diff --git a/data/eval-machines.nix b/data/eval-machines.nix
index 4e32e6f..e41c793 100644
--- a/data/eval-machines.nix
+++ b/data/eval-machines.nix
@@ -3,10 +3,9 @@
 
 let
   network = import networkExpr;
-  pkgs    = network.network.pkgs;
-  lib     = pkgs.lib;
+  netPkgs = network.network.pkgs;
+  lib     = netPkgs.lib;
 in
-  with pkgs;
   with lib;
 
 rec {
@@ -18,10 +17,30 @@ rec {
         # expression, attaching _file attributes so the NixOS module
         # system can give sensible error messages.
         modules = [ { imports = [ network.${machineName} ]; } { inherit (network) _file; } ];
+
+        customPath = lib.attrByPath [ "deployment" "nixPath" ] [] (network.${machineName} { config = {}; pkgs = {}; });
+
+        # add path of network.pkgs if customPath is empty
+        netPath = if customPath == [] then [ { prefix = "nixpkgs"; path = netPkgs.path; } ] else [];
+
+        __nixPath = customPath ++ netPath ++ builtins.nixPath;
+
+        # must stay before __nixPath so we resolve <nixpkgs> correctly
+        importTarget = lib.attrByPath [ "deployment" "importPath" ] <nixpkgs/nixos/lib/eval-config.nix> (network.${machineName} { config = {}; pkgs = {}; });
+
+        importFn =
+          let
+            overrides = {
+              inherit __nixPath;
+              import = fn: scopedImport overrides fn;
+              scopedImport = attrs: fn: scopedImport (overrides // attrs) fn;
+              builtins = builtins // overrides;
+            };
+          in
+            scopedImport overrides;
       in
       { name = machineName;
-        value = import "${toString pkgs.path}/nixos/lib/eval-config.nix" {
-          inherit pkgs;
+        value = importFn importTarget {
           modules =
             modules ++
             [ { key = "deploy-stuff";
@@ -57,7 +76,7 @@ rec {
       flip mapAttrs nodes (n: v': let v = scrubOptionValue v'; in
         { inherit (v.config.deployment) targetHost secrets healthChecks buildOnly;
           name = n;
-          nixosRelease = v.config.system.nixos.release or (removeSuffix v.config.system.nixos.version.suffix v.config.system.nixos.version);
+          #nixosRelease = v.config.system.nixos.release or (removeSuffix v.config.system.nixos.version.suffix v.config.system.nixos.version);
         }
       );
 
@@ -68,7 +87,7 @@ rec {
   # Phase 2: build complete machine configurations.
   machines = { names, buildTargets ? null }:
     let nodes' = filterAttrs (n: v: elem n names) nodes; in
-    pkgs.runCommand "morph"
+    netPkgs.runCommand "morph"
       { preferLocalBuild = true; }
       (if buildTargets == null
       then ''
diff --git a/data/options.nix b/data/options.nix
index 4488c17..af87847 100644
--- a/data/options.nix
+++ b/data/options.nix
@@ -161,6 +161,25 @@ in
       type = str;
     };
 
+    nixPath = mkOption {
+      type = attrsOf unspecified;
+      default = [];
+      example = [ { prefix = "nixpkgs"; path = "/home/test/git"; } ];
+      dsecription = ''
+        Per machine NIX_PATH override(s)
+      '';
+
+    };
+
+    importPath = mkOption {
+      type = str;
+      dsecription = ''
+        Per machine import path of config evaluator (operating system entry point)
+
+        By default this is <nixpkgs/nixos/lib/eval-config.nix>
+      '';
+    };
+
     buildOnly = mkOption {
       type = bool;
       default = false;
diff --git a/examples/pinning.nix b/examples/pinning.nix
new file mode 100644
index 0000000..3dab9ad
--- /dev/null
+++ b/examples/pinning.nix
@@ -0,0 +1,74 @@
+let
+  # Pin the deployment package-set to a specific version of nixpkgs
+  oldPkgs = import (builtins.fetchTarball {
+    url = "https://github.com/NixOS/nixpkgs-channels/archive/98c1150f2cc62b94b693dce63adc1fbcbfe616f1.tar.gz";
+    sha256 = "1mdwn0qrjc8jli8cbi4cfkar6xq15l232r371p4b48v2d4bah3wp";
+  }) {};
+
+  #sysPkgs = import <nixpkgs> {};
+
+  newPkgs = import (builtins.fetchTarball {
+    url = "https://github.com/NixOS/nixpkgs-channels/archive/180aa21259b666c6b7850aee00c5871c89c0d939.tar.gz";
+    sha256 = "0gxd10djy6khbjb012s9fl3lpjzqaknfv2g4dpfjxwwj9cbkj04h";
+  }) {};
+
+  vpsfPkgs = builtins.fetchTarball {
+    url = "https://github.com/vpsfreecz/nixpkgs/archive/5dd15a4181fb260d1c006c4d00e4cc978cd89989.tar.gz";
+    sha256 = "0yg9059n08469mndvpq1f5x3lcnj9zrynkckwh9pii1ihimj6xyl";
+  };
+
+  vpsadminos = builtins.fetchTarball {
+    url = "https://github.com/vpsfreecz/vpsadminos/archive/c00b238f4d290c8eded24ca3d0ae97c320bded91.tar.gz";
+    sha256 = "10m9sc49gz5j71xwm65pdw4wz683w37csi5zjfrs1jxdgy70j0pd";
+  };
+
+in
+{
+  network =  {
+    pkgs = newPkgs;
+    description = "simple hosts";
+  };
+
+  # uses network.pkgs
+  "default_pkgs" = { config, pkgs, ... }: {
+    boot.isContainer = true;
+  };
+
+  # uses vpsfPkgs and vpsadminos
+  "vpsadminos" = { config, pkgs, ... }: {
+    boot.zfs.pools = {
+      tank = {
+      };
+    };
+
+    deployment = {
+      nixPath = [
+        { prefix = "nixpkgs"; path = vpsfPkgs; }
+        { prefix = "vpsadminos"; path = vpsadminos; }
+      ];
+      importPath = "${vpsadminos}/os/default.nix";
+    };
+  };
+
+  "custom" = { config, pkgs, ... }: {
+    boot.isContainer = true;
+
+    deployment = {
+      nixPath = [
+        { prefix = "nixpkgs"; path = vpsfPkgs; }
+      ];
+    };
+  };
+
+  /*
+  "old" = { config, pkgs, ... }: {
+    boot.isContainer = true;
+
+    deployment = {
+      nixPath = [
+        { prefix = "nixpkgs"; path = oldPkgs.path; }
+      ];
+    };
+  };
+  */
+}