Protocol Reference

All messages are UTF-8 JSON text frames unless noted as binary. Fields marked ? are optional.

---

Client → server messages

compile.start

Opens a compile session. Must be the first message sent on a new connection.

{
  "type": "compile.start",
  "api_key": "pk_live_...",
  "entry": "src/main.ts",
  "release": true,
  "target": "binary"
}

Field	Type	Description
api_key	string	Your Pure API key. See Authentication.
entry	string	Relative path within the tarball to the TypeScript or JavaScript entry point.
pre_command?	string	Shell command to run before compilation (e.g. pnpm install --frozen-lockfile). Runs inside the extracted tarball directory. If omitted, Pure auto-detects the right install command from your lockfile — see Default install command below.
release?	boolean	true for an optimized release build; false (default) for a debug build.
target?	"binary" | "node-addon"	Output format. "binary" (default) produces a standalone native executable. "node-addon" produces a Node.js native addon (.node) packaged as an installable npm tarball — see Node addon target below.
env?	object	Environment variables passed into the compile sandbox (key/value strings). Reserved keys like PATH, HOME, LD_PRELOAD, NODE_OPTIONS are rejected. Max 64 vars, 32 KB total, 4 KB per value.
sandbox_mem_gib?	number	Memory ceiling for the compile sandbox (GiB). Clamped to the platform maximum if exceeded.

Default install command

If you don’t supply pre_command, Pure inspects the root of your tarball and runs the right install command for the package manager whose lockfile is present:

Lockfile	Command
bun.lockb or bun.lock	bun install --frozen-lockfile (requires bun in your pre_command — Pure does not pre-install it)
pnpm-lock.yaml	pnpm install --frozen-lockfile
yarn.lock	yarn install --frozen-lockfile
package-lock.json	npm ci
package.json only	npm install
(none)	nothing — installation is skipped

Submit your own pre_command whenever you need a different command (e.g. enabling optional flags, installing bun, running a build step before Pure compiles, or pulling private deps with a token). Your custom pre_command has full outbound internet access, so curl | bash-style installers from any origin work.

Node addon target

When target is "node-addon", Pure produces a Node.js native addon instead of a standalone binary. The artifact returned via download_url is an npm tarball you install with:

npm install ./your-package-0.1.0.tgz

The package has the same name and version as the package.json at the root of your uploaded tarball, plus a .node file and a thin index.js shim that re-exports its surface. Your existing TypeScript types (*.d.ts) are preserved.

Use this when you want to ship a Pure-compiled module that other Node code can require() — without rewriting consumers around a separate binary.

Binary frames

After compile.start and before compile.upload.done, send the source tarball as one or more binary WebSocket frames. The server concatenates all frames in order.

The tarball must be a .tar.gz (gzipped tar archive) containing your project at the root level, not wrapped in an extra directory.

You may split the tarball across any number of frames. Typical usage is a single frame for small projects and multiple 64 KiB frames for larger ones.

compile.upload.done

Signals the end of the tarball upload.

{
  "type": "compile.upload.done",
  "total_bytes": 81920,
  "sha256": "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
}

Field	Type	Description
total_bytes	number	Total byte count of the uploaded tarball.
sha256	string	Lowercase hex SHA-256 of the complete tarball.

Sending compile.upload.done a second time on the same session is a no-op — the server ignores duplicate signals.

jobs.list

Request a list of recent jobs for an organization.

{
  "type": "jobs.list",
  "org_id": "org_abc123",
  "limit": 20
}

Field	Type	Description
org_id	string	Organization ID (visible in the dashboard under Settings).
limit?	number	Maximum jobs to return. Defaults to 20; maximum 100.

jobs.subscribe

Subscribe to real-time events for a specific job. If the job is already finished, the server replays stored events immediately.

{
  "type": "jobs.subscribe",
  "job_id": "job_xyz789"
}

---

Server → client messages

compile.queued

Sent when the job is accepted and placed in the compile queue.

{
  "type": "compile.queued",
  "job_id": "job_xyz789",
  "position": 2
}

Field	Type	Description
job_id	string	Unique identifier for this compile job. Use it for jobs.subscribe and jobs.list.
position	number	1-based position in the queue. Position 1 means the job is next to run.

compile.started

Sent when a worker picks up the job and begins processing it.

{
  "type": "compile.started",
  "job_id": "job_xyz789",
  "step": "compiling"
}

Field	Type	Description
job_id	string	Job identifier.
step	"pre_command" | "compiling"	"pre_command" if the worker is running the pre-compilation shell command; "compiling" when the actual compilation is underway.

compile.log

A line of compiler output. Emitted zero or more times during compilation.

{
  "type": "compile.log",
  "job_id": "job_xyz789",
  "line": "Compiling pure_hello v0.1.0",
  "ts": 1714000012345
}

Field	Type	Description
job_id	string	Job identifier.
line	string	One line of compiler output (no trailing newline).
ts	number	Unix timestamp in milliseconds when the line was emitted.

compile.done

Sent when compilation succeeds.

{
  "type": "compile.done",
  "job_id": "job_xyz789",
  "download_url": "https://...",
  "expires_at": 1714003600000,
  "work_units": 1280
}

Field	Type	Description
job_id	string	Job identifier.
download_url	string	Presigned URL to download the compiled binary.
expires_at	number	Unix timestamp (ms) when download_url expires.
work_units	number	Metered usage consumed by this job. See Billing.

compile.error

Sent when compilation fails or an error occurs during the session.

{
  "type": "compile.error",
  "job_id": "job_xyz789",
  "message": "human-readable description",
  "code": "JOB_FAILED"
}

Field	Type	Description
job_id?	string	Job identifier, if a job was created before the error.
message	string	Human-readable error description.
code?	string	Machine-readable error code. See Errors.

jobs.list.result

Response to a jobs.list request.

{
  "type": "jobs.list.result",
  "jobs": [
    {
      "id": "job_xyz789",
      "org_id": "org_abc123",
      "status": "succeeded",
      "entry": "src/main.ts",
      "created_at": 1714000000000,
      "finished_at": 1714000030000,
      "work_units": 1280
    }
  ]
}

Job status is one of: queued, running, succeeded, failed.

auth.error

Sent when authentication fails. The connection is closed immediately after.

{
  "type": "auth.error",
  "message": "key has been revoked",
  "code": "KEY_REVOKED"
}

See Authentication for all auth error codes.

---

Message ordering

Client                          Server
  │──── compile.start ──────────▶│
  │──── [binary frame(s)] ───────▶│
  │──── compile.upload.done ─────▶│
  │                               │◀── compile.queued
  │                               │◀── compile.started (step: pre_command)  [optional]
  │                               │◀── compile.started (step: compiling)
  │                               │◀── compile.log  [0..N]
  │                               │◀── compile.done  OR  compile.error
  │ (close or start new job)

The server may send compile.error at any point — including before compile.queued if the tarball is malformed or exceeds size limits.