## Summary
`stack emulator start` now resumes a fully-warm VM snapshot instead of
cold-booting, bringing startup from 30–120s down to ~5–8s with
per-install secret rotation, or ~2.5s with rotation opt-out. The
snapshot is captured **locally on first `stack emulator pull`**, not
shipped from CI — QEMU migration state isn't portable across
accelerators (KVM/HVF/TCG) or `-cpu max` feature sets, so a CI-captured
snapshot couldn't resume reliably on arbitrary user hardware.
Also bundles a pile of CLI QoL fixes (progress bars, PR/run artifact
pulls, PR-build download, native-TS ISO writer replacing
`hdiutil`/`mkisofs`/`genisoimage` host dep, unit tests).
| Scenario | Before | After |
|---|---|---|
| Cold boot (no snapshot) | 30–120s | same, works as fallback |
| `stack emulator pull` (one-time, includes local snapshot capture) |
~30s download | ~30s download + ~1–3 min cold-boot capture |
| Snapshot resume, normal start | — | **~5–8s** |
| Snapshot resume, `EMULATOR_NO_ROTATION=1` | — | **~2.5s** |
Backend (`/health?db=1`) and dashboard (`/handler/sign-in`) return 200
on all paths. Two successive snapshot resumes produce different rotated
PCK/SSK/SAK/CRON_SECRET values per install.
## How it works
**Build (CI)** — `docker/local-emulator/qemu/build-image.sh`:
1. Cloud-init provisioning runs to completion (migrations, seed,
slim-image) producing `stack-emulator-<arch>.qcow2`.
2. Image is built with a topology compatible with later snapshot capture
(pinned SMP=4, phantom seed/bundle ISOs, STACKCFG runtime ISO mounted at
build time, qemu-guest-agent running, placeholder hex secrets baked in
under `STACK_EMULATOR_BUILD_SNAPSHOT=1`).
3. CI publishes **only the qcow2** — no `.savevm.zst` ships.
**Pull (user's machine)** —
`packages/stack-cli/src/commands/emulator.ts` + `run-emulator.sh
capture`:
1. `stack emulator pull` downloads the qcow2 with a progress bar (or
from a PR / workflow run via `--pr` / `--run`).
2. CLI invokes `run-emulator.sh capture`: cold-boots the qcow2 with a
matching device layout (phantom ISOs, fsdev, pcie-root-port, virtfs
detached — migration-incompatible), waits for backend+dashboard health,
then drives QMP: `stop` → set `mapped-ram` + `multifd` caps → `migrate
file:state.raw` → poll `query-migrate` → `quit`. Raw mapped-ram file is
zstd-compressed to `stack-emulator-<arch>.savevm.zst` in the images dir.
3. `--skip-snapshot` opts out (first `start` will then cold-boot).
**Runtime** — `run-emulator.sh start`:
1. Launch QEMU with `-incoming defer` when a `.savevm.zst` is present;
decompress on first use, keep the `.raw` cached for subsequent starts.
2. QMP: same `mapped-ram` + `multifd` caps → `migrate-incoming
file:<.raw>` → poll for `paused` → `cont`.
3. Generate fresh per-install secrets on the host; pipe them
base64-encoded through QGA `guest-exec input-data` →
`trigger-fast-rotate` in the guest → `docker exec -e … rotate-secrets`.
4. `rotate-secrets` in the container: validate keys (hex-only), targeted
`sed` on the placeholder PCK across built JS, `UPDATE ApiKeySet`,
`supervisorctl restart stack-app cron-jobs` (with
`stopasgroup`/`killasgroup` so the Node children actually die and
release their ports).
5. Poll backend+dashboard health; if anything fails, clean up and fall
back to cold boot transparently.
**Security model**: placeholder hex values are baked into the snapshot
(`00…ff` PCK, `00…ee` SSK, `00…dd` SAK, `00…cc` CRON_SECRET). They are
non-secret by construction. Real per-install secrets are generated at
each `emulator start` and never leave the host.
## CLI changes (`packages/stack-cli`)
- **`src/lib/iso.ts`** (new): native TypeScript ISO 9660 + Joliet
writer, replacing the host-side `hdiutil`/`mkisofs`/`genisoimage`
dependency for generating the STACKCFG runtime config disk. Unit tests
in `src/lib/iso.test.ts`.
