diff --git a/math/labplot/files/patch-src_backend_nsl_nsl__peak.h b/math/labplot/files/patch-src_backend_nsl_nsl__peak.h
new file mode 100644
index 000000000000..92db8d07230c
--- /dev/null
+++ b/math/labplot/files/patch-src_backend_nsl_nsl__peak.h
@@ -0,0 +1,11 @@
+--- src/backend/nsl/nsl_peak.h.orig	2025-08-14 23:00:36 UTC
++++ src/backend/nsl/nsl_peak.h
+@@ -13,7 +13,7 @@ template<typename T>
+ #include <cmath>
+ 
+ template<typename T>
+-size_t* nsl_peak_detect(T* data, size_t n, size_t& np, T height = -INFINITY, size_t distance = 0);
++std::size_t* nsl_peak_detect(T* data, std::size_t n, std::size_t& np, T height = -INFINITY, std::size_t distance = 0);
+ 
+ /* TODO: more advanced peak detection (CWT, etc.)*/
+