diff --git a/core/build.gradle.kts b/core/build.gradle.kts
index 4a5cd6fae..03c867f95 100644
--- a/core/build.gradle.kts
+++ b/core/build.gradle.kts
@@ -50,7 +50,7 @@ dependencies {
   testFixturesApi("io.ktor:ktor-serialization-kotlinx-json:$ktorVersion")
   testFixturesApi("io.ktor:ktor-server-content-negotiation:$ktorVersion")
 
-  testFixturesApi("org.jetbrains.kotlinx:kotlinx-serialization-json:1.3.3")
+  testFixturesApi("org.jetbrains.kotlinx:kotlinx-serialization-json:1.4.0")
 }
 
 testing {
diff --git a/json-schema/build.gradle.kts b/json-schema/build.gradle.kts
index 4fd1fee5c..099b292bb 100644
--- a/json-schema/build.gradle.kts
+++ b/json-schema/build.gradle.kts
@@ -18,7 +18,7 @@ sourdoughLibrary {
 
 dependencies {
   implementation("org.jetbrains.kotlin:kotlin-reflect:1.7.10")
-  implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.3.3")
+  implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.4.0")
 
   testImplementation(testFixtures(projects.kompendiumCore))
 }
diff --git a/oas/build.gradle.kts b/oas/build.gradle.kts
index d8d5bbcfe..d5fa3a46c 100644
--- a/oas/build.gradle.kts
+++ b/oas/build.gradle.kts
@@ -18,7 +18,7 @@ sourdoughLibrary {
 
 dependencies {
   api(projects.kompendiumJsonSchema)
-  implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.3.3")
+  implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.4.0")
 
   testImplementation(testFixtures(projects.kompendiumCore))
 }
diff --git a/playground/build.gradle.kts b/playground/build.gradle.kts
index cd652766b..be056fd48 100644
--- a/playground/build.gradle.kts
+++ b/playground/build.gradle.kts
@@ -37,7 +37,7 @@ dependencies {
   implementation("org.slf4j:slf4j-simple:1.7.36")
 
 
-  implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.3.3")
+  implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.4.0")
   implementation("org.jetbrains.kotlinx:kotlinx-datetime:0.4.0")
 
   implementation("joda-time:joda-time:2.10.14")