feat(core): PAM system-user authentication backend

.github/workflows/cache-warm.yml

@@ -46,6 +46,9 @@ jobs:
             os: macos-latest
           # - target: x86_64-apple-darwin
           #   os: macos-latest
+          - target: x86_64-unknown-linux-gnu
+            os: ubuntu-latest
+            pam: true
     steps:
       - uses: actions/checkout@v6
 
@@ -57,6 +60,10 @@ jobs:
         if: runner.os == 'macOS'
         run: brew install protobuf
 
+      - name: Install libpam dev headers (PAM build)
+        if: ${{ matrix.pam }}
+        run: sudo apt-get update && sudo apt-get install -y libpam0g-dev
+
       - name: Install Rust stable
         uses: dtolnay/rust-toolchain@stable
         with:
@@ -73,3 +80,9 @@ jobs:
       # re-saving), but the restore still refreshes the eviction timer.
       - name: Build release dependencies
         run: cargo build --release --workspace --bins --target ${{ matrix.target }}
+
+      # Warm the PAM-only dependency (pam-sys) so the release run's PAM rebuild
+      # restores from cache too.
+      - name: Build PAM dependencies
+        if: ${{ matrix.pam }}
+        run: cargo build --release -p agentd-core --features pam --target ${{ matrix.target }}

.github/workflows/ci.yml

@@ -190,6 +190,44 @@ jobs:
       - name: Run Docker integration tests (orchestrator)
         run: cargo test -p orchestrator -- --ignored --test-threads=1
 
+  pam-feature:
+    name: PAM feature build (${{ matrix.os }})
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [macos-latest, ubuntu-latest]
+    steps:
+      - uses: actions/checkout@v6
+
+      - name: Install protoc and libpam (Linux)
+        if: runner.os == 'Linux'
+        run: sudo apt-get update && sudo apt-get install -y protobuf-compiler libpam0g-dev
+
+      - name: Install protoc (macOS)
+        if: runner.os == 'macOS'
+        run: brew install protobuf
+
+      - name: Install Rust stable
+        uses: dtolnay/rust-toolchain@stable
+        with:
+          components: clippy
+
+      - uses: Swatinem/rust-cache@v2
+        with:
+          key: pam-feature-${{ matrix.os }}
+
+      # The `pam` feature links the system PAM library and builds on both
+      # Linux (Linux-PAM) and macOS (OpenPAM). Build + clippy keep the
+      # feature-gated code compiling on each. The verifier's runtime behavior
+      # needs a live PAM stack and is exercised by the `--ignored` pam_smoke
+      # tests (see docs/pam-authentication.md).
+      - name: Build agentd-core with PAM
+        run: cargo build -p agentd-core --features pam
+
+      - name: Clippy agentd-core with PAM
+        run: cargo clippy -p agentd-core --features pam --all-targets -- -D warnings
+
   audit:
     name: Security Audit
     runs-on: ubuntu-latest

.github/workflows/release.yml

@@ -51,6 +51,15 @@ jobs:
           # (1h+ builds) that cross-compiling beats building natively.
           # - target: x86_64-apple-darwin
           #   os: macos-latest
+          # Dynamically-linked glibc build with PAM (system-user login) compiled
+          # in, shipped as a separate `-pam` tarball. PAM `dlopen`s its modules
+          # at runtime, which the static musl targets above cannot do — so a PAM
+          # artifact must be a glibc build. The default install stays musl/no-PAM;
+          # this is opt-in (install.sh AGENTD_PAM=1). glibc reduces portability:
+          # it requires a glibc at least as new as the runner's.
+          - target: x86_64-unknown-linux-gnu
+            os: ubuntu-latest
+            pam: true
     steps:
       - uses: actions/checkout@v6
         with:
@@ -64,6 +73,11 @@ jobs:
         if: runner.os == 'macOS'
         run: brew install protobuf
 
+      # The `pam` feature links libpam, so the dev headers must be present.
+      - name: Install libpam dev headers (PAM build)
+        if: ${{ matrix.pam }}
+        run: sudo apt-get update && sudo apt-get install -y libpam0g-dev
+
       - name: Install Rust stable
         uses: dtolnay/rust-toolchain@stable
         with:
@@ -81,6 +95,13 @@ jobs:
       - name: Build release binaries
         run: cargo build --release --workspace --bins --target ${{ matrix.target }}
 
