What's new in 0.21.0

A note on names (2026-09-21): the 0.21 line shipped to npm as 0.21.0-beta.1 through 0.21.0-beta.5. We have dropped the beta naming — Bazilion is and remains alpha until a deliberate 1.0 beta, so these releases are described here as 0.21.0. 0.21.0 final is published from the same commit as beta.5; the installed code is identical either way.

Bazilion 0.21 retired the alpha database contract: since the first 0.21 release, Bazilion migrates your database forward on startup and keeps a verified snapshot of the previous state beside it — no schema change costs you your home any more. The second release hardened the platforms; the third made failure modes visible; the fourth gated security in CI and documented home growth; the fifth is the UI consistency sweep — every surface degrades well.

Bazilion remains alpha: feature checkpoints ship as plain 0.N.0 versions, and a 1.0.0-beta.1 label is reserved for a deliberate, later decision.

The public packages bazilion, @bazilion/client and @bazilion/api-types move together. The bundled engine remains Pi 0.85.1.

Beta.5 — every surface degrades well

The coding sequence added roughly ten screens after the v0.14 UI hardening pass, and the audit found they degraded differently: a dead daemon could surface a developer-grade error screen. Two router-level defaults changed that for every route at once — a calm recovery state (what happened, retry, a safe exit; nothing substituted for the missing data) and a marked loading state during navigation. The coding surfaces also name themselves in the error (“Specialist verification unavailable”), and cancel-verification now requires a confirmation stating the consequence. A browser-acceptance walk pins the result: desktop and narrow viewports with overflow assertions, fresh-home empty states, then a real daemon-kill pass asserting the recovery state on every audited route.

En route, the sweep closed a CI gap: the web app was excluded from the typecheck that runs on every pull request — it is now included.

Beta.4 — the gate is not a convention

The BAZ-032 adversarial security suite — 153 required cases covering the daemon’s security boundaries — existed as a script that ran only at release time. A new security-acceptance CI job runs it on every pull request (~2 minutes, docker-free). The script fails closed: deleting or renaming a required case is itself a CI failure, so the manifest is the gate, not a convention.

Beta.4 also ships Growth and retention, the operator answer to “how big should a home be?”: coding evidence is bounded by design (7-day TTLs, a 256 MB home-wide budget, content-addressed snapshots that store paths and digests only), messages and sessions grow with use because they are the record, pre-migration snapshots are safe to delete once an upgrade is confirmed good, and logs/ is intentionally empty — the daemon writes no log files.

Beta.3 — no silent failure

Two silent failure modes were found and fixed, and every remaining recoverable failure mode is now pinned by a deterministic fault-injection test that asserts what the operator sees:

The queue stall after a daemon crash. A restart that interrupts queue processing pauses the Agent’s queue until you inspect and resume it — but nothing surfaced the pause: new messages were accepted and never drained, with no visible reason anywhere. A crash could make an Agent go permanently quiet. A new Attention kind, Paused queues, names the crash and the uncertain item count; resuming the queue clears it.
Opaque OAuth refresh failures. A revoked or expired ChatGPT refresh token surfaced the raw upstream error mid-turn. The error now says what to do: sign in again with bazilion auth openai login or the Connect button on /config.
Pinned by injection tests: provider outages retry boundedly then surface as trigger-failure attention items; Telegram delivery failures leave a terminal receipt while the underlying attention item stays open; message-loop breaches surface payload-free; a daemon kill mid-coding-run leaves an interrupted receipt with a reason; a failed backup is clean — no partial file, home and daemon intact.

Beta.3 also fixed a build race the CI matrix exposed: the web build and the CLI build (which bundles the web output) ran concurrently and could corrupt each other’s output.

Beta.2 — the CI matrix catches Windows and macOS

Test suites and a fresh-machine installer E2E now run on ubuntu, macOS and Windows on every PR, and the first runs caught six real defects:

Windows: every conversation write failed — fsync on a directory handle is not permitted there; the file fsync remains the durability floor.
Windows: bootstrap rotation failed — fsync on a read-only handle needs a write handle.
Windows followed symlinked session files despite the no-follow boundary; now rejected explicitly.
pnpm build matched no packages on Windows, so pnpm pack silently shipped an empty tarball — a Windows release would have published an empty npm package.
Symlinked BAZILION_HOME broke uninstall’s keep-the-root semantics.
Canonical-path identity guards rejected every worker spawn and session read on macOS.

