [@kojix2](https://forum.crystal-lang.org/u/kojix2)\ **Replies:** 36\ **Last updated:** [August 30, 2026, 7:35am UTC](https://forum.crystal-lang.org/t/how-to-create-a-gui-app-using-libui-ng-on-windows/6361 "2026-08-30T07:35:28Z")
Hi I heard that Windows support has been improved in Crystal 1.11. Can someone tell me how to create a GUI app using libui-ng and libui.cr? Are static libraries sufficient instead of shared libraries on Windows? http… --- ## [Surprising non-performance of String#split](https://forum.crystal-lang.org/t/surprising-non-performance-of-string-split/9113)
**Author:** [@Xen](https://forum.crystal-lang.org/u/Xen)\ **Replies:** 16\ **Last updated:** [August 28, 2026, 9:45am UTC](https://forum.crystal-lang.org/t/surprising-non-performance-of-string-split/9113 "2026-08-28T09:45:12Z")
So I was hacking together a tool to chew through a CSV file and was considering performance as I’ll have to process something in the vicinity of 11 million rows. So I was playing around with a simple script to figure out… --- ## [Log: When to use emit vs. context](https://forum.crystal-lang.org/t/log-when-to-use-emit-vs-context/9022)
**Author:** [@phil294](https://forum.crystal-lang.org/u/phil294)\ **Replies:** 3\ **Last updated:** [August 9, 2026, 6:07am UTC](https://forum.crystal-lang.org/t/log-when-to-use-emit-vs-context/9022 "2026-08-09T06:07:24Z")
Hello, when do you use one over the other? I can’t really find docs about this. The following just prints both data structures, making me wonder why there are two different ways of doing it. The only difference I can se… --- ## [Redis sentinel support](https://forum.crystal-lang.org/t/redis-sentinel-support/9071)
**Author:** [@dup2](https://forum.crystal-lang.org/u/dup2)\ **Replies:** 7\ **Last updated:** [July 29, 2026, 11:22am UTC](https://forum.crystal-lang.org/t/redis-sentinel-support/9071 "2026-07-29T11:22:39Z")
We are looking for a way to use the redis sentinel setup for an application written in crystal but could not find any maintained shard for this. The only implementation we found is GitHub - pgeraghty/redis-sentinel-crys… --- ## [Unexpected token: "DELIMITER\_START" was, well, unexpected](https://forum.crystal-lang.org/t/unexpected-token-delimiter-start-was-well-unexpected/9070)
**Author:** [@swsch](https://forum.crystal-lang.org/u/swsch)\ **Replies:** 3\ **Last updated:** [July 24, 2026, 2:54pm UTC](https://forum.crystal-lang.org/t/unexpected-token-delimiter-start-was-well-unexpected/9070 "2026-07-24T14:54:45Z")
I was doing some warmup exercises and ran into some unexpected behaviour. The original code and its inlined version def bday\_pdox(n : Int32) : Float64 diff = (365 - n + 1..365).product all = 365\*\*n 1 - diff… --- ## [How to enable automatic multi-thread on Crystal 1.21?](https://forum.crystal-lang.org/t/how-to-enable-automatic-multi-thread-on-crystal-1-21/9065)
**Author:** [@zw963](https://forum.crystal-lang.org/u/zw963)\ **Replies:** 4\ **Last updated:** [July 18, 2026, 10:17am UTC](https://forum.crystal-lang.org/t/how-to-enable-automatic-multi-thread-on-crystal-1-21/9065 "2026-07-18T10:17:59Z")
AFAIK, for avoids breaking change to existing applications that may not be ready for MT, if we want a Crystal application use maximum multi-core, we need added following source code manually. Fiber::ExecutionContext.de… --- ## [Non-blocking STDIN read](https://forum.crystal-lang.org/t/non-blocking-stdin-read/9061)
**Author:** [@kostya](https://forum.crystal-lang.org/u/kostya)\ **Replies:** 3\ **Last updated:** [July 14, 2026, 9:43am UTC](https://forum.crystal-lang.org/t/non-blocking-stdin-read/9061 "2026-07-14T09:43:44Z")
I doing this: unless STDIN.tty? content = STDIN.gets\_to\_end end when there is no stdin, this works in terminal, but stale when running in docker compose run - because docker not close stdin. if I do something like… --- ## [Clear-cache effect?](https://forum.crystal-lang.org/t/clear-cache-effect/9028)
