| 13 Mar 2026 |
 ijouw | I have multiple haskellPackages.developPackage projects i develop infrequently (it's ok if build fails sometimes) using cabal.
I use import <nixpkgs> {} because i do not want to manually set versions for their ghc toolchain, and have them all use the same compiler (they should update using a centrally defined value ; i used ghcup before and it installed 200gb of ghc and libs in a year). I now want to test a newer version of ghc (i want to test the haskell debugger project) but my stable nixpkgs only has ghcHEAD with version >= 9.14 (but which appears to be not yet supported by cabal (or is the cabal in my ghcHEAD an old one?)). Is there a way to have similar behavior?
I was thinking of copying haskell.packages.ghc___ from unstable into my local nixpkgs or pinning unstable in a central haskell project that i need to pull from manually. Any advice is welcome. | 23:11:58 |
 alexfmpe | I have a "devenv" project with basically just a shell.nix with a nixpkgs pin and haskell tooling | 23:35:01 |
| alexfmpe | that way it's independent of my system nixpkgs, yet it works as a default environment for all projects where I cba doing anything fancier than <nixpkgs> | 23:35:47 |
| alexfmpe | if you really want a nixpkgs-provisioned debugger, you probably want to point to haskell-updates branch, as https://github.com/NixOS/nixpkgs/pull/496489 is fairly recent and not yet in unstable branch | 23:38:09 |
| alexfmpe | * I have a "devenv" project with basically just a shell.nix with a nixpkgs pin for haskell tooling | 23:38:30 |
| alexfmpe |
or pinning unstable in a central haskell project that i need to pull from manually.
so I guess this, but pin current haskell-updates
| 23:40:08 |
| alexfmpe | also much better for caching than import <nixpkgs> or nix-shell -p cabal-install ghc ghcid | 23:41:00 |
| ijouw | Is there a binary cache? (Currently building some libraries i know i do not depend on in my project). | 23:58:45 |
| 14 Mar 2026 |
| ijouw | 🤔 Maybe i should try it with a minimal project, since nix-shell failed. | 00:01:21 |
| alexfmpe | $ git checkout haskell-updates && git pull && git rev-parse HEAD
56381786faa2041f516ff01763773aeb74a45542
$ uname -mo
x86_64 GNU/Linux
$ nix-build -A haskell.packages.ghc914.haskell-debugger --dry-run
these 18 paths will be fetched (32.69 MiB download, 288.83 MiB unpacked):
/nix/store/mzs5rrq8qwm7dy98lmy056fds8y1ywlr-aeson-pretty-0.8.10
/nix/store/5pc3b8plrddq2d20zsqf36n50pd59wbp-aeson-pretty-0.8.10-doc
/nix/store/bkksvi9rw9jfd298yib647qhlw15ai6v-attoparsec-0.14.4
/nix/store/kdagha0cwzgp5vs3rv621ln5yp9nsaf9-attoparsec-aeson-2.2.2.0
/nix/store/gr680f8n9mpxw6g1hxgkj8s57cwddkdy-attoparsec-aeson-2.2.2.0-doc
/nix/store/ckj58hgwzp6nwyglm4p9v828mw5jf7lb-conduit-extra-1.3.8
/nix/store/mcsl8ad89px6ai3l1rbywwl254h59qms-conduit-extra-1.3.8-doc
/nix/store/xlywz2jsnx46c4b26zjimy4pvj803i7x-dap-0.4.0.0
/nix/store/yw0kb5wskw99cw9jav1i1c4bml0f7csr-dap-0.4.0.0-doc
/nix/store/n68wbiwivj566m2vs9lf6hz6ymz0k89l-haskell-debugger-0.12.1.0
/nix/store/p5wd0gnlwgd86rv1laxz0lzsrv0nc0vk-haskell-debugger-0.12.1.0-doc
/nix/store/1s5igrda049qc2b5ygz2kiscl2d2in88-hie-bios-0.18.0
/nix/store/vs1v8lj5spa46hggfxgfpxgh8qsn96rb-hie-bios-0.18.0-doc
/nix/store/c9jm879c940a2jridcw74b86l7qwpgmx-implicit-hie-0.1.4.0
/nix/store/qw6ydf2ydm32l0ah5m9abq1c252wia5f-implicit-hie-0.1.4.0-doc
/nix/store/rqmrlc2jz7vh551fs8r4w4k61v8q8p01-yaml-0.11.11.2
/nix/store/kv1wvvb9vr8qlcvh07rz4h86pxa4khkg-yaml-0.11.11.2-bin
/nix/store/ljqjkyfi0bg4xxqfqdbdx4qx7qkky9am-yaml-0.11.11.2-doc
| 00:02:10 |
| alexfmpe | you might be building some transitive deps, or deps of tooling (e.g. cabal-install, cabal2nix) | 00:03:01 |
| ijouw | It started building basement foundation and happy (it likely was compiling cabal and hoogle ) | 00:03:21 |
| alexfmpe | I think there's less caching for darwin, only happens on master and release branches or something | 00:03:39 |
| alexfmpe | historically I've seen my m1 get less caching of haskell-updates than my linux | 00:04:03 |
| ijouw | I am running nixos | 00:04:32 |
| alexfmpe | same | 00:04:50 |
| alexfmpe | try the above rev | 00:04:54 |
| alexfmpe | and the same --dry-run | 00:05:03 |
| ijouw | Oh, i was stil using ghcHEAD... | 00:07:09 |
| ijouw | git pull is taking a while | 00:17:57 |
| ijouw | Will sleep first. Thank you for the help and good night. | 00:37:40 |
| ijouw | It worked, thanks. | 14:52:34 |
| ijouw | Having it integrate with developPackage seems complicated. Will try shell env only. | 15:30:26 |
|  amadaluzia -> 4d2.org changed their display name from amadaluzia to amadaluzia[uorg]. | 18:48:52 |
|  amadaluzia joined the room. | 19:24:31 |
| amadaluzia -> 4d2.org changed their display name from amadaluzia[uorg] to amadaluzia -> 4d2.org. | 21:22:30 |
| 15 Mar 2026 |
|  eveeifyeve joined the room. | 13:40:03 |
| eveeifyeve | Does anyone know what is blocking this pr: https://github.com/NixOS/cabal2nix/pull/667? Because I would like to get a move along so I can close the opentracing tracking issue. | 13:41:02 |
| eveeifyeve | * sterni: what is blocking this pr: https://github.com/NixOS/cabal2nix/pull/667? Because I would like to get a move along so I can close the opentracing tracking issue. | 13:41:18 |
 sterni (he/him) | I think wolfgang doesn't have the time for it at the moment, but I'm not sure. | 13:42:04 |
