Setting a developer mode and its implication

NOISE

@@ -108,3 +108,19 @@ ABSTRACT
   Do not use to ensure reproducibility.
 
 /* vim: set ts=2 sw=2 tw=72 fo=watqc expandtab spell autoindent: */
+
+1.8 Nix compilation environment
+
+  When using local repo as src code, (e.g. developer mode on) a make
+  clean at the preBuild stage is required.
+
+  Nix sets the current date to the files copied from repos.
+  Makefile checks the files modification date in order to call or not
+  the compilation instructions.
+  If any object/binary file exists out of Nix, at the time we build 
+  within Nix, they will be copied with the current data and consequently 
+  not updated during the Nix compilation process.
+
+  See saiph devMode option and its implications at   
+  bscpkgs/garlic/saiph/default.nix
+  

garlic/exp/saiph/numcomm.nix

@@ -12,6 +12,7 @@ with stdenv.lib;
 let
   # Set variable configuration for the experiment
   varConfig = {
+    devMode = [ true ];
     numComm = [ 1 ];
   };
 
@@ -148,7 +149,7 @@ let
       });
     in
     customPkgs.bsc.garlic.saiph.override {
-      inherit numComm mpi gitBranch;
+      inherit devMode numComm mpi gitBranch;
     };
 
   stages = with common; []

garlic/saiph/default.nix

@@ -6,6 +6,7 @@
 , cc 
 , vtk
 , boost
+, devMode ? false
 , gitBranch ? "master"
 , numComm ? null
 , vectFlags ? null
@@ -15,13 +16,13 @@
 stdenv.mkDerivation rec {
   name = "saiph";
 
-  src = builtins.fetchGit {
-    url = "ssh://git@bscpm02.bsc.es/DSLs/saiph.git";
-    ref = "${gitBranch}";
-  };
+  src = (if (devMode == true) then ~/repos/saiph
+         else
+	 builtins.fetchGit {
+           url = "ssh://git@bscpm02.bsc.es/DSLs/saiph.git";
+           ref = "${gitBranch}";
+         });
 
-  #src = /tmp/saiph;
-  
   programPath = "/bin/ExHeat3D";
 
   enableParallelBuilding = true;
@@ -42,11 +43,12 @@ stdenv.mkDerivation rec {
   hardeningDisable = [ "bindnow" ];
   
   preBuild = ''
-    cd saiphv2/cpp/src
-
+    cd saiphv2/cpp/src 
     export VTK_VERSION=8.2
     export VTK_HOME=${vtk}
-  '';
+  ''
+  + (if (devMode == true) then "make clean" else "")
+  ;
 
   makeFlags = [
     "-f" "Makefile.${cc.cc.CC}"