Jérôme Parent-Lévesque jeromepl

How to setup a practically free CDN using Backblaze B2 and Cloudflare

⚠️ Note 2023-01-21
Some things have changed since I originally wrote this in 2016. I have updated a few minor details, and the advice is still broadly the same, but there are some new Cloudflare features you can (and should) take advantage of. In particular, pay attention to Trevor Stevens' comment here from 22 January 2022, and Matt Stenson's useful caching advice. In addition, Backblaze, with whom Cloudflare are a Bandwidth Alliance partner, have published their own guide detailing how to use Cloudflare's Web Workers to cache content from B2 private buckets. That is worth reading,

This project is a tiny compiler for a very simple language consisting of boolean expression.

The language has two constants: 1 for true and 0 for false, and 4 logic gates: ! (not), & (and), | (or), and ^ (xor).

It can also use parentheses to manage priorities.

Here is its grammar in BNF format:

expr ::= "0" | "1"

Docker for Mac

On M1 machines, Docker for Mac is running a lightweight linux ARM VM, then running containers within that, so containers are essentially running natively. Don't be fooled by the fact the UI or binary CLI tools (e.g. docker) might require Rosetta.

Within that VM is an emulation layer called QEmu. This can be used by docker to run Intel containers. This does not use Rosetta at all, and has a roughly 5-6X performance penalty. (If you just upgraded your CPU this may result in a similar performance to your old machine!)

Pulling and running with Docker

Many images in public registries are multi-architecture. For instance at the time of writing on Docker Hub the php:8.0-cli image has the following digests:

	The question was asked why I (as a programmer who prefers dynamic languages) don't consider static types "worth it". Here
	is a short list of what I would need from a type system for it to be truely useful to me:

	1) Full type inference. I would really prefer to be able to write:

	(defn concat-names [person]
	(assoc person :full-name (str (:first-name person)
	(:second-name person))))

	And have the compiler know that whatever type required and produced from this function was acceptible as long as the