diff --git a/stacks/csm/.env.example b/stacks/csm/.env.example
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+# Sesame CSM stack tunables. Copy to `.env` on irv-ml1 before deploying.
+
+# ── build pin ────────────────────────────────────────────────────────
+# SHA of phildougherty/sesame_csm_openai. Use the FULL 40-char SHA;
+# `main` works but is NOT reproducible — pin before relying on it.
+#   https://github.com/phildougherty/sesame_csm_openai/commits/main
+CSM_SHA=main
+
+# Local image tag — bump to force a fresh layer build.
+CSM_TAG=v1
+
+# ── network ──────────────────────────────────────────────────────────
+# Host port. Container listens on 8000 internally.
+# Reserved on irv-ml1: 8188 ComfyUI, 8190 CosyVoice, 8191 Qwen3-TTS,
+# 8192 IndexTTS-2, 8193 Kokoro, 8194 VibeVoice, 8195 Fish-S2,
+# 8196 Chatterbox, 8197 Voxtral, 8198 Kyutai, 8199 Zonos, 8200 Dia,
+# 8765 Parakeet. 8201 picked here.
+CSM_PORT=8201
+
+# Bind address. 0.0.0.0 exposes on all interfaces (incl. the WG tunnel
+# interface 10.100.79.3); 127.0.0.1 restricts to local-only.
+CSM_BIND=0.0.0.0
+
+# ── runtime / GPU ────────────────────────────────────────────────────
+# Devices visible inside the container. "0" pins to the RTX 3090
+# (24 GB) — CSM-1B (~8 GB) fits; use "1" for the A6000.
+CSM_GPU_DEVICES=0
+
+# Optional HF device_map for multi-GPU: auto | balanced | sequential.
+# Leave empty for single-GPU (the common case here).
+CSM_DEVICE_MAP=
+
+# ── secrets ──────────────────────────────────────────────────────────
+# REQUIRED. sesame/csm-1b is a GATED model: accept its license at
+#   https://huggingface.co/sesame/csm-1b
+# then paste a HF token (read scope) here. Without it, first-boot model
+# download 401s. This file is .env.example (committed) — put the REAL
+# token only in the .env on the host, which is gitignored.
+CSM_HF_TOKEN=
+
+# ── persistent storage on the host ───────────────────────────────────
+# Voices dir — cloned/custom voice samples the wrapper serves by ID.
+# Included in restic (clones need the original sample to recreate).
+CSM_VOICES_DIR=/worktank/csm/voices
+
+# HuggingFace cache — csm-1b + Llama-3.2-1B tokenizer + Mimi land here
+# on first start. Bind-mounted to survive recreate. Excluded from restic
+# (regenerable from HF, given the token + license acceptance).
+CSM_CACHE_DIR=/worktank/csm/cache
diff --git a/stacks/csm/README.md b/stacks/csm/README.md
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+# Sesame CSM
+
+Sesame's **Conversational Speech Model** (the engine behind the
+"Maya/Miles" demo) — a context-aware speech generator (Llama backbone +
+Mimi audio codec) — served via
+[phildougherty/sesame_csm_openai](https://github.com/phildougherty/sesame_csm_openai),
+an OpenAI-compat wrapper.
+
+**Server:** irv-ml1 (Irvine, WireGuard-only)
+**Port:** 8201 (container listens on 8000)
+**GPUs:** pins to device 0 (RTX 3090) by default; ~8 GB VRAM
+**Image:** `local/csm:v1` — built locally from a pinned git SHA of the
+wrapper via docker buildx's git URL context
+**Upstream wrapper:** [phildougherty/sesame_csm_openai](https://github.com/phildougherty/sesame_csm_openai) (MIT)
+**Upstream model:** [sesame/csm-1b](https://huggingface.co/sesame/csm-1b)
+(**gated** — Sesame's own license) + `unsloth/Llama-3.2-1B` tokenizer + Mimi codec
+
+## Why this stack exists — and what it is *not*
+
+CSM is a **conversational** speech model, not a plain reader. It
+conditions on prior conversation turns (text **and** audio) to choose
+prosody and tone — it's designed to be the **speech layer of a voice
+agent**, where a separate LLM produces the words and CSM voices them
+with context-aware delivery.
+
+- As **pure TTS** it works standalone (OpenAI-compat
+  `POST /v1/audio/speech`, voices `alloy/echo/fable/onyx/nova/shimmer`
+  plus cloned IDs).
+- Its real edge — contextual prosody across turns — only pays off in
+  **interactive / voice-agent** use, not monologue narration. For
+  skaldsong's *reader*, the emotive single-voice engines (Fish S2-Pro,
+  IndexTTS-2) and Dia (dialogue) remain the better fits; CSM is here for
+  voice-agent experiments.