The installer E2E runs the operator path on every PR — packed tarball → install → fresh-home bootstrap → provider setup → agent spawn → turn → clean uninstall, with no API key, no network egress and no Docker.

The platform boundary, stated

Linux is the validated platform. The workspace-claim identity is now portable (the same dev:ino semantics everywhere), but every agent turn also resolves repository context for the team root — and those content reads pin ancestry with Linux-only primitives, by design. Off-Linux, turns refuse with a clean, explicit safe_reads_unavailable response — the installer E2E asserts exactly that on macOS and Windows on every PR. Installing on macOS or Windows works (daemon, dashboard, setup); the first chat turn is where the wall is, and the error says so. Content-read portability is tracked as BAZ-057.

Homes upgrade in place

The headline is a contract, not a feature. Four rules now govern startup:

Migrations run forward, inside a transaction. Your applied migrations must be an unbroken prefix of the release’s migration chain; anything pending is applied on open. The applied set is recorded in a schema_migrations receipt ledger.
A snapshot precedes the first migration. Before touching an existing home, the daemon copies the live database to bazilion.pre-migration-<timestamp>.db beside it and integrity-checks the copy. If the snapshot cannot be produced or verified, nothing is migrated. A failed migration leaves the home on its previous schema and that snapshot is your recovery point.
A newer database is refused, not mutated. The schema version is stamped numerically; a database written by a newer release stops startup with upgrade guidance. Downgrades are unsupported — restore the pre-migration snapshot instead.
Unknown or historical homes still fail closed. A home from before this contract (0.19.x and earlier) is refused with recovery guidance and left untouched. Reset or restore, as before.

The upgrade path is proven, not asserted: CI seeds a real home with a real prior-release daemon and upgrades it, so v0.20.0 → beta.5 and each beta hop are exercised on every release. Read the upgrade procedure.

Give every device only what it needs

Until now any credential reached everything. Web tokens now carry scopes — read, write, approvals and admin — enforced per request, with a structured refusal that names the scope you are missing. The bootstrap credential from auth.json keeps implicit full access, browser sessions inherit their device’s scopes, and existing credentials were migrated to full access, so nothing changes until you choose to narrow one.

Mint narrow devices. bazilion token create --scope read for the wall tablet, --scope approvals for the phone that only answers questions, or the same choices on the tokens page.
Pair with one paste. bazilion token pair prints a bazilion-pair:// setup URL and QR code: it expires in ten minutes, works once, and admits exactly one credential exchange — a short-lived key that hands out a durable device identity. It is not itself an API credential.
Ask the server what it expects. GET /api/health now reports the auth posture — whether the gate is on, which credential kinds are accepted, and whether first-run setup is complete — so a client that cannot connect can tell you why.

Two half-finished surfaces removed

The Expo mobile app is gone. It was a thin wrapper that could not reach the device integration a phone deserves. Mobile is the responsive web UI over your private gateway with named device credentials — the same auth path native clients will use later.
The interactive chat REPL is gone from bazilion agent chat. One-shot mode (--message, --image, --file) and piped stdin remain, as do the chat management commands.

What this means for older homes

0.20.x upgrades in place, automatically, with the pre-migration snapshot.
0.19.x and earlier are refused cleanly and left untouched — those homes predate this contract. Keep the old home with its matching release for export, then reset it or point BAZILION_HOME at a new empty directory.
Existing token scopes, Teams, Agents and conversations are all preserved across the upgrade.

See the GitHub release for publication and validation details (the beta.1 release covers the schema-contract checkpoint, beta.2 the cross-platform hardening, beta.3 the failure-mode visibility audit, beta.4 the security gate and growth documentation). The 0.20.0 release notes remain available, and everything before 0.19.0 is summarised in previous changes.