# Crystalline - LSP server for Crystal **URL:** \ **Category:** Community\ **Created:** [September 19, 2020, 10:12am UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535 "2020-09-19T10:12:54Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![elbywan](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.crystal-lang.org/elbywan/32/762_2.png) [@elbywan](https://forum.crystal-lang.org/u/elbywan)\ **Post date:** [September 19, 2020, 10:12am UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/1 "2020-09-19T10:12:54Z")
Hi everyone šŸ‘‹ , I am currently writing [`Crystalline`](https://github.com/elbywan/crystalline), a Language Server Protocol implementation (think Scry) for Crystal that provides **limited** language features (like go-to, autocompletion, syntax and semantic checking). Iā€™m still working on it, and Iā€™m planning to improve some parts of it. I began using it for my own projects for a few days now and I find it quite helpful, so Iā€™m sharing it here in case people were missing these IDE features a much as I did šŸ™‚. Small disclaimer: `Crystalline` does not aim to be as fast - or as feature complete - as other LSP because it would involve a massive amount of effort to write incremental semantic analysis, a fault tolerant parser or other tools needed. Despite that it should be in a fairly stable state - meaning it should not crash or report wrong information. But do not expect it to work in all cases, it will not report anything when type information is missing. ---
**Author:** ![Acciaiodigitale](https://avatars.discourse-cdn.com/v4/letter/a/74df32/32.png) [@Acciaiodigitale](https://forum.crystal-lang.org/u/Acciaiodigitale)\ **Post date:** [September 19, 2020, 10:31am UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/2 "2020-09-19T10:31:09Z")
I just updated [VS Code plugin](https://marketplace.visualstudio.com/items?itemName=crystal-lang-tools.crystal-lang) with the updated dependencies to work with [Crystalline](https://github.com/elbywan/crystalline). I hope we can include Crystalline to crystal-lang-tools organisation if you @elbywan want and other organisation members agree (@bcardiff?) ---
**Author:** ![sol.vin](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.crystal-lang.org/sol.vin/32/73_2.png) [@sol.vin](https://forum.crystal-lang.org/u/sol.vin)\ **Post date:** [September 19, 2020, 11:48am UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/3 "2020-09-19T11:48:20Z")
I tried compiling it but it never produced a binary or any meaningful error. Just saysā€¦ ` ian@computer:~/Downloads/crystalline$ sudo crystal build ./src/crystalline.cr -o ./bin/crystalline --release --no-debug --progress -Dpreview_mt Killed] [0/1] Codegen (bc+obj) ` ---
**Author:** ![Acciaiodigitale](https://avatars.discourse-cdn.com/v4/letter/a/74df32/32.png) [@Acciaiodigitale](https://forum.crystal-lang.org/u/Acciaiodigitale)\ **Post date:** [September 19, 2020, 11:58am UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/4 "2020-09-19T11:58:09Z")
Iā€™m on a Mac. I have a problem with llvm and libxml2. @elbywan can you help @sol.vin? Have you experience with Windows? ---
**Author:** ![asterite](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.crystal-lang.org/asterite/32/60_2.png) [@asterite](https://forum.crystal-lang.org/u/asterite)\ **Post date:** [September 19, 2020, 12:01pm UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/5 "2020-09-19T12:01:56Z")
This is great! Could you give a high level overview of how it works? For example what happens when you ask for autocompletion. ---
**Author:** ![elbywan](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.crystal-lang.org/elbywan/32/762_2.png) [@elbywan](https://forum.crystal-lang.org/u/elbywan)\ **Post date:** [September 19, 2020, 12:13pm UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/6 "2020-09-19T12:13:03Z")
> [@Acciaiodigitale](#): > > I hope we can include Crystalline to crystal-lang-tools organisation if you @elbywan want and other organisation members agree (@bcardiff?) Iā€™m wondering if it would not be a bit too soon, I would rather wait to see if other people find it useful. It also lacks **a lot** of polish (incoplete features, no binaries or brew install, undocumented code, no