**Author:** [@hutou](https://forum.crystal-lang.org/u/hutou)\ **Replies:** 1\ **Last updated:** [June 25, 2026, 4:34pm UTC](https://forum.crystal-lang.org/t/clear-cache-effect/9028 "2026-06-25T16:34:42Z")
Can the ‘crystal clear\_cache’ command have a (very) significant impact on the size of the executable (and the compile time)? --- ## [Compilation on OpenBSD](https://forum.crystal-lang.org/t/compilation-on-openbsd/9019)
**Author:** [@karchnu](https://forum.crystal-lang.org/u/karchnu)\ **Replies:** 11\ **Last updated:** [June 22, 2026, 1:20pm UTC](https://forum.crystal-lang.org/t/compilation-on-openbsd/9019 "2026-06-22T13:20:19Z")
Hello, I’ve tried to compile my project on Linux and it works great, however I have problems on OpenBSD. The default crypto library is LibreSSL and I had to use pkg\_add openssl to install OpenSSL. Fine. Now, I try to … --- ## [State & Plans of GUI development with Crystal](https://forum.crystal-lang.org/t/state-plans-of-gui-development-with-crystal/1615)
**Author:** [@blkstph](https://forum.crystal-lang.org/u/blkstph)\ **Replies:** 79\ **Last updated:** [June 16, 2026, 7:31am UTC](https://forum.crystal-lang.org/t/state-plans-of-gui-development-with-crystal/1615 "2026-06-16T07:31:23Z")
I did a quick search for “GUI development in Crystal” and got back some dated references to “Shards” and “Amber” web application framework. While I am well aware that enterprise development for desktop is not the curren… --- ## [User-space pipe implementation](https://forum.crystal-lang.org/t/user-space-pipe-implementation/8837)
**Author:** [@jgaskins](https://forum.crystal-lang.org/u/jgaskins)\ **Replies:** 40\ **Last updated:** [June 15, 2026, 6:59am UTC](https://forum.crystal-lang.org/t/user-space-pipe-implementation/8837 "2026-06-15T06:59:44Z")
A couple months ago I wrote a shard that works like IO.pipe but lives entirely in user-space. That is, it does not involve syscalls at all. The shard is called pipe: Two reasons this is noteworthy: IO.pipe returns f… --- ## [Macro finished](https://forum.crystal-lang.org/t/macro-finished/8966)
**Author:** [@Xen](https://forum.crystal-lang.org/u/Xen)\ **Replies:** 9\ **Last updated:** [June 2, 2026, 6:56pm UTC](https://forum.crystal-lang.org/t/macro-finished/8966 "2026-06-02T18:56:24Z")
I had a discussion with Gemini about how things ought to work. It revolved around using the finished macro to add code to register classes. But it didn’t work (the exact case can be fixed with included, but that’s anoth… --- ## [Argon2 question](https://forum.crystal-lang.org/t/argon2-question/8959)
**Author:** [@BloodFeastMan](https://forum.crystal-lang.org/u/BloodFeastMan)\ **Replies:** 1\ **Last updated:** [May 30, 2026, 12:38pm UTC](https://forum.crystal-lang.org/t/argon2-question/8959 "2026-05-30T12:38:11Z")
Has anyone successfully used sushichain/crystal-argon2 with Windows? I know it’s quite old, but I have a small CLI that built just fine at home (Debian) but here on a Windows 11 device doesn’t work, here’s the output, m… --- ## [ERROR: Unable to identify distribution type (void)](https://forum.crystal-lang.org/t/error-unable-to-identify-distribution-type-void/8946)
**Author:** [@Quin](https://forum.crystal-lang.org/u/Quin)\ **Replies:** 8\ **Last updated:** [May 22, 2026, 5:38am UTC](https://forum.crystal-lang.org/t/error-unable-to-identify-distribution-type-void/8946 "2026-05-22T05:38:26Z")
I’m attempting to install Crystal on Void Linux, but always get the following error: quin@Minix~$ curl -fsSL https://crystal-lang.org/install.sh | sudo bash Password: ERROR: Unable to identify distribution type (void)… --- ## [Why my shards no search result in shardbox or shards.info?](https://forum.crystal-lang.org/t/why-my-shards-no-search-result-in-shardbox-or-shards-info/8934)
**Author:** [@zw963](https://forum.crystal-lang.org/u/zw963)\ **Replies:** 11\ **Last updated:** [May 13, 2026, 8:09am UTC](https://forum.crystal-lang.org/t/why-my-shards-no-search-result-in-shardbox-or-shards-info/8934 "2026-05-13T08:09:41Z")
I have this question after I saw the 5 Years Anniversary video, Because of the decentralized nature of Crystal shards, I don’t actually use them very often. However, I am curious just as an example, why my shards, such a… [Next page](https://forum.crystal-lang.org/c/help-support/11.md?page=1)