+
+## ⚠️ Gated model — token required before first boot
+
+`sesame/csm-1b` is gated. Before deploying:
+
+1. Accept the license at <https://huggingface.co/sesame/csm-1b>.
+2. Put a HF token (read scope) in `CSM_HF_TOKEN` in the host `.env`
+   (never in `.env.example`).
+
+Without it the first-boot model download 401s.
+
+## Deploy
+
+```bash
+# from this workstation (irv-ml1 is WG-only — routes via ana-wg):
+scripts/deploy-stack.sh irv-ml1 csm
+# then on irv-ml1, first run builds from the pinned SHA:
+#   docker compose up -d --build
+```
+
+First boot pulls csm-1b + the Llama-3.2-1B tokenizer + Mimi into
+`CSM_CACHE_DIR`; the 600 s `start_period` covers it.
+
+## Notes
+
+- **Pin `CSM_SHA`** to a full 40-char commit before relying on this —
+  `.env.example` ships `main`, which is not reproducible.
+- The wrapper can also serve Dia-1.6B, but we run Dia from its own
+  [`dia`](../dia/) stack — keep this one CSM-only to avoid overlap.
+- Endpoints: `/v1/audio/speech` (OpenAI-compat), `/v1/audio/voices`,
+  `/v1/audio/models`. No dedicated `/health` route — the healthcheck
+  probes `/v1/audio/voices` (only answers once the model is loaded).
diff --git a/stacks/csm/compose.yaml b/stacks/csm/compose.yaml
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+# Sesame CSM-1B (Conversational Speech Model) served via
+# phildougherty/sesame_csm_openai — an OpenAI-compat wrapper around
+# Sesame's context-aware speech model (Llama backbone + Mimi codec).
+#
+# Why this stack exists alongside the other TTS:
+#   * CSM is a CONVERSATIONAL speech layer, not a plain reader — it
+#     conditions on prior turns (text + audio) to pick prosody, built
+#     for voice-AGENT turn-taking. As pure TTS it works standalone;
+#     its differentiator only pays off in interactive/agent use.
+#   * OpenAI-compat /v1/audio/speech with 6 standard voices
+#     (alloy/echo/fable/onyx/nova/shimmer) + cloned voice IDs.
+#   * ~8 GB VRAM; fits the 3090 (device 0) or A6000 (device 1).
+#
+# NOTE: sesame/csm-1b is a GATED model — you must accept its license at
+# https://huggingface.co/sesame/csm-1b and supply CSM_HF_TOKEN in .env
+# before first boot, or the model download 401s.
+#
+# Image built locally from the upstream wrapper via buildx git-context.
+# All tunables live in .env — edit that, not this file.
+
+services:
+  csm:
+    image: local/csm:${CSM_TAG}
+    build:
+      context: https://github.com/phildougherty/sesame_csm_openai.git#${CSM_SHA}
+      dockerfile: Dockerfile
+    container_name: csm
+    restart: unless-stopped
+    runtime: nvidia
+    ports:
+      - "${CSM_BIND:-0.0.0.0}:${CSM_PORT}:8000"
+    environment:
+      - NVIDIA_VISIBLE_DEVICES=${CSM_GPU_DEVICES:-0}
+      - NVIDIA_DRIVER_CAPABILITIES=compute,utility
+      # Required: gated-model access token (accept the csm-1b license on
+      # HF first). Set the real value in .env, NEVER here.
+      - HF_TOKEN=${CSM_HF_TOKEN}
+      - HF_HUB_ENABLE_HF_TRANSFER=1
+      - HF_HOME=/app/hf_cache
+      # Optional multi-GPU split: auto | balanced | sequential.
+      - CSM_DEVICE_MAP=${CSM_DEVICE_MAP:-}
+    volumes:
+      - ${CSM_VOICES_DIR}:/app/voices
+      - ${CSM_CACHE_DIR}:/app/hf_cache
+    healthcheck:
+      # The wrapper exposes no /health route; GET /v1/audio/voices
+      # returns the voice list only once the model is loaded, so it
+      # doubles as liveness + ready. python urllib (no curl in image),
+      # bound to 127.0.0.1 (uvicorn is IPv4-only).
+      test: ["CMD-SHELL", "python3 -c \"import urllib.request,sys; urllib.request.urlopen('http://127.0.0.1:8000/v1/audio/voices', timeout=5); sys.exit(0)\""]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+      # First boot pulls csm-1b + the Llama-3.2-1B tokenizer + Mimi —
+      # gated download, generous deadline.
+      start_period: 600s
+    labels:
+      - homepage.group=AI Systems
+      - homepage.name=Sesame CSM
+      - homepage.icon=mdi-account-voice-outline
+      - homepage.description=Conversational speech model — context-aware voice-agent TTS (irv-ml1)
+      - homepage.href=http://10.100.79.3:${CSM_PORT}