Add crate-specific overrides

build.nix

@@ -68,6 +68,8 @@
 , fetchurl
 , lndir
 , userAttrs
+, crateSpecificOverrides
+, pkgs
 }:
 
 let
@@ -130,14 +132,16 @@ let
       jq
       rsync
     ] ++ nativeBuildInputs
-      ++ lib.optionals (mode == "clippy") [clippy];
+      ++ lib.optionals (mode == "clippy") [clippy]
+      ++ neededCrateSpecificOverrides.nativeBuildInputs;
 
     buildInputs = lib.optionals stdenv.isDarwin [
       darwin.Security
       darwin.apple_sdk.frameworks.CoreServices
       darwin.cf-private
       darwin.libiconv
-    ] ++ buildInputs;
+    ] ++ buildInputs
+      ++ neededCrateSpecificOverrides.buildInputs;
 
     inherit builtDependencies;
 
@@ -374,6 +378,26 @@ let
     };
   };
 
+  neededCrateSpecificOverrides =
+    let
+      overridesList = builtins.map
+        ( crateInfo:
+          if builtins.hasAttr crateInfo.name crateSpecificOverrides then
+            crateSpecificOverrides.${crateInfo.name} { inherit crateInfo; }
+          else {}
+        )
+        cratesIoDependencies;
+    in builtins.foldl'
+      (acc: elem:
+        {
+          buildInputs =       acc.buildInputs       ++ elem.buildInputs or [];
+          nativeBuildInputs = acc.nativeBuildInputs ++ elem.nativeBuildInputs or [];
+        }
+      )
+      { buildInputs = []; nativeBuildInputs = []; }
+      overridesList;
+
+
   # Crates.io dependencies required to compile user's crate.
   #
   # As an output, for each dependency, this derivation produces a subdirectory

config.nix

@@ -1,4 +1,4 @@
-{ lib, libb, builtinz, arg }:
+{ lib, libb, builtinz, arg, pkgs }:
 let
   allowFun = attrs0: attrName: default:
     if builtins.hasAttr attrName attrs0 then
@@ -311,6 +311,8 @@ let
     # Example:
     #   [ { name = "wabt", version = "2.0.6", sha256 = "..." } ]
     cratesIoDependencies = libb.mkVersions buildPlanConfig.cargolock;
+
+    crateSpecificOverrides = import ./crate_specific.nix { inherit pkgs; };
   };
 
   # config used when planning the builds

crate_specific.nix

@@ -0,0 +1,8 @@
+{ pkgs }:
+
+{
+    openssl-sys = { ... }: {
+        nativeBuildInputs = with pkgs; [ pkg-config ];
+        buildInputs = with pkgs; [ openssl ];
+    };
+}

default.nix

@@ -13,6 +13,7 @@
 , writeText
 , zstd
 , clippy
+, pkgs
 }@defaultBuildAttrs:
 
 let
@@ -22,7 +23,7 @@ let
     { inherit lib writeText remarshal runCommandLocal formats; };
 
   mkConfig = arg:
-    import ./config.nix { inherit lib arg libb builtinz; };
+    import ./config.nix { inherit lib arg libb builtinz pkgs; };
 
   buildPackage = arg:
     let