specs). > [@Acciaiodigitale](#): > > Iā€™m on a Mac. I have a problem with llvm and libxml2. These are crystal compiler dependencies, which `Crystalline` uses under the hood. Regarding LLVM, can you check [these instructions](https://github.com/elbywan/crystalline#llvm-config)? For libxml, there is a llvm 10 bug on macos when checking system dependencies. ```auto āÆ llvm-config --system-libs 14:05:22 -lm -lz -lcurses -llibxml2.tbd ``` (`-llibxml2.tbd` is wrong) A workaround is to add a symbolic link: `ln -s /usr/lib/libxml2.2.dylib /usr/local/lib/liblibxml2.tbd.dylib` It is not ideal, but until llvm produces a fix Iā€™m afraid this is required. More info [here](https://github.com/ziglang/zig/issues/6087). > [@sol.vin](#): > > I tried compiling it but it never produced a binary or any meaningful error. Just saysā€¦ Well sorry I cannot give more insight on that issue, but as `Crystalline` embarks the crystal compiler it does require a **large** amount of RAM to compile, and **it takes a while**. `Killed] [0/1] Codegen (bc+obj)` Did you kill it yourself? Because if so, it looks like it was still compiling. In all cases, Iā€™m planning to provide compiled binaries in the future. > [@Acciaiodigitale](#): > > Have you experience with Windows? Hmm sorry no, Iā€™m not a Window user (except for playing games šŸŽ®). ---
**Author:** ![elbywan](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.crystal-lang.org/elbywan/32/762_2.png) [@elbywan](https://forum.crystal-lang.org/u/elbywan)\ **Post date:** [September 19, 2020, 12:20pm UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/7 "2020-09-19T12:20:19Z")
> [@asterite](#): > > Could you give a high level overview of how it works? For example what happens when you ask for autocompletion. Well it is quite simple actually. Iā€™m mostly relying on what you guys did already, the Crystal parser & semantic analysis to produce a typed AST and I extract meaningful information using visitors to display that in the editor. Of course, I try to cache the result as most as possible - when possible, and be a bit clever on how to process requests in parallel, in threads isolated from the language server I/O loop and use some locks to not overload the server. For instance it will not trigger a full scale analysis when you just hover or go to a definition every time. It will just reuse the last analysis result. It will also not run 15 compiler tasks at the same time if you ask for autocompletion 15 times after typing a character, it will wait for the pending analysis to complete and run another one afterwards to process the latest updates. And it will not block in the meantime if the user just wants to use the formatter. There really is a lot of room for improvements, but for small to medium scale projects with a decent computer it seems to be working fine for me. I donā€™t have a lot of spare time unfortunately these days, so I wonā€™t be able to write down more than that. The first step would be to document the code and refine the features. ---
**Author:** ![Acciaiodigitale](https://avatars.discourse-cdn.com/v4/letter/a/74df32/32.png) [@Acciaiodigitale](https://forum.crystal-lang.org/u/Acciaiodigitale)\ **Post date:** [September 19, 2020, 12:43pm UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/8 "2020-09-19T12:43:06Z")
Worked for me. Thanks. ---
**Author:** ![hugopl](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.crystal-lang.org/hugopl/32/970_2.png) [@hugopl](https://forum.crystal-lang.org/u/hugopl)\ **Post date:** [September 21, 2020, 11:17pm UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/9 "2020-09-21T23:17:22Z")
Hi, Have you interest in using [https://github.com/crystal-lang-tools/lsp](https://github.com/crystal-lang-tools/lsp) ? if so, me too, as this repository seems dead, I keep a fork on [https://github.com/hugopl/lsp](https://github.com/hugopl/lsp) with my patchesā€¦ and Iā€™m using it to write a LSP client for an editor, Tijolo. ---
