Dive – A tool for exploring each layer in a Docker image - <AUTHOR> https://github.com/wagoodman/dive <comment><USER2> This is amazing, thanks for sharing it! A very useful feature that I always missed but never actually tough about.

I've had a hard time understanding the slices on the beginning will be very useful for troubleshooting bad images also while optimizing image sizes.

Can probably help to understand problems like the one bug where the image size got almost a 2x increase after a CHOWN, because the slice is added again with different owner ( I think ;) ) would be so much easier to see with this.

Ref for the old bug [https://github.com/moby/moby/issues/5505](https://github.com/moby/moby/issues/5505)

<comment><USER3> We added a lib to a java image and the size went up by about 4x the library size, I spent a few hours trying to track it down to no avail. Hopefully this will help pin down the issue.

<comment><USER4> Let us know if it's a relatable issue. Might save someone else a headache in the future.

</comment></comment></comment><comment><USER5> Project idea: a Google for docker images.

Search for files by hash within all public docker images.

Find images that contain a certain piece of code.

Reverse engineering Dockerfiles for those that were built without.

<comment><USER6> The latter can be easily done in a few hours by inspecting the image layer metadata.

Every layer understands the command it was run in the Dockerfile to create itself. Just look at `docker history` and have a look at the "CREATED BY" field for human-readable output of the layer metadata, or depending on your graph driver have a look in /var/lib/docker/image/overlay2/imagedb/content/sha256. From there you can reverse-engineer a Dockerfile.

For layers that were not built using `docker build` (e.g. `docker commit`, OCI-compatible image builders), re-creating the exact command that generated that layer is much harder to do. The only information most tools will give you might just be the diff itself.

<comment><USER7> > Every layer understands the command it was run in the Dockerfile to create > itself

How reliable is this? Can it be modified after creation by a malicious party?

That is, if I get a wild docker image, can I trust the results of `docker history`?

</comment></comment></comment><comment><USER8> Can someone well versed in Docker explain in their own words what this does and why it is useful? Thanks in advance! I'm definitely not a docker poweruser...other than build start and stopping..

<comment><USER9> A docker image is built in layers that stack on top of each other. Think of each layer as a commit in a git repository.

This project takes an image and shows the list of layers (=commits) and for each layer (=commit) allow you to see what was changed (=the diff).

A bit like a git log for a docker image.

<comment><USER10> If OP looks up some Dockerfiles on docker hub, this will make more sense. Look at this mysql file for instance:

[https://github.com/docker- library/mysql/blob/696fc899126ae00...](https://github.com/docker- library/mysql/blob/696fc899126ae00771b5d87bdadae836e704ae7d/8.0/Dockerfile)

If two Dockerfiles use debain:stretch-slim as their base, docker won't download both base images twice. Each command in the Dockerfile creates an image. If you copy a Dockerfile and just change the last line and build them in order, the 2nd build will run a lot faster and you'll see in the output it pulls out "cached images" since it's already run those commands (docker build --no-cache always forced a full build).

If you start making Dockerfiles and playing around with it, it will start to make more sense.

</comment></comment></comment><comment><USER11> As others have noted here, this is why we use Nix [https://nixos.org/](https://nixos.org/)

</comment><comment><USER12> This is great! Docker feels imperative to me, and using this could help mitigate that.

Also looking into Nix to help my container workflow more declarative.

<comment><USER13> But a Dockerfile _is_ imperative. It just lists, in order, the steps needed to build an image.

<comment><USER12> It's declarative in the sense that the instructions are set in text. But what goes inside a Dockerfile might be imperative, like running apt-get to install packages (i.e., running steps in order).

<comment><USER14> _But what goes inside a Dockerfile might be imperative, like running apt-get to install packages (i.e., running steps in order)_

But...that too is done via the Dockerfile, via the RUN command to execute commands inside the container at run time. Or alternatively using the ENTRYPOINT command.

</comment></comment></comment></comment><comment><USER15> I have been looking for something like this for like 2 years. This will be most useful for experienced devs new to Docker that don't quite understand what's going on and haven't had time to read the specs on how docker works.

