Render Blueprints (render.yaml)

Blueprints define Render infrastructure as YAML (commonly render.yaml at the repo root). This skill focuses on authoring, wiring, projects/environments, previews, validation, and immutable fields. Heavy detail lives under references/.

When to Use

Apply this skill when the user:

• Creates or edits a render.yaml / Blueprint
• Wires databases, private services, or Key Value into app env vars
• Groups services with projects and environments
• Configures preview environments for pull requests
• Validates YAML against Render’s schema or CLI
• Asks what can or cannot change after a resource is created

For end-to-end deploy flows and MCP/CLI operations, see render-deploy. For env var strategy outside Blueprint syntax, see render-env-vars. For Docker-specific Blueprint fields, see render-docker.

Blueprint Structure

Top-level keys

Key	Purpose
services	Web, worker, cron, private service, Key Value, static (via web + runtime: static)
databases	Managed PostgreSQL instances
envVarGroups	Reusable env var sets attached to services
projects	Optional grouping; contains environments and service lists
previews	Defaults for PR preview environments

A Blueprint may also use patterns like ungrouped resources vs environment-scoped lists, depending on whether you adopt the projects model. Avoid duplicating the same logical resource in multiple places (see references/common-mistakes.md).

Schema and IDE validation

• JSON Schema URL: https://render.com/schema/render.yaml.json
• Configure your editor to associate render.yaml with that schema for completions and diagnostics.

Minimal example: web + PostgreSQL

databases:
  - name: mydb
    plan: basic-256mb
    region: oregon

services:
  - type: web
    name: api
    runtime: node
    region: oregon
    plan: starter
    buildCommand: npm ci && npm run build
    startCommand: npm start
    envVars:
      - key: DATABASE_URL
        fromDatabase:
          name: mydb
          property: connectionString

Service Types

type	Role
web	Public HTTP service (use runtime: static for static sites)
pserv	Private service (internal HTTP/TCP; not public)
worker	Long-running background process
cron	Scheduled job (schedule required)
keyvalue	Managed Key Value (Redis-compatible); alias redis accepted in Blueprints

Runtimes

Common runtime values: node, python, go, ruby, rust, elixir, docker, image, static.

• docker: Build from Dockerfile (see dockerfilePath, dockerContext, dockerCommand).
• image: Run a prebuilt container image (registry + optional registryCredential).
• static: Static site; requires staticPublishPath and build output paths (see references).

Cross-Service Wiring

Env vars under envVars (and analogous patterns in groups) can pull values from other resources instead of hardcoding secrets.

fromDatabase

Reference a database in databases: by name. Properties include:

• connectionString, host, port, user, password, database

fromService

Reference a service by name. Typical properties:

• host, port, hostport, connectionString, envVarKey

Which properties are valid depends on target service type (e.g. Key Value vs pserv). See references/wiring-patterns.md.

fromGroup

Attach shared vars from envVarGroups (by group name).

Other env var keys

• value: Literal string.
• generateValue: Let Render generate a random secret (password/API key).
• sync: Set sync: false for secrets that should not sync from repo on every update (see edge cases in wiring reference).

Full patterns and combinations: references/wiring-patterns.md.

Projects and Environments

For multi-service apps, use the projects/environments pattern instead of flat top-level services/databases. This groups all related resources into a single Render project, supports multiple environments (production, staging), and enables environment-scoped configuration.

projects:
  - name: my-app
    environments:
      - name: production
        services:
          - type: web
            name: api
            runtime: node
            plan: standard
            buildCommand: npm ci && npm run build
            startCommand: npm start
            envVars:
              - key: DATABASE_URL
                fromDatabase:
                  name: db
                  property: connectionString
              - key: REDIS_URL
                fromService:
                  type: keyvalue
                  name: cache
                  property: connectionString
              - key: API_SECRET
                sync: false

          - type: worker
            name: jobs
            runtime: node
            plan: starter
            buildCommand: npm ci
            startCommand: node worker.js
            envVars:
              - key: DATABASE_URL
                fromDatabase:
                  name: db
                  property: connectionString
              - key: REDIS_URL
                fromService:
                  type: keyvalue
                  name: cache
                  property: connectionString

          - type: keyvalue
            name: cache
            plan: starter
            maxmemoryPolicy: noeviction
            ipAllowList:
              - source: 0.0.0.0/0
                description: everywhere

        databases:
          - name: db
            plan: starter

Key rules:

• Each environment owns its services and databases lists.
• Do not define the same resource at both the root level and inside an environment.
• envVarGroups can be scoped to a project environment or shared across the workspace.
• Environment isolation (Professional+) can block cross-environment private network traffic.

For single-service apps, flat top-level services/databases is fine. Reach for the projects pattern when you have multiple services, need staging/production separation, or want environment-scoped env groups.

Preview Environments

Top-level previews controls PR previews:

• previews.generation: off (default), manual, or automatic
• previews.expireAfterDays: Auto-delete preview stacks after N days

Services can override preview behavior (e.g. service-level previews.generation). Limitations: autoscaling behavior, sync: false vars, previewPlan / flexible instance constraints—see references/preview-environments.md.

Validation

render blueprints validate

Requires Render CLI v2.7.0+. Run from the repo root (or pass the appropriate path options your CLI version supports). Fix schema and semantic errors before merging Blueprint changes.

Official schema: https://render.com/schema/render.yaml.json

Immutable Fields

CRITICAL: Some fields cannot change after the resource is created. Edits may be rejected or require replacement resources.

Services

• type: Cannot change (e.g. web → worker).
• runtime: Cannot change (e.g. node → docker).

Databases

Cannot change after creation:

• name (logical Blueprint/database identifier in this context)
• databaseName
• user
• region
• postgresMajorVersion

Plan other fields (disk, HA, replicas) carefully up front; consult Render docs for fields that can scale vs require recreation.

Key Fields (Quick Map)

Area	Fields
Plans	plan, previewPlan (previews), database plan
Build/run	buildCommand, startCommand, preDeployCommand, rootDir
Deploy	autoDeployTrigger: commit, checksPass, or off
Lifecycle	maxShutdownDelaySeconds: 1–300, default 30
HTTP	healthCheckPath, domains
Storage	disk (name, mountPath, sizeGB)
Scale	scaling / numInstances (see references)
Monorepo	buildFilter (paths, ignoredPaths)
Docker	dockerfilePath, dockerContext, dockerCommand, registryCredential

Deprecated names to avoid: env (use runtime), redis (use keyvalue), autoDeploy (use autoDeployTrigger), pullRequestPreviewsEnabled (use previews.generation). Details: references/common-mistakes.md.

References

Document	Contents
references/field-reference.md	YAML fields by service type, database, groups, projects, previews, scaling, disk, static, Key Value
references/wiring-patterns.md	fromDatabase / fromService / fromGroup examples, sync: false, generateValue, combinations
references/common-mistakes.md	Branch + previews, buildFilter, replicas, duplicates, preview plans, wiring mistakes
references/preview-environments.md	previews.generation, expiry, overrides, previewPlan, disks, PR workflow

Related Skills

• render-deploy — Deploy flows, Blueprint vs direct create, MCP/deeplinks
• render-env-vars — Env var strategy, secrets, Dashboard vs Blueprint
• render-docker — Dockerfile-backed services and image runtime nuances