You should not establish Elasticache as the Redis deployment solution. The Redis company tries hard to explain their value, using their Cloud may be a better solution. redis.io/blog/signs-y...

Very good summary for people that are familiar with high availability deployments.

Some friends call me that: Jéjé.

Do you put the ? at the end of the condition line, or at the beginning of the 1st statement line?

Excellent !

They don't want to admit they are hosted on AWS to stay respectable in their domain?

Very well explained. I've never had to run a down migration. In fact, I always make sure that I have a version of the code that is compatible with the 2 states of the database. This is essential for zero-downtime deployment.

Congratulations!

You'll beat all your PR with this beautiful machine.

How does it works?

That's an impressive compression algorithm, going from 552KB PNG to an int of 64 bits. You get an unbeatable compression ratio of 99.9985%.

The # gives a very high number. Do you store all the generated images somewhere?

This is the state of the art for storing dates in a database, UTC should be the default way of saving date times.
And sometimes the original timezones need to be stored along with the date. Use a second field for the TZ.