plus/minus epsilon

Disruptive innovation requires the creation of a new disruptive technology. So if Wikipedia is an example of disruptive innovation, what technology did they create? Like most people, I hear “new technology” and my mind naturally starts looking for machinery and gears combining to accomplish something that nobody thought was possible before. But that’s not here: Wikipedia is widely considered technically unremarkable. Instead, what stands out to me about Wikipedia and makes me think “that shouldn’t work” is anonymous contribution.

Alternate Title: Cloudflare’s Plan for World Domination (Not Really (Maybe))

Cloudflare’s browser product will mark the beginning of a two-sided network. That is, we’ll have answers to the two following questions:

Why do I feel like it’s easier to write on Tumblr than on any kind of self-hosted blog?

• Tumblr has no friction between deciding to write something and starting to write.
• It has a WYSIWYG editor that’s fun to use.
• I can queue posts for later.
• It’s social. There’s the possibility of my content getting seen and interacted with by other people.
• In turn, I could find other people that I like and follow them and see their posts on here.

What do people like about their jobs (besides money)?

1. Social interaction: A sense of community
2. Autonomy: An ability to decide how they work
3. Variety: A defense against boredom
4. Feedback: Knowing if they’ve done a good job
5. Sense of contribution: An understanding of how their effort helps the company achieve its mission

Wikipedia is a classic, underrated example of disruptive innovation. They started out by serving the low-end market of people that want information immediately, for free, and are fine with that information not necessarily being high quality. This was previously a market that print encyclopedias like Britannica served with door-to-door salespeople, but while trying to grow their revenue they naturally pursued higher-margin opportunities with universities and academic researchers.

Surprisingly often, well-managed companies fail to compete against startups that pursue their customer base. By not competing, these large companies lose market share and often go out of business, even though they have substantially more resources than their startup competition.

Recently, a project I was working on required a cache that would ideally be capable of storing tens of millions of entries, reaching into the multiple-terabyte range. At this scale, using a single spinning disk is significantly cheaper than storing everything in memory, which Redis or Memcached would require. Another classic KV store, LevelDB, also ends up being impractical because it writes the value for each key to disk multiple times. If your values are small, LevelDB can be really really performant, but in my case the values are moderately sized (tens of kilobytes) and writing them to disk multiple times quickly becomes user-visible. And finally, I expected that storing this many entries on-disk as individual files in a folder would cause issues with inode exhaustion, and ultimately, the ACID guarantees that a filesystem provides have never been super clear to me.

Certificate Transparency (CT) is a relatively new addition to the TLS ecosystem. Its fundamental goal is to provide the tools for website operators to detect the mis-issuance of certificates for their own websites. Historically, this is something that only large tech companies have been able to do successfully.

In Adi Shamir's paper titled How to Share a Secret, he quotes this problem from a combinatorics textbook:

Eleven scientists are working on a secret project. They wish to lock up the documents in a cabinet so that the cabinet can be opened if and only if six or more of the scientists are present. What is the smallest number of locks needed? What is the smallest number of keys to the locks each scientist must carry?