diff --git a/CMakeLists.txt b/CMakeLists.txt
index 505dbcd8..bff25696 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -86,30 +86,31 @@ add_subdirectory(xo-randomgen)    # xoshiro256ss
 add_subdirectory(xo-reflectutil)  # header-only reflect support
 add_subdirectory(xo-arena)        # arena allocator (DArena)
 add_subdirectory(xo-facet)        # sep iface,data
-add_subdirectory(xo-printable2)   # experiment w/ facet object model
+add_subdirectory(xo-printable2)   # experiment w/ facet object model (fomo)
 add_subdirectory(xo-testutil)     # unit test aux functions
-add_subdirectory(xo-alloc2)       # experiment w/ facet object model
+add_subdirectory(xo-alloc2)       # arena api (fomo)
 add_subdirectory(xo-refcnt)
 add_subdirectory(xo-pyutil)
 add_subdirectory(xo-reflect)      # reflection library (pre-fomo)
 add_subdirectory(xo-pyreflect)
 add_subdirectory(xo-stringtable2) # experiment w/ facet object model
 add_subdirectory(xo-object2)      # experiment w/ facet object model
-add_subdirectory(xo-gc)           # experiment w/ facet object model
+add_subdirectory(xo-gc)           # incremental gc + facet object model
 add_subdirectory(xo-type)         # experiment w/ facet object model
 add_subdirectory(xo-procedure2)   # schematika procedure abstraction + runtime context (fomo)
 add_subdirectory(xo-numeric)      # schematika poly arithmetic w/ facet object model
+add_subdirectory(xo-tokenizer2)   # schematika tokenizer (w/ fomo)
+
 add_subdirectory(xo-allocutil)    # xo-alloc api
+add_subdirectory(xo-alloc)        # arena allocator + incremental gc
 add_subdirectory(xo-ratio)
 add_subdirectory(xo-unit)
 add_subdirectory(xo-pyunit)
 add_subdirectory(xo-callback)
-add_subdirectory(xo-alloc)
 #add_subdirectory(xo-reflect2)     # experiment w/ facet object model
 add_subdirectory(xo-object)
 add_subdirectory(xo-ordinaltree)
 #
-add_subdirectory(xo-tokenizer2)   # schematika tokenizer (fomo)
 add_subdirectory(xo-expression2)  # schematika expressions (fomo)
 add_subdirectory(xo-reader2)      # schematika expression parser (fomo)
 add_subdirectory(xo-interpreter2) # schematika interpreter (fomo)
diff --git a/ci.nix b/ci.nix
index 149c7bb5..300e3854 100644
--- a/ci.nix
+++ b/ci.nix
@@ -33,14 +33,14 @@ in
       xo-type
       xo-procedure2
       xo-numeric
+      xo-tokenizer2
       xo-allocutil
+      xo-alloc
       xo-ratio
       xo-unit
       xo-callback
-      xo-alloc
       xo-object
       xo-ordinaltree
-      xo-tokenizer2
       xo-expression
       xo-tokenizer
       xo-reader
diff --git a/shells.nix b/shells.nix
index 9b7bd162..fb9a4dd8 100644
--- a/shells.nix
+++ b/shells.nix
@@ -336,15 +336,16 @@ in
     type           = pkgs.xo-type;
     procedure2     = pkgs.xo-procedure2;
     numeric        = pkgs.xo-numeric;
+    tokenizer2     = pkgs.xo-tokenizer2;
+
     allocutil      = pkgs.xo-allocutil;
+    alloc          = pkgs.xo-alloc;
     ratio          = pkgs.xo-ratio;
     unit           = pkgs.xo-unit;
     pyunit         = pkgs.xo-pyunit;
     callback       = pkgs.xo-callback;
-    alloc          = pkgs.xo-alloc;
     object         = pkgs.xo-object;
     ordinaltree    = pkgs.xo-ordinaltree;
-    tokenizer2     = pkgs.xo-tokenizer2;
 
     webutil        = pkgs.xo-webutil;
     pywebutil      = pkgs.xo-pywebutil;
diff --git a/xo-cmake/etc/xo/subsystem-list b/xo-cmake/etc/xo/subsystem-list
index 48473e50..6568ccbc 100644
--- a/xo-cmake/etc/xo/subsystem-list
+++ b/xo-cmake/etc/xo/subsystem-list
@@ -19,6 +19,7 @@ xo-gc
 xo-type
 xo-procedure2
 xo-numeric
+xo-tokenizer2
 xo-allocutil
 xo-alloc
 xo-object
diff --git a/xo.nix b/xo.nix
index f5d83531..8ce8db92 100644
--- a/xo.nix
+++ b/xo.nix
@@ -46,15 +46,16 @@ let
     xo-type           = callPackage pkgs/xo-type.nix           { stdenv = jitStdenv; };
     xo-procedure2     = callPackage pkgs/xo-procedure2.nix     { stdenv = jitStdenv; };
     xo-numeric        = callPackage pkgs/xo-numeric.nix        { stdenv = jitStdenv; };
+    xo-tokenizer2     = callPackage pkgs/xo-tokenizer2.nix     { stdenv = jitStdenv;                   buildExamples = true; };
     xo-allocutil      = callPackage pkgs/xo-allocutil.nix      { stdenv = jitStdenv; };
+    xo-alloc          = callPackage pkgs/xo-alloc.nix          { stdenv = jitStdenv; buildDocs = true; };
     xo-ratio          = callPackage pkgs/xo-ratio.nix          { stdenv = jitStdenv; buildDocs = true; buildExamples = true; };
     xo-unit           = callPackage pkgs/xo-unit.nix           { stdenv = jitStdenv; buildDocs = true; buildExamples = true; };
     xo-pyunit         = callPackage pkgs/xo-pyunit.nix         { stdenv = jitStdenv; };
     xo-callback       = callPackage pkgs/xo-callback.nix       { stdenv = jitStdenv; };
-    xo-alloc          = callPackage pkgs/xo-alloc.nix          { stdenv = jitStdenv; buildDocs = true; };
     xo-object         = callPackage pkgs/xo-object.nix         { stdenv = jitStdenv; };
     xo-ordinaltree    = callPackage pkgs/xo-ordinaltree.nix    { stdenv = jitStdenv; };
-    xo-tokenizer2     = callPackage pkgs/xo-tokenizer2.nix     { stdenv = jitStdenv;                   buildExamples = true; };
+ = true; };
     xo-webutil        = callPackage pkgs/xo-webutil.nix        { stdenv = jitStdenv; };
     xo-pywebutil      = callPackage pkgs/xo-pywebutil.nix      {};
     xo-printjson      = callPackage pkgs/xo-printjson.nix      {};