perplexes

Buildpacks

Heroku uses buildpacks to compile your application into a slug that is used across dynos for scaling horizontally quickly. A slug is a tar.gz archive of your app’s repository with certain pre-deploy features baked into the filesystem. Since everything to run your application is included in the archive, scaling becomes a simple matter of transferring it to a dyno, unpacking, and running the appropriate process. This is how Heroku achieves scaling-by-moving-a-slider.

For example, the Ruby buildpack will:

• install ruby locally
• install the jvm/jruby (if you’re using it)
• install/run bundler and install your gems to Rails.root/vendor
• create your database.yml (which ends up reading from your app’s environment variables)

adamwiggins

Make it real

Ideas are cheap. Make a prototype, sketch a CLI session, draw a wireframe. Discuss around concrete examples, not hand-waving abstractions. Don't say you did something, provide a URL that proves it.

Ship it

Nothing is real until it's being used by a real user. This doesn't mean you make a prototype in the morning and blog about it in the evening. It means you find one person you believe your product will help and try to get them to use it.

Do it with style

aaronpk

[aaron@parecki.com www]$ cat .htaccess 
RewriteEngine on
RewriteCond %{QUERY_STRING} resource=acct:(.+)
RewriteRule ^\.well-known/webfinger /profile/%1? [L]

[aaron@parecki.com www]$ cat profile/aaron@parecki.com
{
  "subject": "acct:aaron@parecki.com",
  "links": [
    {

smerrill

Socket activation:

NGINX=3:4

ListenStream=10646 (IPv6)
ListenStream=0.0.0.0:10646 (IPv4)
BindIPv6Only=ipv6-only

nginx.conf:
server {

julianlam

Provisioning and usage of unprivileged LXC containers via indirect login or script

As I've discovered, managing LXC containers is fairly straightforward, but when building out a system for provisioning out user maintained instances of NodeBB, it was imperative that unprivileged LXC containers were used, so that in the event of shell breakout from NodeBB followed by privilege escalation of the saas user, the root user in the LXC container would only be an unprivileged user on the host machine.

During the course of development, I ran into numerous blockers when it came to managing LXC containers in unexpected circumstances. Namely:

• Using LXC in a subshell is not directly supported. This usually happens under one of the following two circumstances:
  • After switching users via su or executing lxc-* commands as another user via sudo
  • Executing lxc-* commands via a program, application, or script. In my case, a Node.js application.

gtallen1187

"Scar Tissues Make Relationships Wear Out"

04/26/2103. From a lecture by Professor John Ousterhout at Stanford, class CS142.

This is my most touchy-feely thought for the weekend. Here’s the basic idea: It’s really hard to build relationships that last for a long time. If you haven’t discovered this, you will discover this sooner or later. And it's hard both for personal relationships and for business relationships. And to me, it's pretty amazing that two people can stay married for 25 years without killing each other.

[Laughter]

> But honestly, most professional relationships don't last anywhere near that long. The best bands always seem to break up after 2 or 3 years. And business partnerships fall apart, and there's all these problems in these relationships that just don't last. So, why is that? Well, in my view, it’s relationships don't fail because there some single catastrophic event to destroy them, although often there is a single catastrophic event around the the end of the relation

jayzz55

Building an SSH key management tool with Elixir

Sipping the Elixir

After being inspired by David's talk on Elixir at Hardhat, we decided to try and build our own SSH public key management tool, PubKeys, in Elixir. We're delighted to report back that Elixir is amazing.

Things we love about Elixir:

• Writing code in a functional style encourages us to break the code into small chunks of functions.
• Through the use of the function composition operator |>, the code is readable and elegant.
• Pattern matching is great.

jeffweiss

{:ok, connection} = AMQP.Connection.open
{:ok, channel} = AMQP.Channel.open(connection)
message = Enum.join(System.argv, " ") || "Hello World!"
AMQP.Exchange.declare(channel, "logs", :fanout)
AMQP.Basic.publish(channel, "logs", "", message)
IO.puts " [x] Sent '#{message}'"

imranismail

# Elixir :queue wrapper with modified behavior for empty queues to mimic Enumerable module in Elixir
defmodule Queue do
  def insert(queue, item), do: :queue.in(item, queue)

  def insert_last(queue, item), do: :queue.in_r(item, queue)

  def member?(queue, item), do: :queue.member(item, queue)

  def filter(queue, fun), do: :queue.filter(fun, queue)

jj1bdx

Originally from: http://erlang.org/pipermail/erlang-questions/2017-August/093170.html

For a safe and fast Erlang SSL server, there's a few 
configuration values you might want by default:

    [{ciphers, CipherList},      % see below
     {honor_cipher_order, true}, % pick the server-defined order of ciphers
     {secure_renegotiate, true}, % prevent renegotiation hijacks
     {client_renegotiation, false}, % prevent clients DoSing w/ renegs
     {versions, ['tlsv1.2', 'tlsv1.1']}, % add tlsv1 if you must