> ## Documentation Index > Fetch the complete documentation index at: https://docs.slipway.sh/llms.txt > Use this file to discover all available pages before exploring further. # slipway.yaml field index > Every shipped field, one row each, with type and notes. Quick-scan table of every field slipway parses today. For the rationale and examples, see the [slipway.yaml overview](/slipway-yaml/overview) and adjacent pages. ## Top level | Path | Type | Required | Notes | | --------------------- | ------ | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | | `version` | int | yes | Currently `1`. | | `services` | map | yes | Keys: `^[a-z][a-z0-9-]{0,30}$`. | | `volumes` | map | no | Named volumes. Keys: `^[a-z][a-z0-9-]{0,30}$`. See [Named volumes](/slipway-yaml/volumes). | | `volumes..size` | string | no | Provisioned capacity, e.g. `10Gi`, `10GB`, `1Ti`, or bare `10` (GB). Omitted → plan default. Frozen at first provision (grow-only). Per-volume max 1024 GB; the org-wide total is capped by your plan. | ## `services.` | Path | Type | Required | Notes | | ----------------------- | ------ | ------------------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `build` | object | one of build/image | Build from repo. | | `image` | string | one of build/image | Use prebuilt image. | | `ports` | list | no | Empty / omitted → worker service. | | `env` | map | no | `${secret.*}`, `${var.*}`, `${service.*}` substitution. | | `enabled` | bool | no | Defaults to `true`. Set `false` to keep the service in the spec but not build/deploy it (an existing workload is torn down on the next deploy). | | `volumes` | list | no | Named-volume mounts, `":"`. The name must be declared in the top-level `volumes:`. A volume mounted by 2+ services is shared between them. | | `command` | list | no | Override the image's CMD. | | `args` | list | no | Override the image's args. | | `workdir` | string | no | Override the image's WORKDIR. Must be absolute. | | `depends_on` | list | no | Sibling services that must be ready before this one starts (Compose `service_healthy`). Same-spec only; self-refs, disabled refs, and cycles are rejected. See [depends\_on](/slipway-yaml/services#depends-on). | | `healthcheck.startup` | probe | no | See "Probes" below. | | `healthcheck.readiness` | probe | no | Gates cutover for public services. | | `healthcheck.liveness` | probe | no | Restarts unhealthy containers. | CPU and memory caps come from your plan — see [Plans & pricing](/organization/plans) — and aren't fields in `slipway.yaml`. A volume's `size:` *is* a field, but the total storage budget across all your volumes is plan-controlled. ## `services..build` | Path | Type | Required | Notes | | ------------ | ------ | -------- | ------------------------------------------------------------------------------------ | | `context` | string | yes | Relative to repo root. | | `dockerfile` | string | no | Defaults to `Dockerfile`. | | `args` | map | no | Build args. Values support `${secret.*}` / `${var.*}` / `${service.*}` substitution. | ## `services..ports[]` | Path | Type | Required | Notes | | -------- | ------ | -------- | --------------------------------------------------------------------------- | | `port` | int | yes | 1–65535. | | `public` | bool | no | Exposes the port publicly on the apps domain. | | `prefix` | string | no | Public hostname prefix. Defaults to service name. `^[a-z][a-z0-9-]{0,30}$`. | | `domain` | string | no | Verified custom parent zone. Must be claimed under **Settings → Domains**. | ## Probes A probe is `{ : {...}, }`. Exactly one handler. | Handler | Fields | | ------- | -------------------- | | `http` | `{ path, port }` | | `tcp` | `{ port }` | | `exec` | `{ command: [...] }` | | `grpc` | `{ port, service? }` | Timing fields (all optional, all Kubernetes-standard): `initialDelaySeconds`, `periodSeconds`, `timeoutSeconds`, `failureThreshold`, `successThreshold`. ## Substitution syntax | Form | Resolves to | | --------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `${secret.NAME}` | Secret. Env store first (when part of an environment), then org. | | `${secret.env.NAME}` | Secret. Environment store only — strict. Resolves only when this deployment is part of an environment. | | `${secret.org.NAME}` | Secret. Org store only — strict. | | `${var.NAME}` | Variable. Env → org fallback (same as bare `${secret.NAME}`). | | `${var.env.NAME}` | Variable. Environment store only — strict. | | `${var.org.NAME}` | Variable. Org store only — strict. | | `${service..}` | Sibling service URL/host/port/public\_url. `` is one of `url` / `host` / `port` / `public_url`. Resolves against any service in the same deployment — and, in an environment, any component's services. | | `${NAME}` | **Deprecated.** Alias for `${secret.NAME}`. Warns at deploy time. | Names for `${secret.*}` and `${var.*}` match `^[A-Z][A-Z0-9_]*$`. `${service.*}` uses lowercase service slugs. For `${service.*}`: use `url` for in-cluster sibling-to-sibling calls (bypasses the ingress and any preview auth); `public_url` is for external consumers (webhook callbacks, OAuth redirects). See [talking between services](/environments/overview#talking-between-services).