What's new in the v0.8 line: Stacks, canonical roles, and voice end-to-end

Jul 4, 2026

The v0.8 line runs from v0.8.0-beta.1 (2026-06-21) through v0.8.4b1 (2026-07-04) — eleven cuts. The throughline is config as a single source of truth: Stacks, canonical roles, portable profiles, and a resolved-argv endpoint all collapse “what is this slot actually running” down to one answer instead of several that could disagree. Everything below traces to the changelog.

Stacks: declarative config as the SSOT

v0.8.0-beta.1 introduces Stacks — a StackConfig schema plus a StackApplyEngine that plan()s a Stack into a ChangeSet, apply_config()s it as an atomic commit with rollback, and converge()s the live slot set (primary-slot load/swap/skip plus capability-child routing through the orchestrator). Stacks carry content-hash drift detection and an active-stack pointer, export/import through a checksummed .hal0stack.json envelope, and a snapshot path that captures your live config back into a Stack. Three seed stacks — saber, forge, pi — ship derived from the roster bench. Later fixes in v0.8.2b2 and v0.8.3b1 round this out: absent stack models can now be pulled (curated HF coordinates were registered for the seed-stack GGUF builds), and apply flags unresolved profile/model refs and reports degraded rather than a false “clean” when a slot fails to load.

Alongside Stacks, v0.8.0-beta.1 also single-sources slot launch argv: a resolver dedups the flag soup into a last-wins canonical command, and per-flag provenance is exposed at GET /api/slots/{name}/resolved — the slot edit drawer renders the resolved command with source badges (base / profile / extra_args) so you can see exactly which layer set which flag.

Canonical roles: `agent` and `utility` replace `chat` and `primary`

v0.8.0-beta.3 establishes two canonical LLM roles: agent (the capable default and dispatch fallback anchor, replacing chat) and utility (a cheap helper now seeded on every install, so extraction work no longer silently falls back to a heavy model). Any enabled type=llm slot is addressable as hal0/<slot>, and the advertised canonical virtuals are hal0/agent, hal0/utility, hal0/npu.

This work also finishes removing Cognee: Hindsight is now the only memory engine, with a PgVector boot-degrade fallback.

Voice, end-to-end

v0.8.0-beta.1 brings up the voice stack for real — voice_wire fixed, Open WebUI Call mode wired, and the NPU-trio facade auto-provisioning STT. v0.8.2b3 completes the picture on the synthesis side: a new Qwen3TTSProvider serves Qwen3-TTS from the canonical tts slot, and the voice.tts capability is a single switch that swaps the engine between Kokoro-82M (CPU) and Qwen3-TTS (GPU) — no separate slot to configure, no reconfiguration step. That release also ships a GPU benchmark harness (hal0-benchctl) and a standalone-to-slot migration runbook for anyone running an older Qwen3-TTS setup outside of hal0.

Portable profiles

v0.8.2b1 gives profiles the same sharing model Stacks already had: export to a self-contained, checksummed .hal0profile.json envelope and import it on another host. New routes (GET /api/profiles/{name}, POST /api/profiles/{name}/export, POST /api/profiles/import) and matching MCP tools (profile_export is autonomous; profile_import/profile_delete are gated) mirror the stack_* set. The dashboard adds an Export button to every profile card and an Import dialog with a dry-run preview before commit.

v0.8.3b1: the 72-finding reliability sweep

v0.8.3b1 is a large reliability and completeness release — a 72-finding platform review remediated in eight verified waves, each regression-tested and gated by CI + Playwright. The user-visible defaults change too: the dashboard now shows Power & Thermal (live GPU clock/temp/power) and Per-Slot Throughput cards by default, disabling a capability actually stops it serving, and the bge reranker is finally classified and routed as a reranker instead of chat.

Underneath:

Interrupted pulls resume via HTTP Range/If-Range instead of restarting from zero, with the on-disk prefix re-hashed so the final SHA-256 stays exact.
Disk-space preflight fails fast with a structured model.insufficient_disk error before a multi-GB pull can fill the disk.
Host-memory-pressure LRU eviction unloads idle slots under pressure.
Cross-process safety — advisory file locks around registry and capability writes, plus parent-directory fsync after atomic writes.
Every backend-supported field the API already accepted (capabilities, backends, rope_freq_base, mmproj, hf_repo/hf_filename, per-slot vision, NPU asr/embed) is now exposed in the edit drawers.

v0.8.4b1: models, logs, and memory

The current cut, v0.8.4b1, is a safe, additive follow-up. A registry model can now declare a preferred runtime profile (defaults.profile) that a slot adopts on create and on every model swap, gated on device/type compatibility. The Models view gets a dedicated Image/ComfyUI toggle, and image-gen models are correctly tagged and grouped by their on-disk category. The slot edit drawer’s context field finally seeds from the persisted context_size instead of the live runtime metric or a hardcoded 16k, so a cold reload or model swap no longer clobbers your configured context window. Logs and events are unified into one surface with real source/slot attribution, and memory gains a durable audit trail for every destructive op — bank, memory, config, document, directive, operation, and mental-model deletes are now attributable after the fact — plus a response-shape guard so upstream drift surfaces as a loud error instead of a silently blank console panel.

Hermes durable memory, on by default

v0.8.1-beta.1 makes cross-session recall a zero-config default: a fresh hal0 agent bootstrap hermes now provisions a working hal0-memory provider automatically, backed by two banks — private:hermes (default) and shared (cross-agent) — through hal0’s Hindsight engine. The agent gets hal0_memory_{search,recall,add} tools and auto-injects recalled context each turn with no manual config.

Next: v0.9

The v0.8 beta line has been an unusually long run of consolidation — Stacks, canonical roles, voice, portable profiles, and a 72-finding reliability sweep, capped by v0.8.2b4’s docs re-baseline against that current reality. v0.9 took everything landed across these betas and stabilized it into the next line; 1.0.0 followed. See the changelog for what shipped since.

Try it

curl -fsSL https://hal0.dev/install.sh | bash

Already running an older line? hal0 update --channel stable (or nightly), and hal0 update --rollback reverts atomically. Full notes on the releases page and the update and rollback guide.