diff --git a/default.nix b/default.nix
index edb3e95c..481dd59a 100644
--- a/default.nix
+++ b/default.nix
@@ -217,6 +217,8 @@ let
     # note: pybind11 won't build on roly-chicago-24a in nix sandbox, runs out of pty devices
     #
     pkgs.python3Packages.pybind11
+    pkgs.python3Packages.json5
+    pkgs.python3Packages.jinja2
     pkgs.llvmPackages_18.llvm.dev
     pkgs.replxx
     pkgs.libwebsockets
diff --git a/xo-alloc2/docs/DArenaIterator-reference.rst b/xo-alloc2/docs/DArenaIterator-reference.rst
index 4ef4c196..c70bd642 100644
--- a/xo-alloc2/docs/DArenaIterator-reference.rst
+++ b/xo-alloc2/docs/DArenaIterator-reference.rst
@@ -3,7 +3,7 @@
 DArenaIterator
 ==============
 
-Iterator for allocs obtained from a :cpp:class:`DArena`.
+Iterator for allocs obtained from a :cpp:class:`xo::mm::DArena`.
 
 Context
 -------
diff --git a/xo-alloc2/docs/IAllocator_Xfer-reference.rst b/xo-alloc2/docs/IAllocator_Xfer-reference.rst
index 9ca90565..e57544b2 100644
--- a/xo-alloc2/docs/IAllocator_Xfer-reference.rst
+++ b/xo-alloc2/docs/IAllocator_Xfer-reference.rst
@@ -6,6 +6,9 @@ IAllocator_Xfer
 IAllocator_Xfer provides a type-erased interface to a specific native allocator
 implementation.
 
+It supports runtime polymorphism for the cpp:class:`xo::mm::AAllocator` facet.
+Application code iis unlikely to directly interact with this class
+
 Context
 -------
 
diff --git a/xo-alloc2/src/alloc2/ArenaConfig.cpp b/xo-alloc2/src/alloc2/ArenaConfig.cpp
index 942a7e91..7f4e4248 100644
--- a/xo-alloc2/src/alloc2/ArenaConfig.cpp
+++ b/xo-alloc2/src/alloc2/ArenaConfig.cpp
@@ -9,7 +9,7 @@ namespace xo {
         ArenaConfig
         ArenaConfig::simple(std::size_t z)
         {
-            return ArenaConfig { .size_ = z };
+            return ArenaConfig { .name_ = "anonymous", .size_ = z };
         }
     }
 }
diff --git a/xo-gc/include/xo/gc/AGCObject.hpp b/xo-gc/include/xo/gc/AGCObject.hpp
deleted file mode 100644
index 1e0a6d45..00000000
--- a/xo-gc/include/xo/gc/AGCObject.hpp
+++ /dev/null
@@ -1,53 +0,0 @@
-/** @file AGCObject.hpp
- *
- *  @author Roland Conybeare, Dec 2025
- **/
-
-#pragma once
-
-#include "Allocator.hpp"
-#include "xo/facet/facet_implementation.hpp"
-#include "xo/facet/typeseq.hpp"
-#include "xo/facet/obj.hpp"   // for obj<AAllocator> in shallow_copy
-#include <cstdint>
-#include <cstddef>
-
-namespace xo {
-    namespace mm {
-        using Copaque = const void *;
-        using Opaque = void *;
-
-        /** @class AObject
-         *  @brief Abstract facet for collector-eligible data
-         *
-         *  Data that supports AGCObject can have memory managed
-         *  by ACollector
-         **/
-        struct AGCObject {
-            using size_type = std::size_t;
-
-            /** RTTI: unique id# for actual runtime data representation **/
-            virtual int32_t _typeseq() const noexcept = 0;
-
-            virtual size_type shallow_size(Copaque d) const noexcept = 0;
-            virtual Opaque * shallow_copy(Copaque d,
-                                          obj<AAllocator> mm) const noexcept = 0;
-            virtual size_type forward_children(Opaque d) const noexcept = 0;
-        };
-
-        // implementation IGCObject_DRepr of AGCObject for state DRepr
-        // should provide a specialization:
-        //
-        //   template <>
-        //   struct xo::facet::FacetImplementation<AGCObjectx, DRepr> {
-        //       using ImplType = IGCObject_DRepr;
-        //   };
-        //
-        //   then IGCObject_ImplType<DRepr> --> IGCObject_DRepr
-        //
-        template <typename DRepr>
-        using IGCObject_ImplType = xo::facet::FacetImplType<AGCObject, DRepr>;
-    } /*namespace mm*/
-} /*namespace xo*/
-
-/* end AGCObject.hpp */
diff --git a/xo-gc/include/xo/gc/GCObject.hpp b/xo-gc/include/xo/gc/GCObject.hpp
index 524002a4..2674b2ae 100644
--- a/xo-gc/include/xo/gc/GCObject.hpp
+++ b/xo-gc/include/xo/gc/GCObject.hpp
@@ -5,7 +5,7 @@
 
