diff --git a/install/build.ninja b/install/build.ninja
index 39d1054..0593ad9 100644
--- a/install/build.ninja
+++ b/install/build.ninja
@@ -3,19 +3,19 @@
 # URLs
 ######
 
-URL_OPAM  ="http://raw.github.com/ocaml/opam/master/shell/opam_installer.sh"
-URL_IRPF90="http://github.com/scemama/irpf90/archive/v1.6.7.tar.gz"
-URL_EZFIO ="http://github.com/scemama/EZFIO/archive/v1.3.1.tar.gz"
+URL_OPAM  ="https://raw.github.com/ocaml/opam/master/shell/opam_installer.sh"
+URL_IRPF90="https://github.com/scemama/irpf90/archive/v1.6.7.tar.gz"
+URL_EZFIO ="https://github.com/scemama/EZFIO/archive/v1.3.1.tar.gz"
 
 URL_ZMQ   ="http://download.zeromq.org/zeromq-4.0.7.tar.gz"
 #URL_ZMQ   ="http://download.zeromq.org/zeromq-4.1.3.tar.gz"
-URL_F77ZMQ="http://github.com/scemama/f77_zmq/archive/v4.1.3.tar.gz"
+URL_F77ZMQ="https://github.com/scemama/f77_zmq/archive/v4.1.3.tar.gz"
 
 # Rules
 #######
 
 rule download
-  command = wget ${url} -O ${out} -o /dev/null
+  command = wget ${url} -O ${out}.tmp -o /dev/null && mv ${out}.tmp ${out}
   description = Downloading ${descr}
 
 rule install
diff --git a/install/scripts/install_ninja.sh b/install/scripts/install_ninja.sh
index 882437e..0525c22 100755
--- a/install/scripts/install_ninja.sh
+++ b/install/scripts/install_ninja.sh
@@ -20,7 +20,8 @@ function _install()
 
 if [[ ! -f "Downloads/${TARGET}.tar.gz" ]]
 then
-  wget ${URL} -O "Downloads/${TARGET}.tar.gz" 
+  wget ${URL} -O "Downloads/${TARGET}.tar.gz.tmp" 
+  mv "Downloads/${TARGET}.tar.gz"{.tmp,} 
 fi
 source scripts/build.sh