diff --git a/pyproject.toml b/pyproject.toml
index 9344d3e9..7147db73 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -75,12 +75,14 @@ dependencies = [
     "trio-typing>=0.10.0",
     "numba>=0.61.0",
     "pyvnc",
-    # TODO? mv to dev group?
-    "pdbp >=1.5.0, <2.0.0",
 ]
 # ------ dependencies ------
 
 
+# TODO: add an `--only daemon` group for running non-ui / pikerd
+# service tree in distributed mode B)
+# https://docs.astral.sh/uv/concepts/projects/dependencies/#optional-dependencies
+
 [dependency-groups]
 uis = [
     # https://docs.astral.sh/uv/concepts/projects/dependencies/#optional-dependencies
@@ -91,9 +93,9 @@ uis = [
     # for consideration,
     # - 'visidata'
 
-    # TODO: add an `--only daemon` group for running non-ui / pikerd
-    # service tree in distributed mode B)
-    # https://docs.astral.sh/uv/concepts/projects/dependencies/#optional-dependencies
+    "qdarkstyle >=3.0.2, <4.0.0",
+    "pyqt6 >=6.7.0, <7.0.0",
+    "pyqtgraph",
 ]
 
 # TODO: a toolset that makes debugging a `pikerd` service (tree) easy
@@ -104,23 +106,32 @@ uis = [
 #
 # console ehancements and eventually remote debugging extras/helpers.
 # use `uv --dev` to enable
-dev = [
-    "pytest",
-    "prompt-toolkit ==3.0.40",
-    "cython >=3.0.0, <4.0.0",
+repl = [
+  # debug
+  "pdbp >=1.5.0, <2.0.0",
     "greenback >=1.1.1, <2.0.0",
+  "xonsh",
+    "prompt-toolkit ==3.0.40",
     "pyperclip>=1.9.0",
-    # DE-specific
-    "i3ipc>=2.2.1",
 
-    # ?from git, see below.
-    "xonsh",
+]
+testing = [
+  "pytest",
+]
+de = [
+  # DE-specific
+  "i3ipc>=2.2.1",
+]
+dev = [
+  # https://docs.astral.sh/uv/concepts/projects/dependencies/#development-dependencies
+  "cython >=3.0.0, <4.0.0",
 
-    # TODO! use nested groups for these UI libs!
-    # https://docs.astral.sh/uv/concepts/projects/dependencies/#nesting-groups
-    "qdarkstyle >=3.0.2, <4.0.0",
-    "pyqt6 >=6.7.0, <7.0.0",
-    "pyqtgraph",
+  # nested deps-groups
+  # https://docs.astral.sh/uv/concepts/projects/dependencies/#nesting-groups
+  {include-group = 'uis'},
+  {include-group = 'repl'},
+  {include-group = 'testing'},
+  {include-group = 'de'},
 ]
 lint = [
   # XXX, with flake.nix needs to be from nixpkgs