I haven't had cause to drop one of these since November last year, probably at least in part because Edge seems to have a nasty habit of eating tabs! In no particular order, and likely of more use to me, than to you....
The MT940 format is one used by banks (via SWIFT) for sending electronic bank statements to customers. So, if you want to import bank statement data into your system it'll probably be MT940 files that you'll end up processing. The really nice thing about them is that the format seems to be standard, but then each bank customises the hell out of it. So, by all means look at some of the NuGet packages available for processing MT940 files but don't be under any illusion that they'll work unless they're for your banks dialect of MT940!
This post by Stephen Cleary from 2012 (six years ago, eep!) is one that every developer who's gone within a mile of async/await code should read and understand. The short version is, if your code's async, make sure it's all async. C# 7.1 implemented support for async Main methods in August last year so that last hold out has disappeared too.
The write-up by dbc of ways to mitigate against heavy memory usage when serializing large amounts of data with Json.NET is awesome. The principles are generalisable as well, so even if you've never used Json.NET and never intend to, it's probably worth a read.
Reminder to self: When working with ancient asp.net web app and trying to convert it to use IIS Express, a 401.2 error means that the app needs to be configured to use Windows auth
Sometimes you find a SQL Server that you've inherited where the 'sa' password isn't known and there aren't any Windows accounts that have 'sa' level access to the server. It's a bit of a faff but you can recover access - faff is defintiely better than having to re-install SQL Server!