diff --git a/build.nix b/build.nix
index 0aea21fc05..2bf29be8de 100644
--- a/build.nix
+++ b/build.nix
@@ -26,13 +26,7 @@ in rec {
 
   tools = pkgs.lib.optionalAttrs (ifdLevel >= 3) (
     pkgs.recurseIntoAttrs ({
-      cabal-latest = tool compiler-nix-name "cabal" {
-        inherit evalPackages;
-        cabalProjectLocal = ''
-          if impl(ghc <8.11)
-            constraints: os-string < 2.0
-        '';
-      };
+      cabal-latest = tool compiler-nix-name "cabal" { inherit evalPackages; };
     } // pkgs.lib.optionalAttrs (__compareVersions haskell.compiler.${compiler-nix-name}.version "9.8" < 0) {
       hlint-latest = tool compiler-nix-name "hlint" {
         inherit evalPackages;
diff --git a/test/cabal-doctests/cabal-doctests-test.cabal b/test/cabal-doctests/cabal-doctests-test.cabal
index f6c2617742..36eb9ee6df 100644
--- a/test/cabal-doctests/cabal-doctests-test.cabal
+++ b/test/cabal-doctests/cabal-doctests-test.cabal
@@ -16,7 +16,7 @@ library
   other-modules: Paths_cabal_doctests_test
   build-depends:
       base >=4.7 && <5,
-      aeson > 2
+      aeson
   default-language: Haskell2010
 
 test-suite doctests
diff --git a/test/cabal-simple-debug/cabal-simple.cabal b/test/cabal-simple-debug/cabal-simple.cabal
index ddcfac27b2..aef0f956db 100644
--- a/test/cabal-simple-debug/cabal-simple.cabal
+++ b/test/cabal-simple-debug/cabal-simple.cabal
@@ -21,7 +21,7 @@ library
   build-depends:       base
                      , extra
                      , safe
-                     , aeson > 2
+                     , aeson
   -- hs-source-dirs:
   default-language:    Haskell2010
 
diff --git a/test/cabal-simple-prof/cabal-simple.cabal b/test/cabal-simple-prof/cabal-simple.cabal
index ddcfac27b2..aef0f956db 100644
--- a/test/cabal-simple-prof/cabal-simple.cabal
+++ b/test/cabal-simple-prof/cabal-simple.cabal
@@ -21,7 +21,7 @@ library
   build-depends:       base
                      , extra
                      , safe
-                     , aeson > 2
+                     , aeson
   -- hs-source-dirs:
   default-language:    Haskell2010
 
diff --git a/test/cabal-source-repo-comments/cabal.project b/test/cabal-source-repo-comments/cabal.project
index 7d6813a19c..b2fc5fc7e8 100644
--- a/test/cabal-source-repo-comments/cabal.project
+++ b/test/cabal-source-repo-comments/cabal.project
@@ -2,7 +2,6 @@ packages:
   ./
 
 allow-newer: aeson:base, aeson:ghc-prim, aeson:template-haskell
-constraints: aeson >2
 
 source-repository-package
   -- Test
diff --git a/test/cabal-sublib/cabal-sublib.cabal b/test/cabal-sublib/cabal-sublib.cabal
index 973621b019..ef75a33b60 100644
--- a/test/cabal-sublib/cabal-sublib.cabal
+++ b/test/cabal-sublib/cabal-sublib.cabal
@@ -26,7 +26,7 @@ library
 library slib
   build-depends:       extra
                      , safe
-                     , aeson > 2
+                     , aeson
   default-language:    Haskell2010
 
 executable cabal-sublib
diff --git a/test/cabal.project.local b/test/cabal.project.local
index 174402f804..b79d2c0412 100644
--- a/test/cabal.project.local
+++ b/test/cabal.project.local
@@ -7,12 +7,6 @@ if impl(ghc>=9.8)
 if impl(ghc > 9.9)
   allow-newer: *:containers
 
-if impl(ghc <8.11)
-  constraints: os-string < 2.0
-
-if os(osx) && impl(ghc <8.11)
-  constraints: text -simdutf
-
 -- This prevents hsc2hs from causing old versions of packages from being added to plan.json
 allow-newer: hsc2hs:*
 
@@ -37,10 +31,10 @@ if !impl(ghc>=9.10) && !os(ghcjs)
   active-repositories: hackage.haskell.org
 
 if impl(ghc>=9.10) && !os(ghcjs)
-  active-repositories: hackage.haskell.org, head.hackage.ghc.haskell.org
+  active-repositories: hackage.haskell.org, head.hackage.ghc.haskell.org:override
 
 if !impl(ghc>=9.10) && os(ghcjs)
   active-repositories: hackage.haskell.org, ghcjs-overlay:override
 
 if impl(ghc>=9.10) && os(ghcjs)
-  active-repositories: hackage.haskell.org, head.hackage.ghc.haskell.org, ghcjs-overlay:override
+  active-repositories: hackage.haskell.org, head.hackage.ghc.haskell.org:override, ghcjs-overlay:override
diff --git a/test/sublib-docs/sublib-docs.cabal b/test/sublib-docs/sublib-docs.cabal
index 10bd1594bc..6ab6296258 100644
--- a/test/sublib-docs/sublib-docs.cabal
+++ b/test/sublib-docs/sublib-docs.cabal
@@ -29,7 +29,7 @@ library slib
   exposed-modules: Slib
   build-depends:       extra
                      , safe
-                     , aeson > 2
+                     , aeson
                      , base
   default-language:    Haskell2010
   hs-source-dirs:      slib
diff --git a/test/th-dlls/cabal.project b/test/th-dlls/cabal.project
index b860d6c3a6..f686c244f5 100644
--- a/test/th-dlls/cabal.project
+++ b/test/th-dlls/cabal.project
@@ -4,5 +4,3 @@ packages: .
 -- See https://github.com/haskell/network/issues/550
 constraints: network <3.1.3.0 || >3.1.3.0
 
-if os(osx) && impl(ghc<9.4)
-  constraints: text -simdutf