Foreword

Historically, the difference between scripting languages and real programming languages has been understood as the presence or absence of a compilation step. However, in recent decades the distinction has blurred; from time to time we have seen:

• Interpreters for languages that were originally meant to be compiled.
• Compilers for languages that were originally meant to be interpreted.
• Scripting engines internally compiling source code to bytecode before interpreting it.
• Real languages compiling to bytecode which is then mostly interpreted and rarely converted to machine code.

So, compiled vs. interpreted does not seem to be the real differentiating factor; nonetheless, we can usually tell a scripting language when we see one. So, what is it that we see?

My notes on Devoxx 2016 Belgium - Microservices Evolution: How to break your monolithic database by Edson Yanaga (I attended this conference)

Reduce maintenance window

Achieve zero downtime deployments

"Code is easy, state is hard"

Changes in a database schema from one version to another are called database migrations

Tools: Flyweight Liquibase

Migrations require back and forward compatibility

Baby steps = Smallest Possible Batch Size

Too many rows = Long Locks

My notes on Devoxx US 2017, Knowledge is Power: Getting out of trouble by understanding Git by Steve Smith

"If that doesn't fix it, git.txt contains the phone number of a friend of mine who understands git. Just wait through a few minutes of 'It's really pretty simple, just think of branches as...' and eventually you'll learn the commands that will fix everything."

My notes on GOTO 2016 - Microservices at Netflix Scale: Principles, Tradeoffs & Lessons Learned - R. Meshenberg

They have a division making a layer of tools for other teams to build their stuff on top of it.

Exceptions for statelessness are persistence (of course) but also caching.

Destructive testing - Chaos monkey -> simian army - in production, all the time. (During office hours)

Their separation of concerns looks like a grid, not like a vertical or horizontal table.

My notes on GOTO 2015 - Progress Toward an Engineering Discipline of Software - Mary Shaw

Notes

17:28 past the bridges and into software engineering

Software Engineering is all design. Production used to be printing the CDs, and nowadays it is hitting the "deploy" button.

"scaling the costs to the consequences" -- the point is not to minimize the cost, the point is to scale it to the consequences. Risks must be taken, and if the potential gains are huge, then the risks can be correspondingly large.

My notes on GOTO 2015 - DDD & Microservices: At Last, Some Boundaries! - Eric Evans

Microservices and Netflix - what is the connection?

Isolated data stores

"A service is something that can consume messages and can produce messages"