Where are images / containers built and run?

[greg-om]

This may seem like a weird question but for some reason I can run sam local invoke without docker desktop running on my machine.
Also, when I run sam build, docker desktop does have to be running.

Either way, I don't see any images from sam when I run docker images and don't see any containers running when I'm debugging locally when I run docker ps -a.

I feel like I'm missing something obvious but I can't figure out how this is working.

I'm on Ubuntu 24 and don't have any other container services installed / running as far as I know.

Here's the launch.json that I'm currently using:

{
"type": "aws-sam",
"request": "direct-invoke",
"aws": {
"credentials": "profile:us-dev",
"region": "us-west-2"
},
"invokeTarget": {
"target": "template",
"logicalId": "ShpToPqtFunction",
"templatePath": "template.yml"
},
"lambda": {
"runtime": "python3.12",
"environmentVariables": {
"API_HOST": "xxxxxxxxxx",
"OMT_ANALYTICS_SYNC_NAME": "xxxx"
},
"pathMappings": [
{
"localRoot": "${workspaceFolder}/shp-to-pqt-converter/app.py",
"remoteRoot": "/var/task/app.py"
},
{
"localRoot": "${workspaceFolder}/utils",
"remoteRoot": "/var/task/utils"
}
]
},
"sam": {
"containerBuild": true,
"localArguments": [
"-e",
"filepath/event.json"
],
"skipNewImageCheck": false
},
"name": "shp-debug"
}