Add Tensorflow managed through Poetry environment

flutter.nix

@@ -3,7 +3,7 @@
 with pkgs;
 
 mkShell {
-  buildInputs = [ dart flutter androidenv.androidPkgs_9_0.androidsdk jdk ];
+  buildInputs = [ flutter hover androidenv.androidPkgs_9_0.androidsdk jdk ];
 
   ANDROID_HOME = "${androidenv.androidPkgs_9_0.androidsdk}/libexec/android-sdk";
   ANDROID_AVD_HOME = (toString ./.) + "/.android/avd";

mysql.nix

@@ -21,7 +21,9 @@ in mkShell {
     mysqld --datadir="${data_dir}" --socket="${socket}" --skip-networking --skip-mysqlx &
     sleep 1
 
+    if [ ! -d ${data_dir} ]; then
       mysql --socket="${socket}" -u root < ${sql_file}
+    fi
 
     alias mysql='mysql --socket="${socket}" -u root'
     alias nuke='rm -rf ${data_dir}'

postgresql.nix

@@ -22,7 +22,10 @@ in mkShell {
       pg_ctl start -o "--unix_socket_directories=${data_dir} --listen_addresses='''"
     fi
 
+    if [ ! -d ${data_dir} ]; then
       psql -d postgres -f ${sql_file}
+    fi
+
     alias psql='psql -d postgres'
     alias nuke='rm -rf ${data_dir}'
   '';

tensorflow-poetry.nix

@@ -0,0 +1,11 @@
+{ pkgs ? import <nixpkgs> { } }:
+
+with pkgs;
+
+mkShell {
+  buildInputs = [ python38 poetry ];
+  shellHook = ''
+    export LD_LIBRARY_PATH=${pkgs.stdenv.cc.cc.lib}/lib:$LD_LIBRARY_PATH
+    unset SOURCE_DATE_EPOCH
+  '';
+}