diff --git a/nix/packages/by-name/ai_blocklist/package.nix b/nix/packages/by-name/ai_blocklist/package.nix
index d0b324e9..c967b129 100644
--- a/nix/packages/by-name/ai_blocklist/package.nix
+++ b/nix/packages/by-name/ai_blocklist/package.nix
@@ -3,14 +3,17 @@
   stdenvNoCC,
   lib,
 }:
-stdenvNoCC.mkDerivation (finalAttrs: {
+let
+  rev = "9bb188e2701138e03f73bacebd6b19b181ca0012";
+in
+stdenvNoCC.mkDerivation {
   pname = "ai_blocklist";
-  version = "unstable-" + lib.substring 0 8 finalAttrs.src.rev;
+  version = "unstable-" + lib.substring 0 8 rev;
 
   src = fetchFromGitHub {
     owner = "laylavish";
     repo = "uBlockOrigin-HUGE-AI-Blocklist";
-    rev = "9bb188e2701138e03f73bacebd6b19b181ca0012";
+    inherit rev;
     hash = "sha256-p3wfR28DH6V8BHn9DT10d09Yq3mdbBecWwlR1CdDYUA=";
   };
 
@@ -26,4 +29,4 @@ stdenvNoCC.mkDerivation (finalAttrs: {
     cat $out/share/hosts.txt |
       sed 's/^0.0.0.0 //' > $out/share/domains.txt
   '';
-})
+}
diff --git a/nix/packages/by-name/baguette_sharp/package.nix b/nix/packages/by-name/baguette-sharp/package.nix
similarity index 85%
rename from nix/packages/by-name/baguette_sharp/package.nix
rename to nix/packages/by-name/baguette-sharp/package.nix
index 1900da47..f7cb2967 100644
--- a/nix/packages/by-name/baguette_sharp/package.nix
+++ b/nix/packages/by-name/baguette-sharp/package.nix
@@ -2,9 +2,10 @@
   lib,
   fetchFromGitHub,
   fetchpatch,
+  ocaml,
   ocamlPackages,
 }:
-ocamlPackages.buildDunePackage (finalAttrs: {
+ocamlPackages.buildDunePackage rec {
   pname = "baguette_sharp";
   version = "2.3.0";
 
@@ -14,7 +15,7 @@ ocamlPackages.buildDunePackage (finalAttrs: {
   src = fetchFromGitHub {
     owner = "vanilla-extracts";
     repo = "ocaml-baguettesharp-interpreter";
-    rev = "v${finalAttrs.version}";
+    rev = "v${version}";
     hash = "sha256-GI60O6om71P3L+fGHGBCZ+U8vMlwPgYTWZCSCnEM0Wc=";
   };
 
@@ -22,9 +23,10 @@ ocamlPackages.buildDunePackage (finalAttrs: {
     fmt
     linenoise
   ];
+  doCheck = lib.versionAtLeast ocaml.version "4.13.1";
   patches = [
     (fetchpatch {
-      name = "dune-fix";
+      name = "fix dune";
       url = "https://github.com/vanilla-extracts/ocaml-baguettesharp-interpreter/commit/8809bc39a5e2cb02f757636f9939dc7818876779.patch";
       hash = "sha256-j0C2T3ZZ3K2Xvvl0qH5zl0znTkiUR8PO9FlqqPUX2aw=";
     })
@@ -34,6 +36,5 @@ ocamlPackages.buildDunePackage (finalAttrs: {
     homepage = "https://github.com/vanilla-extracts/ocaml-baguettesharp-interpreter";
     description = "OCaml Implementation of the (famous) Baguette# exotic language, used as TIPE for the 2022,2023 seasons concours";
     license = lib.licenses.gpl3Plus;
-    mainProgram = "baguette_sharp.repl";
   };
-})
+}
diff --git a/nix/packages/by-name/hategroup_blocklist/package.nix b/nix/packages/by-name/hategroup_blocklist/package.nix
index e6714157..3dc813bb 100644
--- a/nix/packages/by-name/hategroup_blocklist/package.nix
+++ b/nix/packages/by-name/hategroup_blocklist/package.nix
@@ -3,14 +3,17 @@
   stdenvNoCC,
   lib,
 }:
-stdenvNoCC.mkDerivation (finalAttrs: {
+let
+  rev = "cc19c050997d5f54014bb20c764b131e003dfb17";
+in
+stdenvNoCC.mkDerivation {
   pname = "hategroup_blocklist";
-  version = "unstable-" + lib.substring 0 8 finalAttrs.src.rev;
+  version = "unstable-" + lib.substring 0 8 rev;
 
   src = fetchFromGitHub {
     owner = "chigh";
     repo = "hategroup-dnsbl";
-    rev = "cc19c050997d5f54014bb20c764b131e003dfb17";
+    inherit rev;
     hash = "sha256-SZBrjIBUw687MdrbOV7WrP5IhAAtKvPL2GqdcICHNvQ=";
   };
 