- **`src/commands/emulator.ts`**:
- `pull`: streamed downloads with progress bar + ETA; `--pr <number>`
and `--run <id>` to pull from a PR build's CI artifacts (uses
`extract-zip` for the nested zip); `--skip-snapshot` to opt out of the
one-time local capture.
- `start` (existing, extended): auto-pulls AND auto-captures when no
image exists, so first-ever `start` is self-bootstrapping; emits
`STACK_EMULATOR_CLI_WROTE_ISO=1` so the shell helper skips its own ISO
regen (avoids the genisoimage host dep).
- `capture` (new, invoked by `pull` and the auto-pull path of `start`):
drives the local snapshot capture via `run-emulator.sh`.
- `status`, `stop`, `reset`, `list-releases`: preflight +
path-resolution tightening (`STACK_EMULATOR_HOME` → images/run dirs).
- Unit tests in `src/commands/emulator.test.ts`.
- **`EMULATOR_NO_ROTATION=1`** env var skips the post-resume rotation
(intended for tests/CI where the placeholder secrets are fine — comes
with a loud warning).
## CI (`.github/workflows/qemu-emulator-build.yaml`)
- Builds **QEMU 10.2.2 from source** (cached), because
`mapped-ram`/`multifd` migration capabilities aren't available in the
distro's QEMU. Enables KVM on ubicloud runners so amd64 boots at
hardware speed.
- amd64 + arm64 both build on the same amd64 matrix
(`ubicloud-standard-8`); arm64 runs under cross-arch TCG (provisioning
only — boot/verify smoke test is amd64-only).
- Verification now runs through the CLI: `emulator start` → `emulator
status` → `emulator stop` against the freshly-built qcow2 (via
`STACK_EMULATOR_HOME` pointing at the workspace, so the CLI doesn't
silently auto-pull a prior release).
- Packages **only** the qcow2. No `.savevm.zst` upload / publish.
- Release notes updated.
## Key files
**Shell / guest:**
- `docker/local-emulator/qemu/build-image.sh` — snapshot-compatible
device topology + STACKCFG runtime ISO at build time
- `docker/local-emulator/qemu/run-emulator.sh` — `start`, `capture`,
`stop`, `reset`, `status`; `-incoming defer`, `.raw` cache, QGA-driven
rotation, cold-boot fallback
- `docker/local-emulator/qemu/common.sh` (new) — shared `qmp_session` +
`capture_vm_state` (factored out so build-image.sh and run-emulator.sh
share the capture path)
- `docker/local-emulator/qemu/cloud-init/emulator/user-data` —
placeholder secrets in snapshot mode, `wait-for-stack-ready`,
`trigger-fast-rotate`, qemu-guest-agent enabled
- `docker/local-emulator/rotate-secrets.sh` (new) — in-container
rotation (sed + UPDATE + supervisorctl)
- `docker/local-emulator/supervisord.conf` — `stopasgroup`/`killasgroup`
on `stack-app` and `cron-jobs`
- `docker/local-emulator/entrypoint.sh` — only mint CRON_SECRET if unset
(placeholder supplied in snapshot mode via --env-file)
- `docker/local-emulator/Dockerfile` — ships `rotate-secrets` to
`/usr/local/bin`
- `docker/server/entrypoint.sh` — source
`/run/stack-auth/rotated-secrets.env`; skip full-tree sentinel scan on
warm restarts via marker
**CLI:**
- `packages/stack-cli/src/lib/iso.ts` (new) + `iso.test.ts` (new)
- `packages/stack-cli/src/commands/emulator.ts` + `emulator.test.ts`
(new)
- `packages/stack-cli/vitest.config.ts` (new)
**CI:**
- `.github/workflows/qemu-emulator-build.yaml`
## Test plan
- [x] `docker/local-emulator/qemu/build-image.sh {amd64,arm64}` produces
`stack-emulator-<arch>.qcow2` with snapshot-compatible topology
- [x] `stack emulator pull` downloads qcow2 with progress, then captures
locally (~1–3 min) and writes `stack-emulator-<arch>.savevm.zst` in the
images dir
- [x] `stack emulator pull --skip-snapshot` stops after download
- [x] `stack emulator pull --pr <n>` / `--run <id>` pull from PR /
workflow run artifacts
- [x] `stack emulator start` on a fresh dir auto-pulls **and**
auto-captures, then starts; subsequent starts fast-resume in ~5–8s;
backend + dashboard return 200
- [x] `EMULATOR_NO_ROTATION=1 stack emulator start` completes in ~2.5s;
backend + dashboard return 200 with warning printed
- [x] Two consecutive `emulator start` invocations produce different PCK
values in the internal `ApiKeySet` row
- [x] `stack emulator status` / `stop` / `reset` resolve paths from
`STACK_EMULATOR_HOME`
- [x] Verified end-to-end on arm64 macOS under HVF (capture ~50s,
fast-resume ~6.5s)
- [x] `pnpm lint` and `pnpm typecheck` pass; stack-cli unit tests (iso +
emulator) pass
- [ ] CI green on this PR (qemu-emulator-build matrix, smoke test)
- [ ] `gh release download emulator-<branch>-latest` contains only
`stack-emulator-<arch>.qcow2` once this PR merges and publish runs
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
* **New Features**
* Snapshot fast-start/resume with optional warm-snapshot assets, runtime
ISO generation, and a cached QEMU build to speed emulator setup.