</comment><comment><USER16> Is there a smart way to make more layers than splitting everything up into modules and ADDing each one? Why doesnt docker have delta transfers yet?

<comment><USER17> Layers _are_ delta transfers. Maybe not as smart as they could be, but there is a lot of under-appreciated complexity hiding here.

<comment><USER16> layers are not delta transfers in my opinion, they are just new copies or removed files. its like saying sftp is delta transfer because you don't have to send your entire disk image every time. I love layers and dockers very nice reusing of base layers and such but i feel like delta transfers would dramatically improve my workflow and upload times.

<comment><USER18> > its like saying sftp is delta transfer because you don't have to send your > entire disk image every time

I see your point, but the comparison to sftp seems really off. Overlay2 [1] indeed works on whole file differences, just as sftp would do.

Additionally, I don't think making actual byte-level deltas would yield you much improvement on container size. It would also increase access time unless you keep a cache that doubles storage requirements per image. Dockerfiles primarily add files rather than change them, and actual changed files are often small.

[1] [https://docs.docker.com/storage/storagedriver/overlayfs- driv...](https://docs.docker.com/storage/storagedriver/overlayfs-driver/)

</comment></comment></comment></comment><comment><USER19> Nice!! have been waiting for something like this for a while. Gonna try this for sure.

<comment><USER20> just curious, how do you intend to use this? I mean, what problem does exploring each layer in a Docker solve for you?

<comment><USER17> "why does this small change increase the size of my image by 500mb"

<comment><USER21> A few people pointed me to this dive tool after I wrote up these notes on shrinking Docker images: [https://simonwillison.net/2018/Nov/19/smaller- python-docker-...](https://simonwillison.net/2018/Nov/19/smaller-python- docker-images/)

</comment></comment></comment></comment><comment><USER22> This looks spectacular. This could solve a large chunk of my challenges with Docker in one swoop. Really excited to use this!

</comment><comment><USER23> Is there a tool to compare 2 or more images to check which layers they have in common?

<comment><USER6> There's no tool I'm aware of, but with experimental features enabled in the Docker CLI you can use `docker manifest inspect` on each image manifest and diff the content. e.g. `docker manifest inspect ubuntu:latest`.

This requires that you have logged in to the registry, pushed the image to the registry and have `docker pull` rights for the image. You could also run a registry locally, push your image there and inspect your registry's storage db. There's just no CLI command to do that.

<comment><USER23> Thanks!

</comment></comment></comment><comment><USER24> Very, very useful. Thank you for sharing this!

</comment><comment><USER25> dude this is sick

</comment><comment><USER26> This is amazing!

</comment><comment><USER27> Good tool!

</comment><comment><USER28> Off topic but anyone notices lot of issue with Dockerhub recently? Such as image tag disappear :( randomly fail to push or take a very long time to pull</comment>


Fractons, for Real? - <AUTHOR> https://quantumfrontiers.com/2018/02/16/fractons-for-real/ <comment><USER2> I like that they talk about their favorite tools and toy models. In grad school, I had a number of toy models and I got to use some of my favorite tools in my research/thesis write up.

For me, one of my favorite tools was a form of perturbation theory which I could apply to all sorts of things. Didn't always work, and I think I annoyed my thesis advisor with it.

</comment><comment><USER3> > _Back in the early 2000s, a question that kept attracting and frustrating > people in quantum information is how to build a quantum hard drive to store > quantum information._

In the early 2000s, there still existed "Quantum" branded hard drives, in very popular use. [https://en.wikipedia.org/wiki/Quantum_Corporation](https://en.wikipedia.org/wiki/Quantum_Corporation)

At first I thought the image was a joke.

Nope; you're just old now if you remember "Quantum Fireball".

<comment><USER4> I still want to know who turned a "quantum change" from the very smallest change one can possibly make to something revolutionarily large (I bet it was some marketting guy)

<comment><USER5> This is an amusing meme/complaint, but it is not really correct. In physics "quantum" does frequently imply very small, but its fundamental meaning is a "discrete" change with no intermediate state. Hence, it is perfectly correct to use "quantum leap" to describe a significant development.

P.S. There are now plenty of real-world quantum systems that are centimeter sized. Check "cavity QED".

