diff --git a/.ci/end2end/Dockerfile b/.ci/end2end/Dockerfile
index 4afd54fc..9bb8bf9a 100644
--- a/.ci/end2end/Dockerfile
+++ b/.ci/end2end/Dockerfile
@@ -7,7 +7,7 @@ COPY scripts /scripts
 RUN /scripts/setup_firefox.sh \
  && /scripts/setup_chrome.sh  \
  && /scripts/setup_node.sh    \
- && apt install --yes tox git \
+ && apt install --yes pipx git \
 # using python docs as a source of some html test data
 # need to prevent dpkg from excluding doc files...
  && sed -i '/usr.share.doc/d' /etc/dpkg/dpkg.cfg.d/excludes && apt install --yes python3-doc \
diff --git a/.ci/end2end/scripts/build_and_run_tests.sh b/.ci/end2end/scripts/build_and_run_tests.sh
index 7dcb591a..2db90b78 100755
--- a/.ci/end2end/scripts/build_and_run_tests.sh
+++ b/.ci/end2end/scripts/build_and_run_tests.sh
@@ -12,4 +12,8 @@ cp -R -T /promnesia_source /promnesia
 extension/.ci/build
 
 git init  # todo ??? otherwise setuptools-scm fails to detect the version...
-python3 -m tox -e end2end -- "$@"
+
+# eh. kinda annoying to jump over so many venv layer here...
+# but docker runs as root and it doesn't like pip install uv now
+# even if you pass --break-system-packages, then subsequent uv invocation also fails
+pipx run uv tool run --with=tox-uv tox -e end2end -- "$@"
diff --git a/.ci/run b/.ci/run
index 38070f34..060a7de8 100755
--- a/.ci/run
+++ b/.ci/run
@@ -11,6 +11,8 @@ if ! command -v sudo; then
     }
 fi
 
+# --parallel-live to show outputs while it's running
+tox_cmd='run-parallel --parallel-live'
 if [ -n "${CI-}" ]; then
     # install OS specific stuff here
     # TODO: pyjq is not necessary anymore? will keep CI deps just in case I guess
@@ -25,7 +27,8 @@ if [ -n "${CI-}" ]; then
         ;;
     cygwin* | msys* | win*)
         # windows
-        :
+        # ugh. parallel stuff seems super flaky under windows, some random failures, "file used by other process" and crap like that
+        tox_cmd='run'
         ;;
     *)
         # must be linux?
@@ -44,5 +47,9 @@ if ! command -v python3 &> /dev/null; then
     PY_BIN="python"
 fi
 
-"$PY_BIN" -m pip install --user tox
-"$PY_BIN" -m tox --parallel --parallel-live "$@"
+
+# TODO hmm for some reason installing uv with pip and then running
+# "$PY_BIN" -m uv tool fails with missing setuptools error??
+# just uvx directly works, but it's not present in PATH...
+"$PY_BIN" -m pip install --user pipx
+"$PY_BIN" -m pipx run uv tool run --with=tox-uv tox $tox_cmd "$@"
diff --git a/tox.ini b/tox.ini
index 260df645..1c7f680b 100644
--- a/tox.ini
+++ b/tox.ini
@@ -26,9 +26,9 @@ passenv =
     WITH_BROWSER_TESTS
     # todo ugh this is all so confusing... need to simplify
 usedevelop = true  # for some reason tox seems to ignore "-e ." in deps section??
-# note: --use-pep517 here is necessary for tox --parallel flag to work properly
-# otherwise it seems that it tries to modify .eggs dir in parallel and it fails
-install_command = {envpython} -m pip install --use-pep517 {opts} {packages}
+setenv =
+    HPI_MODULE_INSTALL_USE_UV=true
+uv_seed = true  # seems necessary so uv creates separate venvs per tox env?
 
 
 [testenv:ruff]
@@ -54,6 +54,7 @@ commands =
 [testenv:tests-all]
 deps =
     -e .[testing,all,HPI,org]
+    uv  # for hpi module install
 commands =
     # used in some tests
     {envpython} -m my.core module install \
@@ -70,6 +71,7 @@ setenv =
     PYTEST_TIMEOUT=120
 deps =
     -e .[testing,HPI]
+    uv  # for hpi module install
 commands =
     {envpython} -m my.core module install my.hypothesis
     {envpython} -m pytest     \
@@ -83,6 +85,7 @@ commands =
 [testenv:mypy-core]
 deps =
     -e .[testing]
+    uv  # for hpi module install
 commands =
     {envpython} -m mypy --install-types --non-interactive \
         # note: sources are tested separately, below
@@ -96,6 +99,7 @@ commands =
 [testenv:mypy-misc]
 deps =
     -e .[testing,HPI,org]  # todo install from HPI[all] or something?
+    uv  # for hpi module install
 commands =
     {envpython} -m my.core module install \
         my.github.ghexport                \