diff --git a/src/float_vgrid.f90 b/src/float_vgrid.f90
index 793d151..7440e8d 100644
--- a/src/float_vgrid.f90
+++ b/src/float_vgrid.f90
@@ -1,8 +1,8 @@
 program float_vgrid
   ! Zeta is double precision. Convert to  single and rewrite. This stops small floating point errors.
   use M_CLI2
-  use vgrid
-  use utils
+  use vgrid_m
+  use utils_m
   implicit none
 
   type(vgrid_t) :: vgrid
diff --git a/src/gen_topo.f90 b/src/gen_topo.f90
index 267e6f7..7a6637f 100644
--- a/src/gen_topo.f90
+++ b/src/gen_topo.f90
@@ -13,7 +13,7 @@ module gen_topo_m
   !
   use iso_fortran_env
   use netcdf
-  use utils
+  use utils_m
   implicit none
 
   private
diff --git a/src/topography.f90 b/src/topography.f90
index 24a9b6f..6e082ab 100644
--- a/src/topography.f90
+++ b/src/topography.f90
@@ -1,8 +1,8 @@
-module topography
+module topography_m
   use iso_fortran_env
   use netcdf
-  use utils
-  use vgrid
+  use utils_m
+  use vgrid_m
   implicit none
 
   type topography_t
@@ -761,4 +761,4 @@ subroutine topography_mask(this, filename)
 
   end subroutine topography_mask
 
-end module topography
+end module topography_m
diff --git a/src/topogtools.f90 b/src/topogtools.f90
index c7b10bd..b864d88 100644
--- a/src/topogtools.f90
+++ b/src/topogtools.f90
@@ -2,7 +2,7 @@ program topogtools
   use, intrinsic :: iso_fortran_env
   use M_CLI2
   use gen_topo_m
-  use topography
+  use topography_m
   implicit none
 
   character(len=5), PARAMETER :: VERSION = "1.0.0"
diff --git a/src/utils.f90 b/src/utils.f90
index c2e936a..c097690 100644
--- a/src/utils.f90
+++ b/src/utils.f90
@@ -1,4 +1,4 @@
-module utils
+module utils_m
   use iso_fortran_env
   use netcdf
   implicit none
@@ -119,4 +119,4 @@ function get_mycommand() result(command)
 
   end function get_mycommand
 
-end module utils
+end module utils_m
diff --git a/src/vgrid.f90 b/src/vgrid.f90
index 9ade85e..43a5261 100644
--- a/src/vgrid.f90
+++ b/src/vgrid.f90
@@ -1,7 +1,7 @@
-module vgrid
+module vgrid_m
   use iso_fortran_env
   use netcdf
-  use utils
+  use utils_m
   implicit none
 
   private
@@ -207,4 +207,4 @@ subroutine vgrid_float(this)
   end subroutine vgrid_float
 
 
-end module vgrid
+end module vgrid_m