paradigmshiv

The teeth is what bothers me

There is some cleverness going on behind the scenes, so for a large database you wouldn't necessarily have the whole thing in memory at once. But one of the big selling points of Datomic is that you get to treat the entire database as a value, and when you configure your app as a Datomic Peer (the feature I referred to above), it loads most of the Database into memory as it is needed.

Datomic is an immutable database, written in Clojure. It's pretty cool, you should check it out.

The company behind Datomic (Cognitect, which also develops the Clojure language) recently started offering the database as a cloud service. This was something Datomic users had wanted for a long time, but one problem with the new service was that one of Datomic's primary features, i.e. having the database reside in memory with your application, was missing.

Ions is a new service that addresses this problem by allowing you to deploy your app to the same VMs that are hosting Datomic in the cloud (a "datomic cluster"). It's basically PaaS for Datomic-backed applications.

I'm a longtime Clojure user and I had some trouble understanding all this as well, so I agree that could do a better job with presentation.

> I wonder how many police officer killings are due to "suicide by cop".

I don't think this is really relevant, because "suicide by cop" is a great reason why police should not take the lead in responding to suicide threats. You never hear about "suicide by paramedic" or "suicide by social worker."

Ehh.... I worked for a long time as a mechanic on diesel engines. The engines are designed to conform with emissions requirements as they are written, not necessarily to be more efficient or cleaner. And of course some auto manufacturers have taken rather "creative" approaches to meeting these requirements.

Even with everything above board, the technology is not really there to make diesel a great solution for autos. First, the emissions equipment in modern diesel engines adds weight and reduces engine airflow, making them less efficient than they could be. In fact, today's small diesel engines are only 10-20% more efficient than gas equivalents, when in the past they have been over 50% more efficient.

There are three primary types of pollution that come from an internal combustion engine--carbon, which causes global warming; nitrous oxides, which cause smog, and particulate matter, which contributes to air pollution and also causes all sorts of nasty health problems. Diesel engines are better than gasoline on carbon emissions by virtue of being more efficient, although as I mentioned this gap is closing. Special catalytic exhaust equipment has been added to newer diesel engines to reduce nitrous oxides, but it's expensive and the environmental benefits are marginal. Particulate matter is addressed by burning the soot that comes out of the exhaust, again using expensive equipment that reduces efficiency, and AFAIK the science is still out on whether and by how much this actually reduces environmental/health impacts.

Some municipalities in the US have perhaps misguidedly banned diesel engines from their roads. The situation is a little different in Europe, where diesel engines are found in a much larger share of passenger vehicles. If Europeans drove as much as Americans did, their cities would all look like LA circa 1975. I'm not sure about car ownership trends in Europe, but I think it would make sense for any city that expects increases in car ownership to start regulating diesel more heavily.

This is basically what I do. I'm a supervisor for a county government, and spend a lot of my day at a desk waiting for the phone to ring. I'm still learning to code, so it helps to actually do something other than think sometimes.

To this end, because I can't install a programming environment on my work computer, I installed Linux on my 15 year-old Dell and use the secure shell extension for Chrome to connect. Being forced to do everything in a terminal has really sharpened my Emacs skills. I typically spend a good portion of my day secretly hacking away.