+      # Opt-in: overwrite agentd-core with a PAM-enabled build. Done as a
+      # separate `-p agentd-core` build (not a workspace `--features`) since the
+      # `pam` feature only exists on that crate — mirrors `cargo xtask`.
+      - name: Rebuild agentd-core with PAM support
+        if: ${{ matrix.pam }}
+        run: cargo build --release -p agentd-core --features pam --target ${{ matrix.target }}
+
       - name: Download UI assets
         uses: actions/download-artifact@v4
         with:
@@ -98,6 +119,9 @@ jobs:
           set -euo pipefail
           TARGET="${{ matrix.target }}"
           VERSION="${{ github.ref_name }}"
+          # PAM builds ship under a distinct `-pam` suffix so they sit alongside
+          # the default (musl/no-PAM) artifact rather than replacing it.
+          SUFFIX="${{ matrix.pam && '-pam' || '' }}"
           BINS=(
             agentd-ask
             agentd-communicate
@@ -119,12 +143,12 @@ jobs:
           cp "target/${TARGET}/release/cli" "stage/agent"
           chmod 755 stage/agent stage/agentd-*
           mkdir -p dist
-          tar -czf "dist/agentd-${VERSION}-${TARGET}.tar.gz" -C stage .
+          tar -czf "dist/agentd-${VERSION}-${TARGET}${SUFFIX}.tar.gz" -C stage .
 
       - name: Upload artifacts
         uses: actions/upload-artifact@v4
         with:
-          name: tarball-${{ matrix.target }}
+          name: tarball-${{ matrix.target }}${{ matrix.pam && '-pam' || '' }}
           path: dist/*.tar.gz
           if-no-files-found: error
 

Makefile

@@ -6,11 +6,25 @@
 #   make test              Run all tests
 #   make docker-build-claude  Build the Claude Code Docker image locally
 
-.PHONY: help build test clippy fmt fmt-fix docker-build-claude docker-build-claude-multiarch docker-run-claude
+.PHONY: help build test clippy fmt fmt-fix \
+	build-release build-ui \
+	install-user install-user-pam install-system install-system-pam \
+	uninstall-user uninstall-system \
+	docker-build-claude docker-build-claude-multiarch docker-run-claude
 
 # Default image name — matches the DEFAULT_IMAGE constant in crates/wrap/src/docker.rs
 CLAUDE_IMAGE ?= agentd-claude:latest
 
+# Set PAM=1 to compile agentd-core with system-user (PAM) login support.
+# macOS needs no extra packages; on Linux install the PAM dev headers first
+# (libpam0g-dev on Debian/Ubuntu, pam-devel on RHEL/Fedora).
+PAM ?= 0
+
+# Freshly-built CLI binary. It is the workspace bin `cli`; the installer renames
+# it to `agent` on install. The installed `agent` (on PATH) is used to uninstall.
+CLI_BIN := target/release/cli
+UI_DIST := ui/dist
+
 help: ## Show this help message
 	@grep -E '^[a-zA-Z_-]+:.*?## .*$$' $(MAKEFILE_LIST) | \
 		awk 'BEGIN {FS = ":.*?## "}; {printf "  \033[36m%-24s\033[0m %s\n", $$1, $$2}'
@@ -32,6 +46,51 @@ fmt: ## Check formatting
 fmt-fix: ## Auto-fix formatting
 	cargo fmt --all
 
+# ── Install ──────────────────────────────────────────────────────────
+#
+# Four supported flows (all build from source, then run `agent install`):
+#
+#   make install-user           # per-user install   (intended for macOS dev)
+#   make install-user-pam       #    … with PAM login
+#   make install-system         # system-wide install (intended for Linux)
+#   make install-system-pam     #   … with PAM login
+#
+# PAM=1 also works on the base targets, e.g. `make install-user PAM=1`.
+#
+# PAM caveats:
+#   - Linux needs the PAM dev headers at build time (see PAM var above).
+#   - A Linux system install is what lets core verify other users' passwords;
+#     for real PAM auth its service account must also be in the `shadow` group
+#     (or use an SSSD stack). See docs/pam-authentication.md.
+
+build-release: ## Build release binaries (PAM=1 compiles agentd-core with PAM)
+	cargo build --release --workspace --bins
+	@if [ "$(PAM)" = "1" ]; then \
+		echo "==> Rebuilding agentd-core with PAM support (libpam dev headers required on Linux)"; \
+		cargo build --release -p agentd-core --features pam; \
+	fi
+
+build-ui: ## Build the web UI assets (bun)
+	cd ui && bun install --frozen-lockfile && bun run build
+
+install-user: build-release build-ui ## Per-user install (macOS dev); PAM=1 for system-user login
+	$(CLI_BIN) install --user --bin-src target/release --ui-dir $(UI_DIST)
+
+install-system: build-release build-ui ## System-wide install (Linux); PAM=1 for system-user login
+	$(CLI_BIN) install --system --bin-src target/release --ui-dir $(UI_DIST)
+
+install-user-pam: ## Per-user install with PAM (macOS dev)
+	$(MAKE) install-user PAM=1
+
+install-system-pam: ## System-wide install with PAM (Linux)
+	$(MAKE) install-system PAM=1
+
+uninstall-user: ## Remove a per-user install (uses the installed `agent`)
+	agent uninstall --user
+
+uninstall-system: ## Remove a system-wide install (uses the installed `agent`)
+	agent uninstall --system
+
 # ── Docker ───────────────────────────────────────────────────────────
 
