diff --git a/pkgs/build-support/writers/test.nix b/pkgs/build-support/writers/test.nix
index e39681865ab2..996aaa01e9af 100644
--- a/pkgs/build-support/writers/test.nix
+++ b/pkgs/build-support/writers/test.nix
@@ -477,7 +477,11 @@ recurseIntoAttrs {
 
     yaml = expectDataEqual {
       file = writeYAML "data.yaml" { hello = "world"; };
-      expected = "hello: world\n";
+      expected = ''
+        %YAML 1.1
+        ---
+        hello: world
+      '';
     };
   };
 
diff --git a/pkgs/pkgs-lib/formats.nix b/pkgs/pkgs-lib/formats.nix
index e5f941af3770..a38b92f9444f 100644
--- a/pkgs/pkgs-lib/formats.nix
+++ b/pkgs/pkgs-lib/formats.nix
@@ -167,16 +167,16 @@ optionalAttrs allowAliases aliases
       generate =
         name: value:
         pkgs.callPackage (
-          { runCommand, remarshal_0_17 }:
+          { runCommand, remarshal }:
           runCommand name
             {
-              nativeBuildInputs = [ remarshal_0_17 ];
+              nativeBuildInputs = [ remarshal ];
               inherit value;
               preferLocalBuild = true;
               __structuredAttrs = true;
             }
             ''
-              json2yaml ${
+              remarshal --from json --to yaml-1.1 ${
                 # attributes with null values are omitted from the JSON with structured attrs
                 # yaml_1_1Null test keeps this in check
                 if value == null then ''<(echo "null")'' else ''--unwrap value "$NIX_ATTRS_JSON_FILE"''
diff --git a/pkgs/pkgs-lib/tests/formats.nix b/pkgs/pkgs-lib/tests/formats.nix
index b03b44c99150..56ce50ed6953 100644
--- a/pkgs/pkgs-lib/tests/formats.nix
+++ b/pkgs/pkgs-lib/tests/formats.nix
@@ -168,6 +168,8 @@ runBuildTests {
       time = "22:30:00";
     };
     expected = ''
+      %YAML 1.1
+      ---
       attrs:
         foo: null
       'false': false
@@ -188,8 +190,9 @@ runBuildTests {
     format = formats.yaml_1_1 { };
     input = null;
     expected = ''
-      null
-      ...
+      %YAML 1.1
+      ---
+        null
     '';
   };
 
diff --git a/pkgs/top-level/release-python.nix b/pkgs/top-level/release-python.nix
index 47b2133368b3..51407db2654f 100644
--- a/pkgs/top-level/release-python.nix
+++ b/pkgs/top-level/release-python.nix
@@ -54,7 +54,7 @@ let
       meta.description = "Release-critical packages from the python package sets";
       constituents = [
         jobs.nixos-render-docs.x86_64-linux # Used in nixos manual
-        jobs.remarshal_0_17.x86_64-linux # Used in pkgs.formats.yaml_1_1
+        jobs.remarshal.x86_64-linux # Used in pkgs.formats.yaml_1_1
         jobs.python313Packages.afdko.x86_64-linux # Used in noto-fonts-color-emoji
         jobs.python313Packages.buildcatrust.x86_64-linux # Used in pkgs.cacert
         jobs.python313Packages.colorama.x86_64-linux # Used in nixos test-driver