ptweezy/cronstable

cronstable is a feature-rich job scheduler and simple workflow orchestrator for anything from a single machine to a cluster,
built with efficiency, security, and stability in mind. It runs your commands
on a schedule, defined in YAML or loaded from an existing crontab, and adds
retries, alerts, saved run history, workflows, and dashboards for the web, the
terminal, and iOS.
Why cronstable?
Scheduling
* **YAML and classic crontab files**: define jobs in YAML, or load an existing
crontab (see classic crontab files).
* **Business-day and hashed schedules**: run on the last weekday of the month
or the third Friday, and spread a fleet's jobs across the hour with H (see
schedules).
* **Second-level schedules and time zones**: run jobs as often as every
second, and evaluate each job's schedule in any time zone (see
second-level schedules and
time zones).
* **iCal calendar export**: subscribe to upcoming runs in your calendar app,
or view them in the dashboard's week calendar (see
calendar export).
* **Schedule introspection**: ask why a job did or didn't run at a given
moment, and get a field-by-field answer from the scheduler's own match test.
Collision heatmaps, duplicate detection, and slot suggestions help you place
new jobs (see schedule introspection).
* **Schedule linting**: catch schedules that can never run, uneven intervals,
and times that daylight saving time skips or repeats (see
schedule linting).
Failure handling
* **Retries with backoff**: retry failed runs with exponential backoff, and
choose whether a nonzero exit status or output on stderr or stdout counts as
a failure (see failure detection and retries).
* **Result verification**: check a job's output before recording success or
starting downstream tasks (see
result verification).
* **Alerts**: report failures through Sentry, email, Slack-compatible
webhooks, shell commands, and the Windows Event Log (see
reporting).
* **End-to-end encrypted push notifications**: send alerts to the
iOS app that only paired devices can decrypt (see
push notifications).
* **Late-run detection**: alert when a run is missing, late, or running too
long, and mark the job as overdue in the dashboards (see
late-run detection).
Durability and orchestration
* **Opt-in durable state**: keep run history and pending retries across
restarts, catch up missed runs, and give job commands shared storage, locks,
and idempotency keys (see
durable state).
* **Durable workflows**: run tasks as a directed acyclic graph (DAG) with
dependencies, data sharing, dynamic fan-out, sensors, and approval gates
(see workflow orchestration).
* **Selective workflow recovery**: retry failed tasks or replay failed dates
while reusing successful results (see
workflow recovery).
* **Shared resource pools**: limit capacity across jobs and workflow tasks,
with priority queues and deadlines (see
resource pools).
Observability and control
* **Web, terminal, and
iOS dashboards**: follow live logs, review history, control jobs
and workflows, and monitor the cluster.
* **HTTP API**: read job status and history, and start, cancel, or pause jobs
(see HTTP API).
* **Status badges**: show a job's live status in a README or wiki with an SVG
badge (see status badges).
* **Runtime pause and resume**: pause scheduled runs for maintenance without
editing configuration (see
pausing jobs).
* **Prometheus and statsd metrics**: track outcomes, durations, retries, and
cluster health (see metrics).
* **Per-job resource monitoring**: track CPU time and peak memory across each
job's process tree (see resource monitoring).
* **Built-in TLS**: serve the API over HTTPS, optionally require client
certificates, and rotate certificates without a restart (see
TLS and client certificates).
* **MCP server**: let AI agents inspect jobs and debug schedules, read-only by
default, with optional control (see
MCP).
Fleets
* **Opt-in clustering and leader election**: coordinate which replica runs
scheduled jobs through a Kubernetes Lease, an etcd lease, a shared
filesystem, or mutual TLS between peers (see
clustering and leader election).
* **Job-set ID**: compare configuration fingerprints to detect drift between
replicas (see job-set ID).
Deployment
* **Prebuilt releases**: container images in eight variants, and
self-contained binaries for Linux, macOS, Windows, FreeBSD, OpenBSD, NetBSD,
and illumos (see installation).
* **Built for restricted containers**: run as a non-root user with a read-only
root filesystem and restricted Kubernetes security settings (see
production container deployment).
* **Native Windows support**: run as a Windows service, install with WinGet or