| name | config-scaffolding |
| description | Scaffolds the config component for centralized configuration management, driven by component settings. |
| user-invocable | false |
Config Scaffolding Skill
Scaffolds the mandatory config component for centralized configuration management. Config sections are generated based on component settings from sdd/sdd-settings.yaml. Delegate to the techpack-settings skill for the authoritative config schema — it accepts a component type (config) and returns the settings object including referenced components and environment variable mappings.
When to Use
Use during project initialization to create the config component. The config component is mandatory — every SDD project has exactly one.
What It Creates
components/config/
├── package.json # Minimal package for workspace imports
├── tsconfig.json # TypeScript config for type exports
├── envs/
│ ├── default/
│ │ └── config.yaml # Base config (sections per component)
│ └── local/
│ └── config.yaml # Local overrides (empty)
├── schemas/
│ └── config.schema.json # Main schema (minimal)
└── types/
└── index.ts # Re-exports config types
Settings-Driven Config Generation
Config sections are generated based on component settings in sdd/sdd-settings.yaml:
Server Config Sections
API Server with database:
- name: main-server
type: server
settings:
server_type: api
databases: [primary-db]
provides_contracts: [public-api]
main-server:
port: 3000
probesPort: 9090
logLevel: info
databases:
primary-db:
host: localhost
port: 5432
name: myapp
ssl: false
Worker without database:
- name: background-worker
type: server
settings:
server_type: worker
databases: []
consumes_contracts: [public-api]
background-worker:
probesPort: 9090
logLevel: info
queue:
url: amqp://localhost:5672
apis:
public-api:
base_url: http://main-server:3000
Hybrid server (api + worker):
- name: main-server
type: server
settings:
server_type: hybrid
modes: [api, worker]
databases: [primary-db]
provides_contracts: [public-api]
main-server:
port: 3000
probesPort: 9090
logLevel: info
databases:
primary-db:
host: localhost
port: 5432
name: myapp
ssl: false
queue:
url: amqp://localhost:5672
Webapp Config Sections
- name: admin-dashboard
type: webapp
settings:
contracts: [public-api]
admin-dashboard:
apis:
public-api:
base_url: http://localhost:3000
Config Section Rules
| Setting | Config Impact |
|---|
server_type: api | Adds port: 3000 (business API) |
server_type: worker | Adds queue: { url: ... } |
server_type: cron | Adds schedule: {} placeholder |
provides_contracts: [...] | Adds port: 3000 (business API) |
consumes_contracts: [...] | Adds apis: { <name>: { base_url: ... } } per contract |
databases: [...] | Adds databases: { <name>: { host, port, name, ssl } } per database |
contracts: [...] (webapp) | Adds apis: { <name>: { base_url: ... } } per contract |
All Servers Get
probesPort: 9090 - Health check and metrics endpointlogLevel: info - Logging level
Config Component Purpose
The config component is a minimal TypeScript project with no runtime code. It exists so:
- Other components can import types via workspace package
@{project}/config/types
- YAML files are the source of truth for configuration values
- The system CLI (via
/sdd I want to generate config) generates merged configs for each environment
Environment Structure
Each environment has its own directory under envs/:
| Directory | Purpose |
|---|
envs/default/ | Base configuration - all environments inherit from this |
envs/local/ | Local development overrides (always present) |
envs/{env}/ | Other environments added as needed (staging, production, etc.) |
Merge order: envs/default/ → envs/{env}/
Template Variables
| Variable | Description |
|---|
{{PROJECT_NAME}} | Project name (lowercase, hyphens) |
Templates Location
All templates are colocated in this skill's templates/ directory:
skills/components/config/config-scaffolding/templates/
├── package.json
├── tsconfig.json
├── envs/
│ ├── default/
│ │ └── config.yaml
│ └── local/
│ └── config.yaml
├── schemas/
│ └── config.schema.json
└── types/
└── index.ts
Sync Behavior
When settings change (via /sdd with natural language about settings), the config component is automatically synced:
- New component added → Config section added with defaults
- Database added to server → Database subsection added
- Contract added to consumes_contracts → API subsection added
- Existing sections → Never modified or deleted (preserves user changes)
Scaffold Spec
The config component uses the engine for base template structure, but config section generation is dynamic (computed from component settings by the skill).
Base structure via engine
<plugin-root>/fullstack-typescript/system/system-run.sh scaffolding apply --spec spec.json
{
"target_dir": "<project-root>",
"base_dir": "<plugin-root>/skills",
"variables": { "PROJECT_NAME": "<project-name>" },
"operations": [
{
"type": "template_dir",
"source": "components/config/config-scaffolding/templates",
"dest": "components/config"
}
]
}
Dynamic config sections (skill computes content)
For each component, the skill computes the YAML config section content and writes it via write_file with if_exists: "skip" (additive only — never clobber existing sections). The skill builds the YAML content itself, then passes it to the engine.
{
"type": "write_file",
"path": "components/config/envs/default/config.yaml",
"content": "<computed-yaml-content>",
"if_exists": "overwrite"
}
Split: Use the engine for the component directory structure. Compute config sections yourself (from component settings) and write them via write_file.
Input
Schema: schemas/input.schema.json
Accepts the full list of project components whose settings drive dynamic config section generation.
Output
Schema: schemas/output.schema.json
Returns the scaffolding engine result: created files, directories, and scripts; skipped paths; errors; and a human-readable summary.
Related Skills
config-standards — Generated config files must follow these standards. Defines naming conventions, validation patterns, environment-specific overrides, and TypeScript type generation rules.
