diff --git a/src/main/java/io/papermc/bibliothek/controller/v2/DownloadController.java b/src/main/java/io/papermc/bibliothek/controller/v2/DownloadController.java
index 4e46f7b..e752370 100644
--- a/src/main/java/io/papermc/bibliothek/controller/v2/DownloadController.java
+++ b/src/main/java/io/papermc/bibliothek/controller/v2/DownloadController.java
@@ -47,6 +47,7 @@
 import java.nio.file.Path;
 import java.time.Duration;
 import java.util.Map;
+import jakarta.validation.constraints.Positive;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.core.io.FileSystemResource;
 import org.springframework.http.CacheControl;
@@ -121,7 +122,7 @@ public ResponseEntity<?> download(
     final String versionName,
     @Parameter(description = "A build of the version.")
     @PathVariable("build")
-    @Pattern(regexp = "\\d+") //
+    @Positive //
     final int buildNumber,
     @Parameter(description = "A download of the build.")
     @PathVariable("download")
diff --git a/src/main/java/io/papermc/bibliothek/controller/v2/VersionBuildController.java b/src/main/java/io/papermc/bibliothek/controller/v2/VersionBuildController.java
index b4b4d47..b9fbfb8 100644
--- a/src/main/java/io/papermc/bibliothek/controller/v2/VersionBuildController.java
+++ b/src/main/java/io/papermc/bibliothek/controller/v2/VersionBuildController.java
@@ -43,6 +43,7 @@
 import java.time.Instant;
 import java.util.List;
 import java.util.Map;
+import jakarta.validation.constraints.Positive;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.CacheControl;
 import org.springframework.http.MediaType;
@@ -91,7 +92,7 @@ public ResponseEntity<?> build(
     final String versionName,
     @Parameter(description = "A build of the version.")
     @PathVariable("build")
-    @Pattern(regexp = "\\d+") //
+    @Positive //
     final int buildNumber
   ) {
     final Project project = this.projects.findByName(projectName).orElseThrow(ProjectNotFound::new);