* CLI: streamed artifact downloads with progress, improved release/asset
handling, stronger preflight checks, and start/status/stop emulator
commands.
* Automated secret rotation and ability to apply rotated secrets at
container startup; supervisor control socket enabled.
* **Bug Fixes**
* More robust start/stop/resume flows with automatic fallback to cold
boot and improved process-group shutdown behavior.
* **Tests**
* New tests for CLI utilities and ISO image generation.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
|
||
|---|---|---|
| .agents/skills/pr-visual-writeup | ||
| .changeset | ||
| .claude | ||
| .cursor | ||
| .devcontainer | ||
| .github | ||
| .vscode | ||
| apps | ||
| claude | ||
| configs | ||
| docker | ||
| docs | ||
| docs-mintlify | ||
| examples | ||
| packages | ||
| patches | ||
| scripts | ||
| sdks | ||
| .dockerignore | ||
| .gitignore | ||
| .gitmodules | ||
| AGENTS.md | ||
| CHANGELOG.md | ||
| CLAUDE.md | ||
| CONTRIBUTING.md | ||
| LICENSE | ||
| package.json | ||
| pnpm-lock.yaml | ||
| pnpm-workspace.yaml | ||
| README.md | ||
| turbo.json | ||
| vitest.shared.ts | ||
| vitest.workspace.ts | ||
📘 Docs | ☁️ Hosted Version | ✨ Demo | 🎮 Discord
Stack Auth: The open-source auth platform
Stack Auth is a managed user authentication solution. It is developer-friendly and fully open-source (licensed under MIT and AGPL).
Stack Auth gets you started in just five minutes, after which you'll be ready to use all of its features as you grow your project. Our managed service is completely optional and you can export your user data and self-host, for free, at any time.
We support Next.js, React, and JavaScript frontends, along with any backend that can use our REST API. Check out our setup guide to get started.
Table of contents
- How is this different from X?
- ✨ Features
- 📦 Installation & Setup
- 🌱 Some community projects built with Stack Auth
- 🏗 Development & Contribution
- ❤ Contributors
How is this different from X?
Ask yourself about X:
- Is
Xopen-source? - Is
Xdeveloper-friendly, well-documented, and lets you get started in minutes? - Besides authentication, does
Xalso do authorization and user management (see feature list below)?
If you answered "no" to any of these questions, then that's how Stack Auth is different from X.
✨ Features
To get notified first when we add new features, please subscribe to our newsletter.
📦 Installation & Setup
To install Stack Auth in your Next.js project (for React, JavaScript, or other frameworks, see our complete documentation):
-
Run Stack Auth's installation wizard with the following command:
npx @stackframe/stack-cli@latest init -
Then, create an account on the Stack Auth dashboard, create a new project with an API key, and copy its environment variables into the .env.local file of your Next.js project:
NEXT_PUBLIC_STACK_PROJECT_ID=<your-project-id> NEXT_PUBLIC_STACK_PUBLISHABLE_CLIENT_KEY=<your-publishable-client-key> STACK_SECRET_SERVER_KEY=<your-secret-server-key> -
That's it! You can run your app with
npm run devand go to http://localhost:3000/handler/signup to see the sign-up page. You can also check out the account settings page at http://localhost:3000/handler/account-settings.
Check out the documentation for a more detailed guide.
🌱 Some community projects built with Stack Auth
Have your own? Happy to feature it if you create a PR or message us on Discord.
