diff --git a/ueforth/esp32/config.h b/ueforth/esp32/config.h
index 4ea139b..4392872 100644
--- a/ueforth/esp32/config.h
+++ b/ueforth/esp32/config.h
@@ -12,6 +12,6 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#define HEAP_SIZE (100 * 1024)
+#define HEAP_SIZE (128 * 1024)
 #define STACK_CELLS 512
 #define INTERRUPT_STACK_CELLS 64