1Password is one of the best password managers available today. While the iOS, macOS, Windows, and Android clients are obviously the primary clients, they also have a command line tool.
You can automate the upload of files and other secrets to 1Password via the CLI. For instance, here's a script to zip up a directory and upload the contents:
#!/usr/bin/env bash
set -euxo pipefail
FILENAME=secrets.zip
DIR_TO_ZIP=mydir
zip -r $FILENAME $DIR_TO_ZIP
op create document $FILENAME --title="My Secrets File" --vault="Personal"
rm $FILENAME
You can then download the latest secrets file via the CLI with a little help from jq:
#!/usr/bin/env bash
set -euxo pipefail
FILENAME=secrets.zip
DOCUMENT_UUID=$(op list documents --vault="Personal" | jq -r 'sort_by(.updatedAt | fromdateiso8601) | map(select(.overview.title == "My Secrets File" and .trashed == "N")) | [ .[].uuid ] | last')
op get document $DOCUMENT_UUID > $FILENAME
unzip $FILENAME