Spin up a development version

Let's switch to the dev channel as we want the bleeding edge build from DHIS2 v40. We want it seeded with a v40 dump so we are going to run it with --seed.

d2 cluster up 2.40 --channel dev --seed

# result
# ---
# channel: dev
# dhis2Version: 2.40
# dbVersion: 2.40

Since the 2.40 branch exists in dhis2-core and the 2.40 dump exists on the database site the tool doesn't need more information to create an environment.

Now, let's run a master build from the dev channel:

d2 cluster up master \
    --channel dev \
    --db-version dev \
    --seed

# result
# ---
# channel: dev
# dhis2Version: master
# dbVersion: dev

Since the --dhis2-version argument was omitted, it used the {name} as fallback. Since we used master as the name, and the master tag exists in the dhis2/core-dev it is able to resolve a complete environment.

We could also have run:

d2 cluster up master \
    --channel dev \
    --db-version dev \
    --dhis2-version master \
    --seed

The name can be anything you wish, but remember to specify channel, dhis2-version, and db-version in that case.