diff --git a/.github/workflows/ci-nix.yaml b/.github/workflows/ci-nix.yaml
index 836b739f517..83e4d777098 100644
--- a/.github/workflows/ci-nix.yaml
+++ b/.github/workflows/ci-nix.yaml
@@ -45,16 +45,8 @@ jobs:
         name: cardano-scaling
         authToken: '${{ secrets.CACHIX_CARDANO_SCALING_AUTH_TOKEN }}'
 
-    - name: ❓ Test (Pure)
-      if: ${{ matrix.package == 'hydra-plutus'
-           || matrix.package == 'plutus-cbor'
-           || matrix.package == 'plutus-merkle-tree' }}
-      run: |
-        nix build .#checks.x86_64-linux.${{ matrix.package }}
-
-    - name: ❓ Test (Impure)
-      if: ${{ matrix.package == 'hydra-cluster'
-           || matrix.package == 'hydra-node' }}
+    - name: ❓ Test
+      if: ${{ matrix.package != 'hydra-tui' }}
       run: |
         cd ${{ matrix.package }}
         nix build .#${{ matrix.package }}-tests
diff --git a/flake.nix b/flake.nix
index add6f85dec1..765e968f000 100644
--- a/flake.nix
+++ b/flake.nix
@@ -135,21 +135,6 @@
               ];
               treefmt = pkgs.treefmt;
             };
-            hydra-plutus = lu.tee-check {
-              name = "hydra-plutus";
-              src = self;
-              exe = "${packages.hydra-plutus-tests}/bin/tests";
-            };
-            plutus-cbor = lu.tee-check {
-              name = "plutus-cbor";
-              src = self;
-              exe = "${packages.plutus-cbor-tests}/bin/tests";
-            };
-            plutus-merkle-tree = lu.tee-check {
-              name = "plutus-merkle-tree";
-              src = self;
-              exe = "${packages.plutus-merkle-tree-tests}/bin/tests";
-            };
           } // lib.attrsets.mergeAttrsList (map (x: componentsToWerrors x hsPkgs.${x}) [
             "cardano-api-classy"
             "hydra-cardano-api"
@@ -176,8 +161,7 @@
           devShells = import ./nix/hydra/shell.nix {
             inherit inputs pkgs hsPkgs system compiler;
           };
-
-        };
+      };
     };
 
   nixConfig = {
diff --git a/hydra-plutus/hydra-plutus.cabal b/hydra-plutus/hydra-plutus.cabal
index 9241554dd6f..4ee6373498e 100644
--- a/hydra-plutus/hydra-plutus.cabal
+++ b/hydra-plutus/hydra-plutus.cabal
@@ -78,7 +78,7 @@ library
     , template-haskell
     , time
 
-executable tests
+test-suite tests
   import:             project-config
   ghc-options:        -threaded -rtsopts -with-rtsopts=-N
   hs-source-dirs:     test
diff --git a/nix/hydra/packages.nix b/nix/hydra/packages.nix
index a9605ab4229..e419d8a7947 100644
--- a/nix/hydra/packages.nix
+++ b/nix/hydra/packages.nix
@@ -121,10 +121,18 @@ rec {
 
   hydraw-static = musl64Pkgs.hydraw.components.exes.hydraw;
 
-  plutus-cbor-tests = nativePkgs.plutus-cbor.components.exes.tests;
-
-  plutus-merkle-tree-tests = nativePkgs.plutus-merkle-tree.components.exes.tests;
-  hydra-plutus-tests = nativePkgs.hydra-plutus.components.exes.tests;
+  plutus-cbor-tests = pkgs.mkShellNoCC {
+    name = "plutus-cbor-tests";
+    buildInputs = [ nativePkgs.plutus-cbor.components.tests.tests ];
+  };
+  plutus-merkle-tree-tests = pkgs.mkShellNoCC {
+    name = "plutus-merkle-tree-tests";
+    buildInputs = [ nativePkgs.plutus-merkle-tree.components.tests.tests ];
+  };
+  hydra-plutus-tests = pkgs.mkShellNoCC {
+    name = "hydra-plutus-tests";
+    buildInputs = [ nativePkgs.hydra-plutus.components.tests.tests ];
+  };
   hydra-node-tests = pkgs.mkShellNoCC {
     name = "hydra-node-tests";
     buildInputs = [
diff --git a/plutus-cbor/plutus-cbor.cabal b/plutus-cbor/plutus-cbor.cabal
index 564fff0f184..ac10dee4f4b 100644
--- a/plutus-cbor/plutus-cbor.cabal
+++ b/plutus-cbor/plutus-cbor.cabal
@@ -46,7 +46,7 @@ library
 
   exposed-modules: Plutus.Codec.CBOR.Encoding
 
-executable tests
+test-suite tests
   import:             project-config
   type:               exitcode-stdio-1.0
   hs-source-dirs:     test
diff --git a/plutus-merkle-tree/plutus-merkle-tree.cabal b/plutus-merkle-tree/plutus-merkle-tree.cabal
index 3f2c1311294..d14b7a209de 100644
--- a/plutus-merkle-tree/plutus-merkle-tree.cabal
+++ b/plutus-merkle-tree/plutus-merkle-tree.cabal
@@ -48,7 +48,7 @@ library
     , plutus-tx
     , text
 
-executable tests
+test-suite tests
   import:             project-config
   type:               exitcode-stdio-1.0
   hs-source-dirs:     test