**Author:** ![elbywan](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.crystal-lang.org/elbywan/32/762_2.png) [@elbywan](https://forum.crystal-lang.org/u/elbywan)\ **Post date:** [September 22, 2020, 5:36am UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/10 "2020-09-22T05:36:01Z")
Hey @hugopl, > [@hugopl](#): > > Have you interest in using [https://github.com/crystal-lang-tools/lsp](https://github.com/crystal-lang-tools/lsp) ? I tried using it at first but I had issues because: - it was relying on an old version of the standard - some json structures conflict when deserializing - there is only type definitions in the shard - I needed an up-to-date server So for `Crystalline` I wrote the LSP part from scratch alongside a generic server loop implementation. I was planning to extract this part as a shard but as I implemented only the messages I needed and skipped specs so weā€™ll see in the future! ---
**Author:** ![nico](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.crystal-lang.org/nico/32/692_2.png) [@nico](https://forum.crystal-lang.org/u/nico)\ **Post date:** [September 22, 2020, 11:09am UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/11 "2020-09-22T11:09:58Z")
Oh thank you! Itā€™s great! It is better to uninstall Scry or Crystalline comes as a complement? ---
**Author:** ![pfischer](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.crystal-lang.org/pfischer/32/330_2.png) [@pfischer](https://forum.crystal-lang.org/u/pfischer)\ **Post date:** [September 22, 2020, 11:23am UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/12 "2020-09-22T11:23:06Z")
Awesome! šŸ‘ Just write in the README that LLVM 8 is needed (it is not possible to compile with LLVM 10). ---
**Author:** ![elbywan](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.crystal-lang.org/elbywan/32/762_2.png) [@elbywan](https://forum.crystal-lang.org/u/elbywan)\ **Post date:** [September 22, 2020, 11:46am UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/13 "2020-09-22T11:46:15Z")
> [@nico](#): > > Oh thank you! Itā€™s great! Thanks! šŸ˜„ > [@nico](#): > > It is better to uninstall Scry or Crystalline comes as a complement? Itā€™s either one or the other. ---
**Author:** ![elbywan](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.crystal-lang.org/elbywan/32/762_2.png) [@elbywan](https://forum.crystal-lang.org/u/elbywan)\ **Post date:** [September 22, 2020, 11:52am UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/14 "2020-09-22T11:52:34Z")
> [@pfischer](#): > > Awesome! Thanks! šŸ‘ > [@pfischer](#): > > Just write in the README that LLVM 8 is needed (it is not possible to compile with LLVM 10). I donā€™t really know about other OSes, but on macos it is technically possible to compile with LLVM10 even though there is a bug in the current minor version. I posted the workaround earlier: > [@elbywan](#): > > For libxml, there is a llvm 10 bug on macos when checking system dependencies. > > ```auto > āÆ llvm-config --system-libs 14:05:22 > -lm -lz -lcurses -llibxml2.tbd > > ``` > > ( `-llibxml2.tbd` is wrong) > > A workaround is to add a symbolic link: > > `ln -s /usr/lib/libxml2.2.dylib /usr/local/lib/liblibxml2.tbd.dylib` > > It is not ideal, but until llvm produces a fix Iā€™m afraid this is required. > More info [here](https://github.com/ziglang/zig/issues/6087). It is not obvious though, and youā€™re right to highlight the fact that I should definitely write something in the readme šŸ˜‰. ---
**Author:** ![nico](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.crystal-lang.org/nico/32/692_2.png) [@nico](https://forum.crystal-lang.org/u/nico)\ **Post date:** [September 22, 2020, 12:37pm UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/15 "2020-09-22T12:37:19Z")
> [@elbywan](#): > > Itā€™s either one or the other. OK thanks ---
**Author:** ![hugopl](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.crystal-lang.org/hugopl/32/970_2.png) [@hugopl](https://forum.crystal-lang.org/u/hugopl)\ **Post date:** [September 22, 2020, 2:02pm UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/16 "2020-09-22T14:02:42Z")
> [@elbywan](#): > > - it was relying on an old version of the standard > - some json structures conflict when deserializing > - there is only type definitions in the shard - I needed an up-to-date server Yep, Iā€™m aware of the first two issues you said, the third one isnā€™t really an issue because the shard idea is to have only the type definitions decoupled from any client/server implementationā€¦ to avoid the boring task of replicating them from the specā€¦ Iā€™m using it because it saved some of my time and as I use only a tiny part of LSP, the structures conflicts arenā€™t a problem (yet) for me. I saw you use partial text-sync on Crystaline, this is very goodā€¦ scry uses full text sync, i.e. ask the client to send the whole file on every change, something really slow and non-sense. ---
