Using env vars
ZombieNet can also make replacements in the network config using env variables. To define a replacement you need to use the {{ENV_VAR_NAME}} syntax.
For example, from the previous example but using env variables could be:
[relaychain]
default_image = "{{ZOMBIENET_INTEGRATION_TEST_IMAGE}}"
chain = "rococo-local"
  [[relaychain.nodes]]
  name = "alice"
  [[relaychain.nodes]]
  name = "bob"
[[parachains]]
id = 100
add_to_genesis = false
  [parachains.collator]
  name = "collator01"
  image = "{{COL_IMAGE}}"
  command = "adder-collator"
Then you can export the needed values before run the command to spawn the network again:
export ZOMBIENET_INTEGRATION_TEST_IMAGE=docker.io/paritypr/polkadot-debug:master
export COL_IMAGE=docker.io/paritypr/colander:4131-ccd09bbf
./zombienet-macos spawn examples/0001-small-network.toml