diff --git a/pkgs/by-name/ac/acl2/libipasirglucose4/default.nix b/pkgs/by-name/ac/acl2/libipasirglucose4/default.nix
index e52e45ee1a03..1028453b0ab0 100644
--- a/pkgs/by-name/ac/acl2/libipasirglucose4/default.nix
+++ b/pkgs/by-name/ac/acl2/libipasirglucose4/default.nix
@@ -6,18 +6,18 @@
   unzip,
 }:
 
-stdenv.mkDerivation rec {
+stdenv.mkDerivation (finalAttrs: {
   pname = "libipasirglucose4";
   # This library has no version number AFAICT (beyond generally being based on
   # Glucose 4.x), but it was submitted to the 2017 SAT competition so let's use
   # that as the version number, I guess.
   version = "2017";
 
-  libname = pname + stdenv.hostPlatform.extensions.sharedLibrary;
+  libname = finalAttrs.pname + stdenv.hostPlatform.extensions.sharedLibrary;
 
   src = fetchurl {
     url = "https://baldur.iti.kit.edu/sat-competition-2017/solvers/incremental/glucose-ipasir.zip";
-    sha256 = "0xchgady9vwdh8frmc8swz6va53igp2wj1y9sshd0g7549n87wdj";
+    hash = "sha256-svGDbCLlPNCg1skHycV9cRS1zecasZodgo3v5Jt6kHU=";
   };
   nativeBuildInputs = [ unzip ];
 
@@ -29,13 +29,13 @@ stdenv.mkDerivation rec {
   makeFlags = [ "CXX=${stdenv.cc.targetPrefix}c++" ];
 
   postBuild = ''
-    $CXX -shared -o ${libname} \
-        ${lib.optionalString (!stdenv.cc.isClang) "-Wl,-soname,${libname}"} \
+    $CXX -shared -o ${finalAttrs.libname} \
+        ${lib.optionalString (!stdenv.cc.isClang) "-Wl,-soname,${finalAttrs.libname}"} \
         ipasirglucoseglue.o libipasirglucose4.a
   '';
 
   installPhase = ''
-    install -D ${libname} $out/lib/${libname}
+    install -D ${finalAttrs.libname} $out/lib/${finalAttrs.libname}
   '';
 
   meta = {
@@ -44,4 +44,4 @@ stdenv.mkDerivation rec {
     platforms = lib.platforms.unix;
     maintainers = with lib.maintainers; [ kini ];
   };
-}
+})