<comment><USER6> So is it sort of like how we use 'atomic' to mean a single discrete operation in programming?

[https://en.wikipedia.org/wiki/Linearizability](https://en.wikipedia.org/wiki/Linearizability)

<comment><USER7> Yes. The name "atom" literally meant "indivisible" in its original greek form. It's fitting for computations that go on undisturbed until completion.

</comment></comment></comment></comment></comment><comment><USER8> About halfway through TFA;

"Things start to get technical from here, but..."

Gee, thanks for the warning! </s></comment>


Voyager 2, launched in 1977, finds edge of solar system dented - <AUTHOR> http://news.yahoo.com/s/ap/20080702/ap_on_sc/sci_solar_system

<comment><USER2> Does anyone know what "north" and "south" mean in the context of the solar system?

<comment><USER3> To hazard a blind guess: pole the system rotates around + the right hand rule is North

(<http://en.wikipedia.org/wiki/Right-hand_rule>)

<comment><USER2> But isn't the solar system (and galaxy) relatively flat? Would it really be 8 billion miles to the heliosheath if you're going perpendicular to the plane of the solar system? Looks like I've got some astronomy to brush up on.</comment></comment></comment>


Let's write down the needed skills - <AUTHOR> https://amineafia.github.io/just-learn-this/ <comment><AUTHOR> I just started an open source github project with lists of the needed skills for interviews and hyped tech roles. help me fill the list and help "us" student identify the skills we need for our dream job!</comment>


Show HN: Learn C and its lower levels interactively, in the browser - <AUTHOR> I made a simple virtual machine that runs C in the browser.This project is made as an experiment to see if C can be learned easier if the lower level is covered in paralel.
Sandbox: https://vasyop.github.io/miniC-hosting
Tutorial part 1: https://vasyop.github.io/miniC-hosting/?0
More info: https://github.com/vasyop/miniC-hosting/blob/master/README.md
Please support this project: https://github.com/vasyop/miniC-hosting/blob/master/support.md <comment><USER2> You should put this in "Show HN: "

This project is amazing!

My hunch is that academia is already sniffing this and musing to adopt into their courses.

<comment><AUTHOR> Get notified when new tutorials are released [https://docs.google.com/forms/d/e/1FAIpQLSectFtg9jl4zkFZqPnQ...](https://docs.google.com/forms/d/e/1FAIpQLSectFtg9jl4zkFZqPnQkSRChNG7-I0qzR3247NRzdmAqEHCZA/viewform?usp=sf_link)

</comment></comment><comment><USER3> Nice, but some of the missing features really hurt:

I couldn't do a simple #define. This is pretty fundamental to typical C programming. One would also expect stringification, token pasting, and variadic macros.

I added a goto, and it won't compile. Yes, this is a valid and useful part of C, and must be learned by any C programmer. If you doubt this, count occurrences of goto in the Linux kernel.

I also couldn't do modern array initializers. I'll guess the same is true of modern struct initializers. These are important for producing maintainable code.

There seems to be no support for the restrict keyword. This keyword makes a dramatic performance difference.

<comment><USER4> It seems like this comment is missing the point of this project, which is explicitly billed as an experiment to test the viability of an approach. It also sounds like you may have more extensive C experience than the target audience.

But more importantly, every MVP is going to lack certain features that some folks deem essential. But when we focus on missing features, or worse, miss the point of a project ("you built X but what I really want is Y"), we discourage them or others from trying/sharing future experiments.

<comment><USER3> I sort of am the target audience: I'm currently teaching C.

The lack of important standard features means I can't just say "this is C".

For teaching, normal data type sizes are important. Being able to have static data is important. Beginners need to see how these things work.

I do applaud the effort. I think it is a great idea.

<comment><USER5> Beginners also need to know that a specific translation to machine or virtual machine instructions isn't the definition of the program's behavior.

If this was a good idea, Kernighan and Ritchie would have filled the pages of that book with PDP-11 instruction sequences accompanying bits of C code.

