This is going to be purposefully vague because 1) a lot of obvious reasons and 2) we aren't a monolithic engineering organization and practices vary a lot between teams and departments. This is all stuff you could largely glean from a little sleuthing.
That being said:
- The overwhelming majority of our infrastructure is run in our own data centers. It's very different from working with cloud-based infra.
- I work on Archive-It, which is an earned income service best summed up as a SaaS version of Wayback Machine. I'm the team lead and wear a lot of different hats: I handle a lot of the traditional full-stack web development, but I also spend a lot of time working on crawling, processing pipelines, databases, and operations.
- Archive-It is built on a lot of open-source projects that Archive either leads or makes significant contributions to, most notably two web crawler projects: Heritrix and Brozzler.
- My team's web stack is pretty standard: We use Django and Flask for a lot of our web backend, but there's some other stuff mixed in there. It's a hodgepodge of frontend, but we like TypeScript + Web Components + Lit.
- My team currently deploys with Ansible straight to VMs. Some other teams are using different tooling and more containerization, but we really only use containers for local dev environments.