kator

I built one of these a couple of months ago using a rPI and a simple relay to control the 12v feed to one of these:

    http://www.super-feeder.com/csfmodel.html

Literally the code to feed them is a crontab:

    0 5,11,17 * * * /home/pi/bin/feed - > /dev/null 2>&1

Using this script in /home/pi/bin/feed:

    #!/bin/bash

    export PATH=$HOME/bin:$PATH

    (
        source gpio
        echo "Using pin 12"
        gpio mode 12 out
        gpio mode 12 out
        gpio write 12 0
        sleep 1
        echo "Turn On"
        gpio write 12 1
        sleep 20
        echo "Turn Off"
        gpio write 12 0
    ) 2>&1 | logger -p local0.info -s -t feed

    gpio write 12 0

    exit 0

    /home/pi/bin/gpio is from here: https://github.com/lasandell/RaspberryPi.git

I re-wrote it this weekend as a Openresty powered API (nginx+luajit) and put a web page on with a feed from the picam so my wife could look at the bowl and hit a button to dispense more if the cats needed it.

I was reading the article when I ended up taking a detour to watch the embedded video promoting IC's:

https://www.youtube.com/watch?v=z47Gv2cdFtA

As sad as the pollution is it's still quite amazing to imagine that in 1967 they were on the cusp of a revolution driven mainly by efficiency. At one point in the video they talk about magazine pages that have chips on the front and a schematic for a "real industrial application" on the back. This was literally the start of the "maker" revolution, it just took original makers like Woz to see it and many years of evolution so that people with minimal electronics training can build amazing things on the shoulders of giants before them.

+1

I built a nginx+luajit RTB bidder that did 168k qps on 8 cores. It smashed the C eventlib version and of course it crushed the Java version. Golang came in a close second but at the time with 8 cores I had to do crazy things to get it to pin to CPU's since the golang thread scheduling didn't seem very scaleable beyond 4 cores.

All I can say is when you work at your passion you don't work a day of your life.

I love hacking tech even on the weekends and after hours. If you don't then you might want to consider a new career.

I think a big part of why 30 years into my career I'm still learning is because to me this is my "fun". I don't want to watch 30 hours of reality TV. I'd rather build a cat feeder that uses OpenCV to identify which cat is eating and when the cat's feeding bowl is empty.

Recently my job shifted yet again to more management and my wife suggested I "take vacation and work on that iPhone app you were playing with a couple months ago". She knows I'm a much more enjoyable guy to be around when I have had a couple really nice zoned out hours pounding a keyboard to beg a computer to do something stupid I've come up with.

PS: When my wife saw this first thing she asked was if I could interface something like that to the cat feeder. :-)

Reminds me of dockercraft, discussed recently at: https://news.ycombinator.com/item?id=10584956

I have a raspberry pi controlled cat feeder I built and have been playing around with the last couple of weeks as a side project. I showed this to my wife and she said "Oh so can you make it so I can feed that cats while playing minecraft?" LOL

One more step closer to launchd?

I wonder if the other factor besides interest rates is the prevalence of algorithmic trading.

When I see these swings and I hear these "flash events" it reminds me of extremely fast decisions made by machines based on very small changes.

I'm curious is there an index where we can see how much trading happens almost unattended on a daily basis via algorithmic systems? I wonder how that would map against the last decade of "systemic changes" in markets?

I always focus on hiring for Attitude and Aptitude.

If you have a bad attitude I can't help you with that.

If you have aptitude and a good attitude we can teach you whatever you need to learn to be successful on our team.

What I know about every person ever is they came into this world with little to no knowledge, they had to learn to eat, walk, talk, run, etc. If we focus too much on a candidate's experience and background we miss out on their potential future value.

One of the greatest employees I ever hired was a pool man, literally cleaning pools for a living when I met him. He was a hobbyist computer hacker and I asked him how he'd like to do that full time. He learned and turned out to be an amazing asset to my team. I have many stories like this over my long career. It's not about the school you went to, or what social circles you hang out in, in the end it's about your passion and ability to learn and get shit done.

