For the sake of general interest, here is my response to a question we received about the financial viability of our javascript CDN service.
The financial obligations of running a service like this is something we are keenly aware of.
As grimen said, we are only hosting static files. To further reduce costs we serve minified, gzipped files. In fact, most of the files we host at the moment are under 4kb (after compression).
Let’s run some quick numbers:
(NB: I am using numbers slightly higher than the prices listed by Amazon for the Cloudfront service to account for unforseen expenses. Also, this is a rough calculation)
Transfer Costs / month: 10,000,000 * 0.00001 = 100(GB) * $0.20 = $20
Request Costs / month: (10,000,000 / 10,000) * $0.01 = $10
Total Cost / month for 10,000,000 requests and script downloads: $30
NB: I have ignored the case where a user accesses cdnjs with a primed cached (e.g. they have already downloaded the script and their browser has cached it). Amazon Cloudfront will return a 304 Not Modified HTTP status code, meaning the browser will use its cached copy of the script. This means that in practice, the transfer costs will actually be lower than the number of requests would indicate.
So we can see that even for a not-insignificant number of requests, the costs of hosting the files are actually quite reasonable.
Food for thought.
What follows is a bullet point summary of what I thought were the most important parts of this book:
If you’re interested in startups and you haven’t heard of “The Four Steps to the Epiphany” by Steve Blank, you’re probably not very interested in books. I would describe it as a process to help steer a startup through the chaotic path to profitability and success. “The Four Steps” reads a lot like a university textbook, leaving some recent Customer Development converts in search of a more readable summary.
This is where The Entrepreneur’s Guide to Customer Development comes in. The most important thing to note about this book is that it focuses entirely on the first phase of Customer Development: Customer Discovery. This isn’t a bad thing, it’s just worth noting.
I felt that that the aim of this book was to provide a gentler introduction to Customer Discovery. A good analogy for this book would be CliffsNotes for Customer Development. At a slim 74 pages or so, it gives you a set of actionable items that you can implement immediately, and presents this information in a much more conversational tone. I found it a much easier read than the Customer Discovery chapter in “The Four Steps”.
