the-alchemist

3 tháng trướcdiscuss

There's some really good analysis (both business and tech) from the Asianometry youtube channel (ignore the name of the channel): https://www.youtube.com/watch?v=RmgkV83OhHA&list=PLKtxx9TnH7...

the-alchemist

11 tháng trướcdiscuss

They don't pay much. $5k-$6k/mo for half time.

the-alchemist

năm ngoáidiscuss

Speaking of databases, has anyone run Bloomberg's db (https://github.com/bloomberg/comdb2) recently?

the-alchemist

2 năm trướcdiscuss

They go into detail on their technical decision making, very cool:

Choosing Clojure6 and Datalog7 was a calculated risk–but one which paid off. The Datalog model offered the simplest and most ergonomic queries, had strengths in graphs and relationships, and the entity model could easily transform to more standard formats. In–memory Datomic was chosen on the server, allowing complicated relational rule–based queries to map over tens of thousands of claims, linking sources to the attributes of entities. Using Clojure allowed for rapid prototyping and fast feedback cycles. Together, this allowed constructing arbitrary graph traversal queries, without having to round–trip from the database to execute recursive code, allowing the nature of traversing the domain model to be separated from the specifics of the relationship. How entities relate, and how relations work through time, could be developed as separate concepts. Using Datalog queries, it was possible to get every subordinate, as well as the time ranges they held true for, with a simple query like (subordinate-of ?a ?b ?start-date ?end-date)

the-alchemist

2 năm trướcdiscuss

can't wait for the https://jepsen.io/ report!

the-alchemist

2 năm trướcdiscuss

Had a similar problem with Aetna in NJ. I thought my situation was unique

the-alchemist

2 năm trướcdiscuss

I believe the term for this is "partial escape analysis" (PEA).

GraalVM is the SOTA in the JVM world for this.

Here's an oldish blog on this: https://chrisseaton.com/truffleruby/seeing-escape-analysis/

I'm sure PEA is better now, but it's not sure if it's moved beyond scalars (int, float, etc.)

the-alchemist

2 năm trướcdiscuss

Looks like a few folks are confused.

1. One of the underlying cryptographic principles is multi-party / secure-party communication (https://en.wikipedia.org/wiki/Secure_multi-party_computation). e.g., three people want to share their salaries to each other, but don't want the information to be traceable to back to the source.

2. Another is Steganography, hiding text in, say, an image, or audio.

3. You want to prevent the problems with Signal, Tor, Bitcoin, etc. This means, no "50%" problem like Bitcoin, no monitoring of exit nodes like Tor, no centralized distribution issue like Signal.

Imagine:

Alice "sends" a message to Bob by creating an account on Reddit and posts a cat meme which has the hidden text (steganography).

Bob knows how to find the text in that cat meme, and responds by posting something on Twitter, which Alice can read and decrypt.

All this is deniable (I didn't get anything from Alice!), available (e.g., Twitter goes down), and secure.

the-alchemist

2 năm trướcdiscuss

agreed! great blog

the-alchemist

2 năm trướcdiscuss

It wasn't even 5-4, it was 6-3.

The basic idea, AFAICT, is that _federal_ law should not punish _state_ crimes under this specific section of the law (§666). As noted elsewhere, there might be other laws on the books for bribes, but §666 doesn't apply here.

The distinction between "gratuities"/ "gifts" and "bribes" is artificial to me, as a normal person, but I understand that the law makes a distinction.

I'm sympathetic to the federalism argument (every state should have anti-bribery laws so that _states_ themselves can take them to court instead of waiting for the feds!).

But I don't understand why someone would explicitly write a law that tries to draw a fat line between bribes and gifts. Is that the legal equivalent of a bug? A bad law?

the-alchemist

2 năm trướcdiscuss

Also worth pointing out that the original Nissan Leaf is now at least 13 years old, a lifetime ago in lithium battery tech, and intentionally used very cheap cells to keep the cost down.

the-alchemist

2 năm trướcdiscuss

Very misleading statement.

First, NY Post is kind of a tabloid. You gotta dig deeper. Here's the actual study: https://uk-air.defra.gov.uk/assets/documents/reports/cat09/1...

I recommend reading it. It's actually pretty well done.

Secondly, the report itself and common sense dictate that regenerative braking on EVs (or hybrids) greatly decrease brake usage, therefore brake dust. Some EVs have "one-pedal" modes where you don't use the brakes at all in normal usage.

Thirdly, tires is a different calculation. This looks like a fairly unbiased source (https://www.emissionsanalytics.com/news/2020/1/28/tyres-not-..., https://www.nokiantyres.com/company/news-article/there-is-a-...).

Looks like tire issue is a toss up, and it depends on what the type of tire and how you drive. The much higher torque on an EV and a heavy foot will wear down the tires a lot more, but that has more to do with driver behavior than EVs.

Also, this whole issue is kind of a red herring because tractor trailers and heavy pickups and SUVs are a much, much larger source of brake and tire dust, and overall particulate pollution.

the-alchemist

2 năm trướcdiscuss

Don't quite understand the hate. This is very reasonable behavior for a compiler in 2024. I would even go so far as to say that a compiler should never execute any user code by default.

Imagine if gcc could automatically, by default, download some shared library and include it in the build because of a special macro included by a random header file on the system.

Of course, this change is optional (just add `-proc:full` to the command line) if you want the old, less secure behavior.

Also, Lombok is not affected because it's not an annotation processor. (Also, look at Immutables: https://immutables.github.io/).

the-alchemist

2 năm trướcdiscuss

Lombok is not affected by this, as it is not an annotation processor.

The most popular annotation processor that I've seen "in the wild" is the Hibernate Metamodel Generator (https://hibernate.org/orm/tooling/).