All this said I do worry that our systems are not creating the space for people to find their passion while they hone their skills and find a career path.

Reading this article when the author says:

  “the most effective advertisements of all are those with little or no rational content”

I thought of: https://en.wikipedia.org/wiki/Joe_Isuzu

Imagine that, ads I saw 30 years ago just popped into my head.

I have to admit I'm in adTech and when people ask me what the highest impact is to any campaign's success I don't talk about the next machine learning algorithm my data science team is working on. I talk about the creative, it's all about the creative (or message). I can find the perfect time, to show the perfectly matched advertisement to a single person, but if the creative doesn't connect with that person I'm just wasting the advertisers money and the person's time.

Funny when I read the image I thought the student was optimizing to less work. His way was faster "I can use multiplication strategies to help me multiply." Seems the student's strategy was to do less work by adding 5+5+5.

When I took geometry I often was burned by my teacher when she'd ask me to come to the board and solve a problem. She'd say "You can't do that we haven't gotten to that part of the book yet, sit down already!" It all just seemed to logical to me. Maybe I didn't know what "it" was called but it was logical and easy to work out.

Most of my math teachers treated me this way, they'd be upset with me because I didn't write 100 copies of the problem on my homework but I'd pass all my tests. I was constantly in trouble with my teachers often being reported to the administration as a cheater. One teacher made me take my shirt off he was so convinced I must have written the answers on a sleeve or something. All because I didn't miss a single problem on his test but never turned in a single page of homework to his class.

yes > /dev/mem

Funny but true, many people think computers are "smart". When I am confronted with this statement in the general public I always remind them: "Computers are fast, at well computing, humans not so much. Computers however are stupid, they follow my directions exactly as I give them and will keep doing the same stupid thing until I figure out my mistake."

When we have a computer that can read the original post and give estimates and comment here on HN I will be impressed. Until then it's just a faster z80 to me, amazing, don't get me wrong, the things we can do today with the power at our disposal starts to feel like magic. [1]

All that said it makes me sad when I find code that someone didn't bother to think through or even use the profiling tools available to maximize the amount of resources it's consuming. It's true that "premature optimization is the root of all evil"[2] however at some point it can be worth you time to review your assumptions and crappy code and give it a tune up.[3]

[1] https://en.wikipedia.org/wiki/Clarke%27s_three_laws [2] https://en.wikiquote.org/wiki/Donald_Knuth [3] http://ubiquity.acm.org/article.cfm?id=1513451

He is self-employed, all he had to do was hire himself. :-)

I've spent the bulk of my life self-employed and he realized it wasn't as scary as it looks from the outside.

Well I started in computers when I was 15. My dad was very worried and upset when I quit my first job flipping hamburgers at Wendy's and started programming full time.

Over the years he grew tired of his job, he went into management and that was just worse. He said he missed the problem solving of the day to day mechanic job. My mom had went back to school at 40 to get a degree in art and was having a lot of fun with computer graphics and over the years my Dad would tease her about paying the bills.

One particularly hard day my Dad handed his keys to his boss and walked out of the shop, never to look back. He ran into a project to help his church with their headquarters website and he said "It can't be any harder than working on a 318". And off they went, from that one to the next, now my mom makes eReader magazines and my dad sits and bashes away at sites and debugs problems.

One time he tried to tell me how smart I was and I laughed, I told him I've watched him tear a car down to the studs and find one broken part and put it back together from memory. Never looking at a manual, reading diagrams or even pausing to guess where one of a thousand parts went. He's brilliant, he taught me to break problems down to single variables, test and iterate. Clearly he's way smarter than I am, I'm just trying to mimic him. :-)

My dad went from being an auto mechanic to learning to code when he was 63 and he's 77 now and argues with me about Drupal vs Joomla over dinner. It's only one sample but I'm convinced him switching careers extended his neural plasticity considerably.

This page crashes over and over for me on iPad Safari iOS 8.4

Don't have time to dig in right now but I'm curious if is crashes for other people?

