Activitypub addresses the problem of participating in a decentralized social network with a low barrier to entry. You participate through the server you have joined but often times the people you want to interact with reside on other servers. For instance, if you want to follow a friend, visiting that friend’s url does not provide a simple follow button. That simple follow button is on your own server but you need to navigate to your server’s profile page for your friend who is on a remote server. An easy way to do this is to perform a search on your friend’s webfinger address which looks like an email address. Your server can make a forward discovery request to ask for the url of your friend’s actor document so that you can visit your server’s profile page for your friend.

Your server needs to do more than forward discovery to validate that the actor url actually belongs to the requested webfinger address in case the domain of the webfinger address is different than the domain of the actor url. In this case, after fetching the actor url, your server needs to construct a 2nd webfinger address composed of the preferredUsername it found in the actor document followed by the domain of the actor url. Your server can make a webfinger request to this 2nd address and use the response to verify that the subject matches the original webfinger address that you submitted in your search. If they don’t match, your server can display the profile associated with the 2nd address and ignore the original webfinger address since the validation failed.

I wrote a should use the custom domain example spec to make sure the server can accommodate a custom domain different than the domain in the actor url.

In the example spec, we are given bob@example.com whose webfinger points to an actor document at activitypub.test:

let(:bob_webfinger_info) { {"subject" => "acct:bob@example.com", "links"=>[{"rel"=>"self", "type"=>"application/activity+json", "href"=>"https://activitypub.test/users/bob" }]} }

It is not enough to fetch the actor document and assume bob is at activitypub.test. Instead, as Mastodon does, a reverse discovery should be performed by constructing a new WebFinger address by combining the preferredUsername from the actor document and the hostname of the id of the actor document.

In the example spec, this new WebFinger address would be bob@activitypub.test and, in this case, the test host activitypub.test returns a webfinger response that confirms that the subject is bob@example.com that was requested with forward discovery.

Another example spec should not use the custom domain if subject returned by activitypub server is different than the original subject tests when george@example.com is not recognized by the host activitypub.test who george points his webfinger address to:

let(:george_webfinger_info) { {"subject" => "acct:george@example.com", "links"=>[{"rel"=>"self", "type"=>"application/activity+json", "href"=>"https://activitypub.test/users/george" }]} }

In this case, the validation fails because the host returns acct:george@activitypub.test in the 2nd webfinger request instead of acct:george@example.com so example.com is discarded and the domain of the account should fall back to activitypub.test.

Bitcoin failed. J.P. Koning notes in The end of El Salvador’s bitcoin payments experiment:

But here was a government that was going to champion the stuff, nullifying all of the headwinds against bitcoin in one stroke! The government meddling hypothesis would be put to test.

The Salvadoran government used a combination of sticks and carrots to kick-start adoption. First, let's list the carrots. The capital gains tax on bitcoin was set to zero to remove the hassle of buying stuff with bitcoin. The government also built a bitcoin payments app, Chivo, for all El Salvadoreans to use. (Chivo also supports U.S. dollar payments.) Anyone who downloaded Chivo and transacted with bitcoin would receive a $30 bitcoin bonus—that's a lot of money in El Salvador. Gas stations offered $0.20 off of a gallon of gas for customers who paid with the app. People could also use Chivo to pay their taxes with bitcoin.

The biggest carrot was zero-transaction fees. Any payment conducted with Chivo was free, as was converting bitcoins held in the Chivo app into U.S. dollars and withdrawing cash at Chivo ATMs. These Chivo ATMs were rolled out across El Salvador and in the U.S., too, to encourage the nascent U.S.-to-El Salvador bitcoin remittance route. Bitcoin ATMs are usually incredibly pricey to use, but in El Salvador the government would eat all the transaction fees. What a fantastic deal.

As for the stick, Bukele introduced a forced-tender rule. Beginning in 2021, businesses were required to accept the orange coin or be punished. This was costly for them to comply with. They would have to update point of sale software, signage, train employees, and set up new processes for handling bitcoins post-sale.

By all rights, this combination of sticks and carrots should have led to a flourishing of bitcoin payments. But it didn't.

Koning concludes:

The saddest thing about El Salvador's bitcoin experiment is that all sorts of time and resources have been wasted. El Salvador is not a rich country. The money spent on building and operating Chivo, compliance by businesses, bitcoin signage, and subsidies could have been better deployed on more important things like health and education.  One hopes that other countries learn from this experience and avoid going down the same route that El Salvador did.

Deadly D.C. Plane Crash Comes Months After Congress Ignored Warning About Traffic at Reagan Airport

As the new administration is playing stupid games, yesterday morning, prior to yesterday’s aviation disaster, professor Thomas Schaller cautioned:

An FAA employee I know confirms agency already lacks sufficient air traffic controllers. The so-called “buyouts” and other attacks on federal employees won’t help. Remember that fact when the flight delays (crashes?) commence and Trumpers start falsely blaming DEI or Biden.

This should be a wakeup call and I have a deeper appreciation for people like Phyllis Fong who this week have resisted the illegal orders that are already causing significant harm. On the other hand, if you like anarchy and disaster, congratulations.

As I just registered for a new season of beer league hockey starting this weekend, I thought about an episode of C’est comme ça que je t’aime I recently watched which is set in 1974 Sainte-Foy, Quebec City. Nearly all the 1974 Quebec cultural references are new to me and in this episode, there is an adventure in a hockey arena and you can pause the video in a few places and see signage in the background for a junior hockey team called Ste. Foy Couillard that only existed from 1972-1974.

You can watch it at ICI Tou.tv (in Canada) or Amazon Prime (in U.S.).

“Extermination & Acts of Genocide”: Human Rights Watch on Israel Deliberately Depriving Gaza of Water

AMY GOODMAN: So, can I ask you, Bill Van Esveld, is this the first time that Human Rights Watch is accusing Israel of genocide in Gaza?

BILL VAN ESVELD: This is the first time that we’ve made a finding of genocidal acts in Gaza. It is not an accusation that we level lightly. We have not done this very often in our history. We accused the Myanmar military of genocidal acts against the Rohingya in 2017, and we found full-blown genocide against the Kurds in Saddam Hussein’s Anfal campaign in Iraq in the ’80s — sorry, in the ’90s, and we found genocide against — also in Rwanda in the ’80s. It is, you know, an extremely difficult crime to prove. It is, you know, mass killing deliberately to destroy people because they’re part of the group, not something we level lightly, but, yes, we found it here.