diff --git a/sjsonnet/src/sjsonnet/Materializer.scala b/sjsonnet/src/sjsonnet/Materializer.scala
index 42a891bc..1fe40b6e 100644
--- a/sjsonnet/src/sjsonnet/Materializer.scala
+++ b/sjsonnet/src/sjsonnet/Materializer.scala
@@ -33,10 +33,7 @@ abstract class Materializer {
       case Val.False(_)  => "false"
       case Val.Null(_)   => "null"
       case Val.Num(_, _) =>
-        val d = v.asDouble
-        val l = d.toLong
-        if (l.toDouble == d) java.lang.Long.toString(l)
-        else RenderUtils.renderDouble(d)
+        RenderUtils.renderDouble(v.asDouble)
       case _ => apply0(v, new sjsonnet.Renderer()).toString
     }
   }
diff --git a/sjsonnet/src/sjsonnet/Renderer.scala b/sjsonnet/src/sjsonnet/Renderer.scala
index 5f925330..54069186 100644
--- a/sjsonnet/src/sjsonnet/Renderer.scala
+++ b/sjsonnet/src/sjsonnet/Renderer.scala
@@ -268,12 +268,18 @@ final case class MaterializeJsonRenderer(
 
 object RenderUtils {
 
+  // Pre-cached string representations of small integers (0-255)
+  private val intStrCache: Array[String] = Array.tabulate(256)(_.toString)
+
   /**
    * Custom rendering of Doubles used in rendering
    */
   def renderDouble(d: Double): String = {
-    if (d.toLong == d) d.toLong.toString
-    else if (d % 1 == 0) {
+    val l = d.toLong
+    if (l.toDouble == d) {
+      if (l >= 0 && l < 256) intStrCache(l.toInt)
+      else l.toString
+    } else if (d % 1 == 0) {
       BigDecimal(d).setScale(0, BigDecimal.RoundingMode.HALF_EVEN).toBigInt.toString()
     } else d.toString
   }