Almonds, what about rice?

Took me three tries but my wife got it on the first listen.

My wife picked them out almost instantly, it took me a couple rounds. I wonder if there is a gender difference or other things at play there.

Reminds me of the old days of KA9Q and pushing IP over packet radio. Tech has come such a long way this might actually be a real alternative. That said bandwidth management will become a real issue quickly since it's hard for the general public to understand the shared nature of a mesh.

Interview them all and get as many people on your team as possible to talk to them.

At the end of the day the most important decision a company can make is about hiring.

The second is about firing.

Do the math, which one has a better ROI?

I hire for Attitude and Aptitude.

If you have a crappy attitude I can't do anything to help you there.

If you have the aptitude and your attitude is positive, can-do, willing to learn, we can teach you anything you need to know or you can learn it on the job.

I too worry that "Cultural Fit" is becoming the new "don't like them" excuse of the day. I try hard to hire people who think about problems differently than myself or other members of my team. My hope is to get as many angles as possible to see problems from so we together as a team can find solutions that might not have been obvious if each of us has a homogeneous view driven by some bogus "cultural fit".

What I know about my life is I was born with almost none of the skills I leverage every day. From the ability to walk and talk, I've had to learn it all. I feel focusing too much on fit and skills is like judging a baby on how cute it is. Basically useless.

FYI Current peaks for RTB are about 2.5m qps world-wide today. Some exchanges are seeing as many as 100B impressions per day with mobile and display impressions combined.

RTB is an amazing challenge and way too much fun for those inclined to bang their heads against all sorts of problems you never run across in the "regular" world.

I've done some work on these systems, one of my favorite challenges is writing tools that segment impressions in real time, you have only 10ms to respond because you're augmenting the bid before others can bid. A RTB bidder typically has about 100ms to respond. When you're shooting for 10ms at 2.5m qps peaks you have to think about everything from kernel versions, network settings, pinning to processors, avoiding GC, logging to disk is too slow etc.

Years ago at a large car manufacturer I had an argument with the "Data Security" team about firewall settings. They had some crazy dumb ideas of what had to be on the firewall and it was constantly causing us pain. I went to visit this person in charge and argue my case. He was in another building outside of the "Secure Datacenter".. He argued with me for about 45 mins about how nothing leaves that data center and the firewall is our last line of defense. I pulled a 5Gb 8mm tape out of my pocket, dropped it on his desk and said "That's a copy of every single customer in our database and our entire parts catalog with all order history so much for your firewall".

The next day we had more intelligent discussions about firewall settings, and permissions on the mainframe for tape backups...

Additionally my favorite trick to this day when visiting a company is just plugging in a laptop to various random ethernet ports. I was recently as at a place where they have a "Guest Wifi" that changes passwords every week and the password is emailed to everyone. Sitting in a random conference room I plugged in and had 100% access to their corporate network. In today's work of IOT this is basically gross negligence to only rely on a firewall for security.

To think a firewall is much protection at all is to stick your head in the sand and pretend everything is ok.

I have often wondered what Jordi's[1] vision would really be like.. Maybe this is a peek into his world.

Imagine all these things, wifi, FM/AM Radio, iBeacons, cell towers etc.. It must be so noisy in the radio spectrum..

[1] http://en.wikipedia.org/wiki/Geordi_La_Forge

I'm surprised language wars didn't show up. It seems to me "X is better than Y" threads always get a lot of heat and light.

FTA: "Auto GCAS, which was developed by Lockheed Martin’s Skunk Works"

I just finished the book "Skunk Works: A Personal Memoir of My Years of Lockheed"

http://www.amazon.com/Skunk-Works-Personal-Memoir-Lockheed-e...

It was a great book that almost feels like the pre-scrum manifesto applied to building aircraft.

I literally started my career in a RadioShack computer center. It's sad to see them go out this way.

I built a program that automatically locks my OSX machine when I get far enough away from it. It uses iBeacon ranging and I have the beacon in my pocket. Debated on sharing with others but I never managed to clean it up enough to be proud of sharing it.