diff --git a/.github/workflows/pull-request.yml b/.github/workflows/pull-request.yml
index 7ceaf9fe..85149530 100644
--- a/.github/workflows/pull-request.yml
+++ b/.github/workflows/pull-request.yml
@@ -24,23 +24,3 @@ jobs:
           restore-keys: ${{ runner.os }}-m2
       - name: Build with Maven
         run: mvn --batch-mode --update-snapshots verify
-
-  # The same jar has to work with the oldest supported graphql-java, so build and test against it too
-  graphql-java-25:
-    runs-on: ubuntu-latest
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v7
-      - name: Setup java
-        uses: actions/setup-java@v6
-        with:
-          java-version: '11'
-          distribution: 'temurin'
-      - name: Cache Maven packages
-        uses: actions/cache@v6
-        with:
-          path: ~/.m2
-          key: ${{ runner.os }}-m2-${{ hashFiles('**/pom.xml') }}
-          restore-keys: ${{ runner.os }}-m2
-      - name: Build with Maven
-        run: mvn --batch-mode --update-snapshots verify -Dgraphql-java.version=25.1
diff --git a/src/main/kotlin/graphql/kickstart/tools/SdlDirectives.kt b/src/main/kotlin/graphql/kickstart/tools/SdlDirectives.kt
index 6f0f6d7f..7a469012 100644
--- a/src/main/kotlin/graphql/kickstart/tools/SdlDirectives.kt
+++ b/src/main/kotlin/graphql/kickstart/tools/SdlDirectives.kt
@@ -39,7 +39,7 @@ internal class SdlDirectives(
     }
 
     private fun isNonRepeatableByFirstDeclaration(directiveName: String): Boolean =
-        directiveDefinitions.find { it.name == directiveName }?.let { !it.isRepeatable } ?: BUILT_IN_DIRECTIVES.containsKey(directiveName)
+        directiveDefinitions.find { it.name == directiveName }?.let { !it.isRepeatable } ?: Directives.BUILT_IN_DIRECTIVES_MAP.containsKey(directiveName)
 
     private fun createDirectives() {
         schemaDirectives = directiveDefinitions.associateTo(linkedMapOf()) { it.name to createDirective(it) }
@@ -143,7 +143,7 @@ internal class SdlDirectives(
             }
         }
 
-    private fun findDirective(name: String): GraphQLDirective? = schemaDirectives[name] ?: BUILT_IN_DIRECTIVES[name]
+    private fun findDirective(name: String): GraphQLDirective? = schemaDirectives[name] ?: Directives.BUILT_IN_DIRECTIVES_MAP[name]
 
     // there's no directive definition to look the type up in, so it's guessed from the value
     private fun guessDirectiveArgumentType(directive: Directive, argumentName: String, value: Value<*>): GraphQLInputType {
@@ -239,14 +239,3 @@ internal class SdlDirectives(
         }
 }
 
-// Built from the individual constants rather than Directives.BUILT_IN_DIRECTIVES_MAP (added in graphql-java 26)
-// so that the library keeps working with graphql-java 25. TODO replace with Directives.BUILT_IN_DIRECTIVES_MAP once we deploy a major version
-private val BUILT_IN_DIRECTIVES = listOf(
-    Directives.IncludeDirective,
-    Directives.SkipDirective,
-    Directives.DeprecatedDirective,
-    Directives.SpecifiedByDirective,
-    Directives.OneOfDirective,
-    Directives.DeferDirective,
-    Directives.ExperimentalDisableErrorPropagationDirective
-).associateBy { it.name }
diff --git a/src/test/kotlin/graphql/kickstart/tools/TypeExtensionTest.kt b/src/test/kotlin/graphql/kickstart/tools/TypeExtensionTest.kt
index c6c6acb2..680835aa 100644
--- a/src/test/kotlin/graphql/kickstart/tools/TypeExtensionTest.kt
+++ b/src/test/kotlin/graphql/kickstart/tools/TypeExtensionTest.kt
@@ -71,8 +71,8 @@ class TypeExtensionTest {
         assertEquals(date.description, "A date")
         assertEquals(date.appliedDirectives.map { it.name }, listOf("format"))
 
-        // through GraphQLNamedSchemaElement, since graphql-java 25 and 26 disagree on which types have a nullable definition
-        assertEquals(listOf<GraphQLNamedSchemaElement>(fooBar, color, node, item, date).map { it.definition?.javaClass }, listOf(
+        val definitions = listOf(fooBar.definition, color.definition, node.definition, item.definition, date.definition)
+        assertEquals(definitions.map { it?.javaClass }, listOf(
             UnionTypeDefinition::class.java,
             EnumTypeDefinition::class.java,
             InterfaceTypeDefinition::class.java,