chore: enhance flampy dependencies.

docker/Dockerfile.console

@@ -20,18 +20,31 @@ RUN /usr/local/cargo/bin/flmadm install \
     --skip-build \
     --force
 
+# Install Python 3.12 via uv to match runtime (ubuntu:24.04)
+# Then pre-warm uv cache for flamepy dependencies in the builder
+# This avoids network access during runtime container startup
+RUN /usr/bin/uv python install 3.12 && \
+    UV_CACHE_DIR=/usr/local/flame/data/cache/uv \
+    UV_LINK_MODE=copy \
+    /usr/bin/uv run --python 3.12 \
+    --find-links /usr/local/flame/wheels \
+    --with pip \
+    --with flamepy \
+    python -c "import flamepy; print('flamepy cache warmed in builder')"
+
 FROM ubuntu:24.04
 
 RUN apt-get update && apt-get install -y wget vim iputils-ping ssh curl python3 python3-pip && rm -rf /var/lib/apt/lists/*
 
-# Copy the entire installation from builder (including uv in bin/)
+# Copy the entire installation from builder (including uv in bin/ and pre-warmed cache)
 COPY --from=builder /usr/local/flame /usr/local/flame
 
 # Add flame binaries to PATH (includes uv)
 ENV PATH="/usr/local/flame/bin:${PATH}"
 ENV FLAME_HOME=/usr/local/flame
 
 # Install flamepy and pytest for test client using uv from FLAME_HOME
-RUN /usr/local/flame/bin/uv pip install --system --break-system-packages --no-cache /usr/local/flame/sdk/python pytest
+# Use UV_LINK_MODE=copy for cross-filesystem compatibility
+RUN UV_LINK_MODE=copy /usr/local/flame/bin/uv pip install --system --break-system-packages --no-cache /usr/local/flame/sdk/python pytest
 
 CMD ["service", "ssh", "start", "-D"]

docker/Dockerfile.fem

@@ -21,13 +21,25 @@ RUN /usr/local/cargo/bin/flmadm install \
     --skip-build \
     --force
 
+# Install Python 3.12 via uv to match runtime (ubuntu:24.04)
+# Then pre-warm uv cache for flamepy dependencies in the builder
+# This avoids network access during runtime container startup
+RUN /usr/bin/uv python install 3.12 && \
+    UV_CACHE_DIR=/usr/local/flame/data/cache/uv \
+    UV_LINK_MODE=copy \
+    /usr/bin/uv run --python 3.12 \
+    --find-links /usr/local/flame/wheels \
+    --with pip \
+    --with flamepy \
+    python -c "import flamepy; print('flamepy cache warmed in builder')"
+
 FROM ubuntu:24.04
 
 RUN apt-get update && apt-get install -y python3-pip git && rm -rf /var/lib/apt/lists/*
 
 WORKDIR /usr/local/flame/work
 
-# Copy the entire installation from builder (including uv in bin/)
+# Copy the entire installation from builder (including uv in bin/ and pre-warmed cache)
 COPY --from=builder /usr/local/flame /usr/local/flame
 
 ENV FLAME_HOME=/usr/local/flame

executor_manager/src/shims/host_shim.rs

@@ -272,9 +272,14 @@ impl HostShim {
         };
 
         let work_dir = cur_dir.clone();
-        // Setup working directory and get environment overrides
+        // Setup working directory and get environment defaults
+        // Use entry().or_insert() so application-specific envs take precedence over defaults
+        // This allows applications like flmrun to specify UV_CACHE_DIR pointing to
+        // the pre-cached directory instead of using a per-instance empty cache
         let wd_envs = Self::setup_working_directory(&work_dir)?;
-        envs.extend(wd_envs);
+        for (key, value) in wd_envs {
+            envs.entry(key).or_insert(value);
+        }
 
         let log_out = OpenOptions::new()
             .create(true)

flmadm/src/managers/installation.rs

@@ -242,10 +242,11 @@ impl InstallationManager {
 
         let uv_cache_dir = paths.cache.join("uv");
 
-        // Install flamepy and dependencies to populate the cache
-        // Using --target to a temp directory avoids needing a venv
+        // Phase 1: Cache flamepy and all its dependencies (grpcio, protobuf, cloudpickle, etc.)
+        // Using --target to a temp directory to populate the cache without needing a venv
         let cache_target = paths.work.join(".flamepy-cache-target");
-        fs::create_dir_all(&cache_target).context("Failed to create temporary directory for caching")?;
+        fs::create_dir_all(&cache_target)
+            .context("Failed to create temporary directory for caching")?;
 
         let install_output = std::process::Command::new(&uv_path)
             .arg("pip")
@@ -255,7 +256,7 @@ impl InstallationManager {
             .arg("--find-links")
             .arg(&paths.wheels)
             .arg("flamepy")
-            .arg("pip") // Also cache pip as it's used by flmrun
+            .arg("pip") // Also cache pip as it's used by flmrun for user packages
             .env("UV_CACHE_DIR", &uv_cache_dir)
             .output()
             .context("Failed to execute uv pip install")?;
@@ -271,7 +272,41 @@ impl InstallationManager {
                 stderr.lines().next().unwrap_or(&stderr)
             );
         } else {
-            println!("  ✓ Cached dependencies to: {}", uv_cache_dir.display());
+            println!(
+                "  ✓ Cached flamepy and dependencies to: {}",
+                uv_cache_dir.display()
+            );
+        }
+
+        // Phase 2: Pre-warm uv's ephemeral environment cache by running the exact command
+        // that flmrun uses at startup. This ensures all packages are cached in the format
+        // that 'uv run --with' expects (which differs from 'uv pip install').
+        println!("  🔄 Pre-warming uv run cache...");
+
+        // Create a simple Python script that just exits successfully
+        let run_output = std::process::Command::new(&uv_path)
+            .arg("run")
+            .arg("--find-links")
+            .arg(&paths.wheels)
+            .arg("--with")
+            .arg("pip")
+            .arg("--with")
+            .arg("flamepy")
+            .arg("python")
+            .arg("-c")
+            .arg("import sys; sys.exit(0)")
+            .env("UV_CACHE_DIR", &uv_cache_dir)
+            .output()
+            .context("Failed to execute uv run warmup")?;
+
+        if !run_output.status.success() {
+            let stderr = String::from_utf8_lossy(&run_output.stderr);
+            println!(
+                "  ⚠️  Failed to pre-warm uv run cache (will warm at runtime): {}",
+                stderr.lines().next().unwrap_or(&stderr)
+            );
+        } else {
+            println!("  ✓ Pre-warmed uv run cache");
         }
 
         Ok(())