I use Microsoft IIS because it is shipped by default with Windows Servers for which of them I usually develop applications. IIS perfectly managed from PowerShell which I use as well, thus it is very easy choice for me. I could have clean Windows instance and bring it to desired state using PowerShell capabilities. Also this is default configuration for debugging in Visual Studio which means that I develop in the environment which is closer to production.
I use Slack because it offers the best experience, even on the free tier (which we're still using). As a comparison, I have had in depth experience with HipChat, Stride, Skype, Google Chat (the new service), Google Hangouts (the old service). For self hosted, Mattermost is open source and claims to support most Slack integrations, but I have not extensively investigated this claim.
We are highly dependent on G Suite for all our collaboration and productivity needs, from Gmail and Calendar to Sheets and Docs. While it may not be as robust as Microsoft's offerings in those areas, it's totally cloud-based, we've never had any downtime issues and it integrates well with our other tools like Slack. We write and collaborate on all our specs/PRDs in Docs, share analyses via Sheets and handle our meetings via Calendar. #StackDecisionsLaunch #ProductivitySuite #Collaboration #DocumentCollaboration
We recently implemented GraphQL because we needed to build dynamic reports based on the user preference and configuration, this was extremely complicated with our actual RESTful API, the code started to get harder to maintain but switching to GraphQL helped us to to build beautiful reports for our clients that truly help them make data-driven decisions.
Our goal is to implemented GraphQL in the whole platform eventually, we are using Graphene , a python library for Django .