Do not let your CDN betray you: Use Subresource Integrity

Mozilla Firefox Developer Edition 43 and other modern browsers help websites to control third-party JavaScript loads and prevent unexpected or malicious modifications. Using a new specification called Subresource Integrity, a website can include JavaScript that will stop working if it has been modified. With this technology, developers can benefit from the performance gains of using Content Delivery Networks (CDNs) without having to fear that a third-party compromise can harm their website.

<script src="https://code.jquery.com/jquery-2.1.4.min.js"
integrity="sha384-R4/ztc4ZlRqWjqIuvf6RX5yb/v90qNGx6fS48N0tRxiGkqveZETq72KgDVJCp2TC"
crossorigin="anonymous"></script>

Scaling your API with rate limiters

Concurrent requests limiter

Instead of “You can use our API 1000 times a second”, this rate limiter says “You can only have 20 API requests in progress at the same time”.

.. Fleet usage load shedder

We always reserve a fraction of our infrastructure for critical requests. If our reservation number is 20%, then any non-critical request over their 80% allocation would be rejected with status code 503.

Grumpy: Go running Python!

Google runs millions of lines of Python code. The front-end server that drives youtube.com and YouTube’s APIs is primarily written in Python, and it serves millions of requests per second! YouTube’s front-end runs on CPython 2.7,

.. but we always run up against the same issue: it’s very difficult to make concurrent workloads perform well on CPython.

.. Grumpy is an experimental Python runtime for Go. It translates Python code into Go programs, and those transpiled programs run seamlessly within the Go runtime.

.. The goal is for Grumpy to be a drop-in replacement runtime for any pure-Python project.

.. In particular, Grumpy has no global interpreter lock, and it leverages Go’s garbage collection for object lifetime management instead of counting references. We think Grumpy has the potential to scale more gracefully than CPython for many real world workloads.

.. Grumpy programs can import Go packages just like Python modules! For example, the Python snippet below uses Go’s standard net/http package to start a simple server