Flavors Introduction

Flavors let you define environment-specific configuration variants without duplicating your entire configuration.

The Problem

Different environments need different settings:

Setting	Development	Staging	Production
NODE_ENV	development	staging	production
LOG_LEVEL	debug	info	warn
Docker target	development	development	production

Without flavors, you’d need separate config files for each environment.

The Solution: Flavors

Flavors define patches that modify your base configuration:

flavors:
  production:
    patches:
      - op: replace
        path: /env/NODE_ENV
        value: production

When you use --flavor production, EMB:

1. Loads your base configuration
2. Applies the flavor’s patches
3. Uses the modified configuration

Viewing Available Flavors

List defined flavors:

emb config print | grep -A 22 "^flavors:"

flavors:
  staging:
    patches:
      - op: replace
        path: /env/NODE_ENV
        value: staging
      - op: replace
        path: /env/LOG_LEVEL
        value: info
  production:
    patches:
      - op: replace
        path: /env/NODE_ENV
        value: production
      - op: replace
        path: /env/LOG_LEVEL
        value: warn
      - op: replace
        path: /defaults/docker/target
        value: production
      - op: add
        path: /defaults/docker/platform
        value: ${env:DOCKER_PLATFORM:-linux/amd64}

Base vs Flavored Configuration

Base Configuration

emb config print | grep -A 3 "^env:"

env:
  DOCKER_TAG: ${env:DOCKER_TAG:-latest}
  NODE_ENV: ${env:NODE_ENV:-development}
  LOG_LEVEL: ${env:LOG_LEVEL:-debug}

With Production Flavor

emb config print --flavor production | grep -A 3 "^env:"

env:
  DOCKER_TAG: ${env:DOCKER_TAG:-latest}
  NODE_ENV: production
  LOG_LEVEL: warn

Notice how NODE_ENV and LOG_LEVEL changed from templates to fixed production values!

When to Use Flavors

Flavors are ideal for:

• Environment differences - dev/staging/production settings
• Feature flags - enabling/disabling features per environment
• Resource sizing - different memory limits, replicas
• Docker targets - development vs production builds

Component-Level Flavors

Components can also define flavors in their Embfiles:

cat api/Embfile.yml | head -15

description: Production-ready API with multi-stage builds

resources:
  image:
    type: docker/image
    publish: true
    params:
      target: development

tasks:
  test:
    description: Run tests
    pre:
      - lint
    script: npm test

When both project and component define the same flavor, both sets of patches are applied (project first, then component).

Next Step

Continue to JSON Patch to learn about the patch operations in detail.