Templates
Examples
- Stack Auth Example by career-tokens
- Stack Auth Demo by the Stack Auth team
- Stack Auth E-Commerce Example by the Stack Auth team
🏗 Development & Contribution
This is for you if you want to contribute to the Stack Auth project or run the Stack Auth dashboard locally.
Important: Please read the contribution guidelines carefully and join our Discord if you'd like to help.
Requirements
- Node v20
- pnpm v9
- Docker
Setup
Note: 24GB+ of RAM is recommended for a smooth development experience.
In a new terminal:
pnpm install
# Build the packages and generate code. We only need to do this once, as `pnpm dev` will do this from now on
pnpm build:packages
pnpm codegen
# Start the dependencies (DB, Inbucket, etc.) as Docker containers, seeding the DB with the Prisma schema
# Make sure you have Docker (or OrbStack) installed and running
pnpm restart-deps
# Start the dev server
pnpm dev
# In a different terminal, run tests in watch mode
pnpm test # useful: --no-watch (disables watch mode) and --bail 1 (stops after the first failure)
You can now open the dev launchpad at http://localhost:8100. From there, you can navigate to the dashboard at http://localhost:8101, API on port 8102, demo on port 8103, docs on port 8104, Inbucket (e-mails) on port 8105, and Prisma Studio on port 8106. See the dev launchpad for a list of all running services.
Your IDE may show an error on all @stackframe/XYZ imports. To fix this, simply restart the TypeScript language server; for example, in VSCode you can open the command palette (Ctrl+Shift+P) and run Developer: Reload Window or TypeScript: Restart TS server.
Pre-populated .env files for the setup below are available and used by default in .env.development in each of the packages. However, if you're creating a production build (eg. with pnpm run build), you must supply the environment variables manually (see below).
Useful commands
# NOTE:
# Please see the dev launchpad (default: http://localhost:8100) for a list of all running services.
# Installation commands
pnpm install: Installs dependencies
# Types & linting commands
pnpm typecheck: Runs the TypeScript type checker. May require a build or dev server to run first.
pnpm lint: Runs the ESLint linter. Optionally, pass `--fix` to fix some of the linting errors. May require a build or dev server to run first.
# Build commands
pnpm build: Builds all projects, including apps, packages, examples, and docs. Also runs code-generation tasks. Before you can run this, you will have to copy all `.env.development` files in the folders to `.env.production.local` or set the environment variables manually.
pnpm build:packages: Builds all the npm packages.
pnpm codegen: Runs all the code-generation tasks, eg. Prisma client and OpenAPI docs generation.
# Development commands
pnpm dev: Runs the development servers of the main projects, excluding most examples. On the first run, requires the packages to be built and codegen to be run. After that, it will watch for file changes (including those in code-generation files). If you have to restart the development server for anything, that is a bug that you can report.
pnpm dev:full: Runs the development servers for all projects, including examples.
pnpm dev:basic: Runs the development servers only for the necessary services (backend and dashboard). Not recommended for most users, upgrade your machine instead.
# Environment commands
pnpm start-deps: Starts the Docker dependencies (DB, Inbucket, etc.) as Docker containers, and initializes them with the seed script & migrations. Note: The started dependencies will be visible on the dev launchpad (port 8100 by default).
pnpm stop-deps: Stops the Docker dependencies (DB, Inbucket, etc.) and deletes the data on them.
pnpm restart-deps: Stops and starts the dependencies.
# Database commands
pnpm db:migration-gen: Currently not used. Please generate Prisma migrations manually (or with AI).
pnpm db:reset: Resets the database to the initial state. Run automatically by `pnpm start-deps`.
pnpm db:init: Initializes the database with the seed script & migrations. Run automatically by `pnpm db:reset`.
pnpm db:seed: Re-seeds the database with the seed script. Run automatically by `pnpm db:init`.
pnpm db:migrate: Runs the migrations. Run automatically by `pnpm db:init`.
# Testing commands
pnpm test <file-filters>: Runs the tests. Pass `--bail 1` to make the test only run until the first failure. Pass `--no-watch` to run the tests once instead of in watch mode.
# Various commands
pnpm explain-query: Paste a SQL query to get an explanation of the query plan, helping you debug performance issues.
pnpm verify-data-integrity: Verify the integrity of the data in the database by running a bunch of integrity checks. This should never fail at any point in time (unless you messed with the DB manually).
Note: When working with AI, you should keep a terminal tab with the dev server open so the AI can run queries against it.














