## Current state

Currently, `dev` and `staging` are deployed-to simultaneously by the deployment pipeline, then later to `prod`. The current intent is that `dev` can be pointed at an experimental branch, while `prod` and `staging` stay pointed at the trunk.

## How to update the pipeline

- E.g. to update the `dev` environment to use an experimental branch instead of the trunk, retrieve the pipeline:
  - `fly -t fr gp -p my-pipeline > pipeline.yml`
- Edit the pipeline file, for example with `vim`
  - `vim pipeline.yml`
- Unless the only change is to update which branch the pipeline is pointing to in `dev`:
  - Retrieve credentials file from s3
    - TODO: How?
  - Validate the change you are making against the pipeline code in git by rendering the pipeline against the credentials file
    - `fly validate`
- Push the altered pipeline
  - `fly -t fr sp -p my-pipeline -c pipeline.yml`

Note: Concourse also forces you to view and approve the changes after running `sp`

## Future changes

Current proposed changes would simplify the deployment pipeline to something like the following:

- Make changes on short-lived branch
- Push branch
- Open PR
- Review/respond until reviewers are satisfied
- Branch gets merged to trunk
- Trunk deploys to `dev`
- Smoke tests run
- Trunk gets promoted to `stage`
- Smoke + acceptance tests + (optional) manual testing
- Trunk goes to `production`