@@ -25,4 +28,4 @@ stdenvNoCC.mkDerivation (finalAttrs: {
     cat $out/share/domains.txt |
       sed 's/^\([^#].*\)$/0.0.0.0 \1/' > $out/share/hosts.txt
   '';
-})
+}
diff --git a/nix/packages/by-name/hrt-time/package.nix b/nix/packages/by-name/hrt-time/package.nix
index cf76163b..29a50de3 100644
--- a/nix/packages/by-name/hrt-time/package.nix
+++ b/nix/packages/by-name/hrt-time/package.nix
@@ -3,14 +3,17 @@
   stdenvNoCC,
   lib,
 }:
-stdenvNoCC.mkDerivation (finalAttrs: {
+let
+  rev = "b344ab770e4c08d0bb13c38ea61979b282e24db7";
+in
+stdenvNoCC.mkDerivation {
   pname = "hrt-time";
-  version = "unstable-" + lib.substring 0 8 finalAttrs.src.rev;
+  version = "unstable-" + lib.substring 0 8 rev;
 
   src = fetchFromGitHub {
     owner = "ariannelafraise";
     repo = "hrt-time";
-    rev = "b344ab770e4c08d0bb13c38ea61979b282e24db7";
+    inherit rev;
     hash = "sha256-+AhLkcCETVnF6S+ov1oKxhs3M9F6ghyyERoLN3aMMxw=";
   };
 
@@ -28,4 +31,4 @@ stdenvNoCC.mkDerivation (finalAttrs: {
   ];
 
   meta.mainProgram = "hrt-time";
-})
+}
diff --git a/nix/packages/by-name/necrolib/package.nix b/nix/packages/by-name/necrolib/package.nix
index 50ea1abb..9b8ac1c2 100644
--- a/nix/packages/by-name/necrolib/package.nix
+++ b/nix/packages/by-name/necrolib/package.nix
@@ -1,10 +1,14 @@
 {
   fetchFromGitLab,
-  ocamlPackages,
+  ocaml-ng,
+  ocamlPackages ? ocaml-ng.ocamlPackages_5_1,
 }:
-ocamlPackages.buildDunePackage (finalAttrs: {
+let
+  version = "v0.16.2";
+in
+ocamlPackages.buildDunePackage {
   pname = "necrolib";
-  version = "0.16.2";
+  inherit version;
 
   minimalOCamlVersion = "5.1.1";
 
@@ -12,8 +16,8 @@ ocamlPackages.buildDunePackage (finalAttrs: {
     domain = "gitlab.inria.fr";
     owner = "skeletons";
     repo = "necro";
-    rev = "v${finalAttrs.version}";
-    hash = "sha256-u5evoyVW6RP7uwvdH7MK0cEbXt+GEAMw78MiOLlYTA0=";
+    rev = version;
+    hash = "sha256-KoSKJD5jy+GY5QKKMUTW5gc0V/5l/klHrJMdC8aPnj8=";
   };
 
   duneVersion = "3";
@@ -22,4 +26,4 @@ ocamlPackages.buildDunePackage (finalAttrs: {
     ocamlPackages.ocamlgraph
     ocamlPackages.dune-build-info
   ];
-})
+}
diff --git a/nix/packages/by-name/po210/package.nix b/nix/packages/by-name/po210/package.nix
index 3bd5a2b8..7679bc9b 100644
--- a/nix/packages/by-name/po210/package.nix
+++ b/nix/packages/by-name/po210/package.nix
@@ -1,17 +1,20 @@
 {
-  lib,
-  fetchFromGitea,
-  stdenv,
+lib,
+fetchFromGitea,
+stdenv,
 }:
-stdenv.mkDerivation (finalAttrs: {
+let
+  rev = "64fbd20e6a888cc974cefbf56275c99333d8f6e9";
+in
+stdenv.mkDerivation {
   pname = "po210";
-  version = "unstable-" + lib.substring 0 8 finalAttrs.src.rev;
+  version = "unstable-" + lib.substring 0 8 rev;
 
   src = fetchFromGitea {
     domain = "git.disroot.org";
     owner = "80486DX2-66";
     repo = "po210";
-    rev = "64fbd20e6a888cc974cefbf56275c99333d8f6e9";
+    inherit rev;
     hash = "sha256-ph55vv5jiR7OiC9qKwG6WFqI1cTwtAEHZnc2Wd6X134=";
   };
 
@@ -20,4 +23,4 @@ stdenv.mkDerivation (finalAttrs: {
   '';
 
   meta.mainProgram = "po210";
-})
+}
diff --git a/nix/packages/by-name/typst-bot/package.nix b/nix/packages/by-name/typst-bot/package.nix
index ffca5ea8..f7a50b00 100644
--- a/nix/packages/by-name/typst-bot/package.nix
+++ b/nix/packages/by-name/typst-bot/package.nix
@@ -3,20 +3,23 @@
   rustPlatform,
   fetchFromGitHub,
 }:
+let
+  rev = "c9d4b164ff5dc2567bb0de3876460e51da62ba94";
+in
 rustPlatform.buildRustPackage (finalAttrs: {
   pname = "typst-bot";
-  version = lib.substring 0 8 finalAttrs.src.rev;
+  version = lib.substring 0 8 rev;
 
   src = fetchFromGitHub {
     owner = "mattfbacon";
     repo = "typst-bot";
-    rev = "c9d4b164ff5dc2567bb0de3876460e51da62ba94";
+    inherit rev;
     hash = "sha256-tB+zrE5p7zOloOgoP2fmFsajd4IBf94ET1v/0W3aNcM=";
   };
 
   preBuild = ''
     # Don't use the upstream way of embedding the git rev
-    echo 'fn main() { println!("cargo:rustc-env=BUILD_SHA=${finalAttrs.src.rev}"); }' > crates/bot/build.rs
+    echo 'fn main() { println!("cargo:rustc-env=BUILD_SHA=${rev}"); }' > crates/bot/build.rs
 
     # Patch the command calling the worker by name.
     substituteInPlace crates/bot/src/worker.rs --replace-fail \