careless: build venv with uv instead of conda (anaconda.com blocked on Ra)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

careless/README.md

@@ -8,17 +8,20 @@ inference (variational merging), built on TensorFlow.
 
 ## How it is built
 
-The build installs a private miniconda into `$PREFIX/miniconda`, creates a
-`careless_<version>` env with Python 3.12 (upstream supports >=3.9,<3.13),
-and runs `pip install careless[cuda]==<version>` inside it. The `[cuda]`
-extra pulls the NVIDIA libraries as pip wheels, so the same install works
-on GPU and CPU-only Ra nodes.
+Upstream recommends a fresh conda env, but repo.anaconda.com is not
+reachable from Ra, so the build uses uv instead: it fetches a standalone
+Python 3.12 into `$PREFIX/python` (upstream supports >=3.9,<3.13), creates
+`$PREFIX/venv`, and runs `uv pip install careless[cuda]==<version>` into
+it. The `[cuda]` extra pulls the NVIDIA libraries as pip wheels, so the
+same install works on GPU and CPU-only Ra nodes.
 
-Loading the module puts the env's `bin/` on `PATH` (the `careless` command
-is directly available, no `conda activate` needed) and sets `CARELESS_ENV`
-to the conda env path.
+`uv` must be on PATH on the build host (e.g. `pip install --user uv`).
+
+Loading the module puts the venv's `bin/` on `PATH` (the `careless`
+command is directly available, no activation needed) and sets
+`CARELESS_ENV` to the venv path.
 
 ## Adding a new version
 
 Add the version under `versions:` in `files/config.yaml`, then on a Ra
-login node: `./build <version>`.
+login node: `modbuild build <version>` (modbuild/2.1.2).

careless/build

@@ -5,12 +5,11 @@ pbuild::prep() {
 }
 
 pbuild::configure() {
-    # careless is pip-installed, but upstream recommends a fresh conda env
-    # (TensorFlow dependency conflicts), so install a private miniconda in PREFIX
-    mkdir -p "$PREFIX/miniconda"
-    wget https://repo.anaconda.com/miniconda/Miniconda3-latest-Linux-x86_64.sh -O "$PREFIX/miniconda/miniconda.sh"
-    bash "$PREFIX/miniconda/miniconda.sh" -b -u -p "$PREFIX/miniconda/"
-    "$PREFIX/miniconda/condabin/conda" create -y -n "careless_$V" python=3.12
+    # repo.anaconda.com is unreachable from Ra (GnuTLS error), so no conda.
+    # uv fetches a standalone CPython instead; keep it inside PREFIX so the
+    # venv's interpreter symlinks don't depend on the builder's home cache.
+    export UV_PYTHON_INSTALL_DIR="$PREFIX/python"
+    uv venv --python 3.12 "$PREFIX/venv"
 }
 
 pbuild::compile() {
@@ -18,10 +17,6 @@ pbuild::compile() {
 }
 
 pbuild::install() {
-    source "$PREFIX/miniconda/etc/profile.d/conda.sh"
-    conda activate "careless_$V"
-    pip install --upgrade pip
     # [cuda] extra ships the NVIDIA libs via pip wheels; works on CPU-only nodes too
-    pip install --no-cache-dir "careless[cuda]==${V_PKG}"
-    conda deactivate
+    uv pip install --python "$PREFIX/venv/bin/python" "careless[cuda]==${V_PKG}"
 }

careless/modulefile

@@ -12,5 +12,5 @@ approximate Bayesian inference (TensorFlow). Installed with the
 back to CPU otherwise.
 "
 
-setenv          CARELESS_ENV    $PREFIX/miniconda/envs/careless_$V
-prepend-path    PATH            $PREFIX/miniconda/envs/careless_$V/bin
+setenv          CARELESS_ENV    $PREFIX/venv
+prepend-path    PATH            $PREFIX/venv/bin