 docker-build-claude: ## Build the Claude Code agent Docker image locally

contrib/scripts/install.sh

@@ -13,6 +13,11 @@
 # Environment variables:
 #   AGENTD_VERSION  Install a specific version (e.g. "v0.5.0" or "0.5.0")
 #                   instead of the latest release.
+#   AGENTD_PAM      When set to 1/true/yes/on, install the PAM-enabled build
+#                   (system-user login). Only available as a prebuilt artifact
+#                   for Linux x86_64 (a dynamically-linked glibc tarball — the
+#                   static musl default cannot load PAM modules). On any other
+#                   platform, build from source with `--features pam` instead.
 #   PREFIX          Install prefix honoured by `agent install`
 #                   (default: /usr/local on macOS or as root, ~/.local otherwise).
 #
@@ -26,6 +31,15 @@ REPO="geoffjay/agentd"
 info() { printf '\033[0;34m==>\033[0m %s\n' "$1"; }
 error() { printf '\033[0;31merror:\033[0m %s\n' "$1" >&2; exit 1; }
 
+# Truthy test for opt-in flags, matching the AGENTD_PAM semantics used by the
+# Rust installer and config loader (1/true/yes/on, case-insensitive).
+is_truthy() {
+    case "$(printf '%s' "${1:-}" | tr '[:upper:]' '[:lower:]')" in
+        1 | true | yes | on) return 0 ;;
+        *) return 1 ;;
+    esac
+}
+
 # Map uname output to a release target triple.
 detect_target() {
     os=$(uname -s)
@@ -109,7 +123,23 @@ verify_checksum() {
 main() {
     target=$(detect_target)
     version=$(resolve_version)
-    asset="agentd-${version}-${target}.tar.gz"
+
+    # Opt-in PAM build. Only Linux x86_64 ships a prebuilt PAM artifact: it is a
+    # dynamically-linked glibc tarball (`-pam` suffix, target
+    # x86_64-unknown-linux-gnu), because the static musl default cannot dlopen
+    # PAM modules. Any other platform must build from source.
+    suffix=""
+    if is_truthy "${AGENTD_PAM:-}"; then
+        if [ "$target" = "x86_64-unknown-linux-musl" ]; then
+            target="x86_64-unknown-linux-gnu"
+            suffix="-pam"
+        else
+            error "AGENTD_PAM is only available as a prebuilt artifact for Linux x86_64 (glibc).
+For this platform ($(uname -s)/$(uname -m)), build from source with: cargo build -p agentd-core --features pam"
+        fi
+    fi
+
+    asset="agentd-${version}-${target}${suffix}.tar.gz"
     base="https://github.com/$REPO/releases/download/$version"
 
     # Explicit template: unlike `mktemp -d` bare, this honours $TMPDIR on

crates/cli/src/commands/config.rs

@@ -331,7 +331,6 @@ monitor_url      = "http://localhost:17003"
 memory_url       = "http://localhost:17008"
 communicate_url  = "http://localhost:17010"
 knowledge_url    = "http://localhost:17011"
-index_url        = "http://localhost:17012"
 
 # ---------------------------------------------------------------------------
 # [services.mcp] — MCP server (no dedicated port — uses stdio transport)

crates/cli/src/commands/memory.rs

@@ -511,8 +511,9 @@ async fn list(
             ]));
 
             for mem in &response.items {
-                let content_preview = if mem.content.len() > 50 {
-                    format!("{}…", &mem.content[..49])
+                let content_preview = if mem.content.chars().count() > 50 {
+                    let truncated: String = mem.content.chars().take(49).collect();
+                    format!("{truncated}…")
                 } else {
                     mem.content.clone()
                 };