Daniel Díaz Carrete danidiaz

A curated list of AWS resources to prepare for the AWS Certifications

A curated list of awesome AWS resources you need to prepare for the all 5 AWS Certifications. This gist will include: open source repos, blogs & blogposts, ebooks, PDF, whitepapers, video courses, free lecture, slides, sample test and many other resources.

Löb with error handling

löb is a well-known function in Haskell for implementing spreadsheet-like behaviors and tying the knot. It is defined as:

loeb :: Functor f => f (f a -> a) -> f a
loeb fs = xs
  where xs = fmap ($ xs) fs

Don't use VPN services.

No, seriously, don't. You're probably reading this because you've asked what VPN service to use, and this is the answer.

Note: The content in this post does not apply to using VPN for their intended purpose; that is, as a virtual private (internal) network. It only applies to using it as a glorified proxy, which is what every third-party "VPN provider" does.

A Russian translation of this article can be found here, contributed by Timur Demin.
A Turkish translation can be found here, contributed by agyild.
There's also this article about VPN services, which is honestly better written (and has more cat pictures!) than my article.

Introductory Material

Add Graal JIT Compilation to Your JVM Language in 5 Steps, A Tutorial http://stefan-marr.de/2015/11/add-graal-jit-compilation-to-your-jvm-language-in-5-easy-steps-step-1/
The SimpleLanguage, an example of using Truffle with great JavaDocs. It is the officle getting-started project: https://github.com/graalvm/simplelanguage
Truffle Tutorial, Christan Wimmer, PLDI 2016, 3h recording https://youtu.be/FJY96_6Y3a4 Slides

HTTP Streaming (or Chunked vs Store & Forward)

The standard way of understanding the HTTP protocol is via the request reply pattern. Each HTTP transaction consists of a finitely bounded HTTP request and a finitely bounded HTTP response.

However it's also possible for both parts of an HTTP 1.1 transaction to stream their possibly infinitely bounded data. The advantages is that the sender can send data that is beyond the sender's memory limit, and the receiver can act on

	#!/usr/bin/env stack
	> -- stack --resolver lts-6 --install-ghc runghc --package classy-prelude --package lens --package wreq

	Blah Blah words about this single file executable README goes here.

	> {-# LANGUAGE DeriveAnyClass #-}
	> {-# LANGUAGE DeriveGeneric #-}
	> {-# LANGUAGE NoImplicitPrelude #-}
	> {-# LANGUAGE OverloadedStrings #-}

	{-# LANGUAGE CPP #-}
	{-# LANGUAGE ScopedTypeVariables #-}
	{-# LANGUAGE FlexibleInstances, FlexibleContexts #-}
	{-# LANGUAGE DataKinds, GADTs, KindSignatures, TypeOperators, UndecidableInstances #-}

	#if __GLASGOW_HASKELL__ < 708
	#error "requires GHC 7.10 or newer"
	#endif
	module Main (main) where

	{-# language DataKinds, PolyKinds, ScopedTypeVariables, UndecidableInstances,
	FlexibleInstances, FlexibleContexts, GADTs, TypeFamilies, RankNTypes,
	LambdaCase, TypeOperators, ConstraintKinds #-}

	import GHC.TypeLits
	import Data.Proxy
	import Data.Singletons.Prelude
	import Data.Singletons.Decide
	import Data.Constraint

	{-
	This code shows how to check if a type-level list contains a given type.
	It first shows the approach required for older versions of GHC (< 7.6.x)
	and then a version using closed type families supported in GHC 7.8.1 and greater.
	-}

	{-# LANGUAGE FlexibleContexts #-}
	{-# LANGUAGE UndecidableInstances #-}
	{-# LANGUAGE FlexibleInstances #-}
	{-# LANGUAGE MultiParamTypeClasses #-}

	{-# LANGUAGE OverloadedStrings #-}
	module Network.HttpSSL (
	postSSL
	, SSLOptions (..)
	) where

	{-
	build-depends:
	wreq
	, HsOpenSSL