I work on huge POS system project:
My main position is NodeJS Back-end developer, sometimes I cover UI(Angular 2+) features and bugs.
I create separate modules, add unit/integration tests(Jest, Mocha/Chai), take a part in deploy process(AWS), solve some deployment issues. I created a lot of integrations between another products and services. Every day I communicate with people from other teams and try to help each other to create the best product.