**Author:** ![elbywan](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.crystal-lang.org/elbywan/32/762_2.png) [@elbywan](https://forum.crystal-lang.org/u/elbywan)\ **Post date:** [September 22, 2020, 2:51pm UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/17 "2020-09-22T14:51:36Z")
> [@hugopl](#): > > the third one isnā€™t really an issue because the shard idea is to have only the type definitions decoupled from any client/server implementationā€¦ to avoid the boring task of replicating them from the specā€¦ Yes I understand the idea, and I was actually not talking about a full server implementation. That was a bit obscure, but when I was talking about ā€œserverā€ I was referring to a class orchestrating the whole protocol (requests / notifications / responses / replies / errors), dispatching the messages to an external entity in a non blocking way when needed and replying to clients. So basically the I/O loop, but without any concrete action taken when a message is processed. The actual implementation could then be delegated to a controller class separate from the shard. This is what I [tried to do](https://github.com/elbywan/crystalline/blob/master/src/crystalline/lsp/server.cr) in the `/lsp` part of `Crystalline`. ---
**Author:** ![nico](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.crystal-lang.org/nico/32/692_2.png) [@nico](https://forum.crystal-lang.org/u/nico)\ **Post date:** [September 22, 2020, 4:26pm UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/18 "2020-09-22T16:26:42Z")
Install on Ubuntu 18.04 (WIP). Itā€™s safer to use the same (or closest) LLVM version that Crystal compiler. When writing this message: ```auto crystal version Crystal 0.35.1 [5999ae29b] (2020-06-19) LLVM: 8.0.0 Default target: x86_64-unknown-linux-gnu ``` So LLVM 8 (but the ./llvm.sh official script support v9 and +, I have a compil error) ```bash git clone https://github.com/elbywan/crystalline cd ./crystalline # Install llvm sudo apt-get update wget https://apt.llvm.org/llvm.sh chmod +x llvm.sh sudo ./llvm.sh 9 # whereis llvm-config-9 (v9 for me), when located add the path to env export LLVM_CONFIG=/usr/bin/llvm-config-9 # build Crystalline mkdir ./bin crystal build ./src/crystalline.cr -o ./bin/crystalline --release --no-debug --progress -Dpreview_mt ``` Then make it executable `chmod +x crystalline`, then add crystalline to a bin path (executable), like `mv ./crystalline $HOME/bin/crystalline` or /usr/local/bin or /usr/bin > But I have [an error during the Crystalline build](https://github.com/elbywan/crystalline/issues/1). I will test again on the next Crystal version. ---
**Author:** ![bew](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.crystal-lang.org/bew/32/113_2.png) [@bew](https://forum.crystal-lang.org/u/bew)\ **Post date:** [September 22, 2020, 4:42pm UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/19 "2020-09-22T16:42:38Z")
Hello! This project is a very good news! As a contributor on scry (for various reasons I stopped doing crystal for now thoughā€¦) youā€™re doing it right! Iā€™m happy that someone is taking over this subject that way!! ---
**Author:** ![asterite](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.crystal-lang.org/asterite/32/60_2.png) [@asterite](https://forum.crystal-lang.org/u/asterite)\ **Post date:** [September 23, 2020, 7:24pm UTC](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535/20 "2020-09-23T19:24:48Z")
I wonder if crystalline could be renamed to something elseā€¦ just because of the fact that now that I have it in my path, autocompleting `crys` stops at `crystal` without a space, where previously it was the only binary I had matching that. Is it needed to put crystalline in the path at all if itā€™s needed to be configured in vscode? [Next page](https://forum.crystal-lang.org/t/crystalline-lsp-server-for-crystal/2535.md?page=2)