 #pragma once
 
-#include "AGCObject.hpp"
+#include "detail/AGCObject.hpp"
 #include "detail/IGCObject_Any.hpp"
 #include "detail/IGCObject_Xfer.hpp"
 #include "detail/RGCObject.hpp"
diff --git a/xo-gc/include/xo/gc/detail/ACollector.hpp b/xo-gc/include/xo/gc/detail/ACollector.hpp
index d0d34bd7..24bd219e 100644
--- a/xo-gc/include/xo/gc/detail/ACollector.hpp
+++ b/xo-gc/include/xo/gc/detail/ACollector.hpp
@@ -27,7 +27,7 @@ namespace xo {
         /** @class ACollector
          *  @brief Abstract facet for the XO garbage collector
          *
-         *  Collector also supports the @ref AAllocator facet, see also
+         *  A collector implementation will also support the @ref AAllocator facet, see also
          **/
         struct ACollector {
             using size_type = std::size_t;
diff --git a/xo-object2/include/xo/object2/IGCObject_DFloat.hpp b/xo-object2/include/xo/object2/IGCObject_DFloat.hpp
index 1916f7e2..a6c5c17e 100644
--- a/xo-object2/include/xo/object2/IGCObject_DFloat.hpp
+++ b/xo-object2/include/xo/object2/IGCObject_DFloat.hpp
@@ -6,7 +6,7 @@
 #pragma once
 
 #include <xo/alloc2/alloc/AAllocator.hpp>
-#include <xo/gc/AGCObject.hpp>
+#include <xo/gc/detail/AGCObject.hpp>
 #include <xo/gc/detail/IGCObject_Xfer.hpp>
 #include "DFloat.hpp"
 
diff --git a/xo-object2/include/xo/object2/IGCObject_DInteger.hpp b/xo-object2/include/xo/object2/IGCObject_DInteger.hpp
index 69620b57..1f1f220c 100644
--- a/xo-object2/include/xo/object2/IGCObject_DInteger.hpp
+++ b/xo-object2/include/xo/object2/IGCObject_DInteger.hpp
@@ -6,7 +6,7 @@
 #pragma once
 
 #include "xo/alloc2/alloc/AAllocator.hpp"
-#include <xo/gc/AGCObject.hpp>
+#include <xo/gc/detail/AGCObject.hpp>
 #include <xo/gc/detail/IGCObject_Xfer.hpp>
 #include "DInteger.hpp"
 
diff --git a/xo-object2/include/xo/object2/IGCObject_DList.hpp b/xo-object2/include/xo/object2/IGCObject_DList.hpp
index 927feb74..8ba91a61 100644
--- a/xo-object2/include/xo/object2/IGCObject_DList.hpp
+++ b/xo-object2/include/xo/object2/IGCObject_DList.hpp
@@ -8,7 +8,7 @@
 #include <xo/alloc2/alloc/AAllocator.hpp>
 #include <xo/alloc2/alloc/RAllocator.hpp>
 #include <xo/gc/Collector.hpp>
-#include <xo/gc/AGCObject.hpp>
+#include <xo/gc/detail/AGCObject.hpp>
 #include <xo/gc/detail/IGCObject_Xfer.hpp>
 #include "DList.hpp"