Also, Immutables (https://immutables.github.io/), my favorite Lombok alternative, is affected.

Of note, you can bypass this more-security-concious approach by just passing `-prof:full` to javac.

the-alchemist

2 năm trướcdiscuss

I would give the jextract tool a try. I believe it uses LLVM to parse the header files, so the generated bindings might actually be pretty good.

the-alchemist

2 năm trướcdiscuss

Java's FFI is currently a very low-level. As the article points you, you don't actually have to do this: the jextract tool will generate the bindings for you from header files.

I'm sure someone will come along and write annotations to do exactly as you describe there. The Java language folks tend to be very conservative about putting stuff in the official API, cuz they know it'll have to stay there for 30+ years. They prefer to let the community write something like annotations over low-level APIs.

Anyway, the GraalVM folks don't have quite the same limitations as Java, so they have annotations already (https://yyhh.org/blog/2021/02/writing-c-code-in-javaclojure-...):

    @CStruct("MDB_val")
    public interface MDB_val extends PointerBase {

        @CField("mv_size")
        long get_mv_size();

        @CField("mv_size")
        void set_mv_size(long value);

        @CField("mv_data")
        VoidPointer get_mv_data();

        @CField("mv_data")
        void set_mv_data(VoidPointer value);
    }

the-alchemist

3 năm trướcdiscuss

What a crappy article. One can't complain NYT is too pro-EV.

This problem is a combination of growing pains, uneducated EV drivers, old EVs with crappy batteries, some bad infrastructure, and EV manufacturers that don't put enough diagnostics.

1. Ask anyone who has lived in these kinds of cold temperatures. Cold starts in ICEs are always a problem. in upstate NY, you always need a pair of jumper cables ready. you might get to where you're going, and then can't make it back.

2. Different battery chemistries have different cold vs. warm characteristics. Surprise, surprise, the newer, better, more expensive battery packs don't suffer in the cold as much. The loss can be as low as 3% (Jaguar I-Pace) to 30% (Ford Mustang Mach-E, VW ID.4). See https://www.recurrentauto.com/research/how-temperature-affec...

3. EVs have two battery packs: a small 12V one, like a regular car battery, and the BIG one. If the 12V one dies, you can't start the car, even if the BIG one is good. (EV manufacturers should install better 12V batteries and provide better diagnostics for this kind of problem.)

4. EVs also have a "pre-conditioning" charge, where (massively simplified) battery warms itself to prevent damaging itself when it's too cold. This can drain the battery, but if the car is plugged in, it's not a problem, it'll just pull the charge from the plug (even if the battery doesn't need charging).

5. Sounds like a few chargers "froze" up. Just like gas pumps, but obviously it's a much bigger issue because there's always another gas station down the road, unlike EV chargers.

6. Most EV owners charge at home, and we just plug in all the time because it's easy, convenient, and we can pre-heat the car with a button on our remotes, saving on battery.

7. Some EVs use resistive heat instead of a heat pump for heat gen, which can eat a lot of juice, but it's not a big deal anymore because the battery packs are so big.

So, really, my takeaway is that Tesla and the other EV manufacturers need to:

- cold proof their charging stations (probably a simple "growing pain")

- educate their users a bit. (if the car won't make it overnight because it'll have to do a conditioning charge based on the weather forecast, WARN the driver!)

- use better batteries. this issue will fix itself as the better manufacturing techniques spread throughout the industry

the-alchemist

3 năm trướcdiscuss

"MY" == "Model Y"?

the-alchemist

3 năm trướcdiscuss

This.

We would all benefit from more cause and effect analysis in our media.

- Let's say we increase prices that we pay cocoa farmers, even double the price

- Is this extra enough to send the girl to school an hour away, pay for her books, etc.? If you pay the family more, how do you know they would spend it on the girl's education? Maybe fixing the water well or building a sturdier house is more important. Or paying off debt.

- The school is an hour away, the girl might not feel safe being away from home for so long without any adults. She might prefer being with her family. So... boarding school? Are the teachers qualified? (Go read about absentee teachers in Indian schools.)

- Also, if cocoa farming becomes more profitable, it might encourage _more_ child labor as parents pull their kids from school to work "on the family farm".

- If cocoa farming is profitable enough, it might invite a protection racket. Go Google for Mexican cartels and avocados.

Ironically, here in the U.S., we kinda glorify "working on the family farm", expecting kids to help on their parents' farms. Isn't that family doing something similar?

I am in no way glorifying child labor. I think it's sad and I wish I could adopt all these children and give them the quality of life I enjoy.

But complex problems require complex solutions. Unfortunately, we--humanity as a whole--have not found a universal solution to end human suffering as a whole, even the small subset of misery like child labor.

Historically, almost every country that has "developed" into an "industrialized" nation has had a very difficult, dangerous, violent learning curve. Kids in coal mines in the U.S., 18th century Dickensian English was a hellhole...

the-alchemist

3 năm trướcdiscuss

> Knocking on a friend's door (though he knows a same-age kid two doors away) would be considered out of bounds nowadays.

Yeah, the social dynamics of this kind of thing baffles me. I'm sure it's very neighborhood-dependent, but neighbors don't "check" up on each other either.

I think this is more U.S.-wide: it's not socially acceptable to knock on someone's door or ring their doorbell even if they're waiting for me. You're supposed to text that you're waiting outside. Doorbells are only for deliveries and unknown strangers (like selling something, politics, religious missionaries).

If it's not socially acceptable to knock on a friend's door when they're waiting for you to get there, then it's definitely not gonna be socially acceptable to just knock, see if they're home, say hi, and that's it.

the-alchemist

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