Looking into lerna now, how does SST know which stacks it needs to deploy and what changed? Not very clear to me.

Hey @Garret Harp it works on the service level. So each SST app (sst.json) and each SLS service (serverless.yml) is a service on SEED.

Ah ok so that means the lerna starter you guys have up on github would not do partial builds & deploys? (https://github.com/serverless-stack/lerna-yarn-starter). This only has the top level sst.json, I was under the impression this repo did partial builds/deploys which is why I was confused how it worked.

Yeah, if you just have 1 SST app in ur repo, SEED would always build & deploy it. But if you have 2 SST apps, and if both are yarn workspace packages, SEED can then use lerna to figure out who changed, and only build & deploy the changed one.

I believe our frontend always deploys I assume because the build slightly changes the file names or something like that not entirely sure not a frontend dev myself 😅 and the frontend is really what the issue is since it can be pretty slow.

The simplest way would be to export the url in the backend app:

this.addOutputs({
      ApiUrl: { value: api.url, exportName: "MyBackendUrl" },
    });

and then importing it in the frontend app:

Fn.importValue("MyBackendUrl")

And you’d make both SST apps yarn workspaces.