</comment></comment></comment></comment><comment><USER6> I think it is quite interesting, although I think you do have too much information on the tutorial (too much clicking to do). I think it would be better if you could provide a much simpler example that it would allow people to learn how to use the tool by themselves. For instance, maybe start with what a push means, etc.

The thing is that you have two levels of learning here: the compilation step and how the machine works. It could be better to start with how the machine works and eventually how to write programs for it..

Keep up with the good work!

</comment><comment><USER7> I know basic C but never digged into what happens below the surface. As someone who doesn't know these things I find the tutorial really well-made, with a clean and concise exposition.

<comment><USER8> I am also tinkering a bit (pun intended :)) with low level stuff, currently reading Low-Level Programming by Igor Zhirkov.

</comment></comment><comment><USER9> This is basically the coolest thing ever huge insane thanks for putting this together man, you are a true hero

</comment><comment><USER10> Awesome work!!!

Reminds me some of Compiler Explorer: [https://godbolt.org/](https://godbolt.org/)

</comment><comment><USER11> Have waited forever for something like this. So. Many. Things. Boil down to C.

Thank you thank you thank you

</comment><comment><USER12> Just a heads up: it works on Chrome but not on Safari

<comment><USER13> Looks like it's a blazor app (mono compiled to wasm using emscripten), so it should run in all modern browsers - what error do you get on Safari?

<comment><USER14> Mobile Safari gives me a blank page.

<comment><USER15> Same here. Had to check that I had JavaScript turned on.

</comment></comment></comment></comment><comment><USER16> This could be very useful to visually teach exploitation basics (buffer overflows, stack smashing, ROP).

</comment><comment><USER17> This is really fantastic. Looking forward to more tutorials. Thanks for sharing.

</comment><comment><USER18> This is a very well-thought out pedagogical tool. Can't wait for part 2!

</comment><comment><USER19> This is super cool and would be great for CS classes, well done!!

</comment><comment><USER20> This was great! Looking forward to them for loops.

</comment><comment><USER21> Very cool. Maybe add malloc() and friends to missing functionality.

<comment><AUTHOR> there is new

<comment><USER22> Not in C, there isn't.

</comment></comment></comment><comment><USER23> wow, absolutely amazing!

</comment><comment><USER24> Great tool! Thanks for making and sharing.

</comment><comment><USER25> These links are blank pages for me.

<comment><USER26> You might have to wait a few seconds. It's blank initially, but it shows the code snippet and compiler in 3 seconds on my laptop

<comment><USER27> I could not get this to work in Safari, but they do show up in Chrome.

<comment><USER28> Same, it's not working in Safari.

</comment></comment></comment></comment><comment><USER29> What is 1 in CALL 1?

</comment><comment><USER30> Not bad</comment>


CPU emulator in web browser (Arm/Mips/X86/Sparc) - <AUTHOR> https://alexaltea.github.io/unicorn.js/ <comment><USER2> The x86 example is particularly cute:

        xadd  eax, edx
        loop  -3

implements the Fibonacci series in two machine instructions (notice eax and edx have 514229, 832040 in them after you run the example, the 29th and 30th Fibonacci numbers). I first saw that in a book a friend got me for christmas; a hard copy of this site: [https://www.xorpd.net/pages/xchg_rax/snip_00.html](https://www.xorpd.net/pages/xchg_rax/snip_00.html)

<comment><USER3> I'm glad someone caught the reference. Indeed, I took it from the [xchg rax,rax] book.

Also, I have to apologize for the many bugs the demos have at the moment (annoying editor, missing features), I intended to post a Shown HN post at a later point in time. During the next days I will be taking care of these matters. By the way, these demos rely in Capstone.js/Keystone.js to assemble/disassemble machine code (if anyone is interested, similar demos can be found at [https://phi.nz/](https://phi.nz/)).

</comment></comment><comment><USER4> i wonder how performance of this (emscripten of Unicorn) compares with this much more flexible ARM emulator from a few years ago (which I am much more excited to use for things as I can easily customize the instruction fetch and memory access routines; it is even straightforward how to just hook system calls).

[https://github.com/ozaki-r/arm-js](https://github.com/ozaki-r/arm-js)

[http://biged.github.io/arm-js/arm-js.html](http://biged.github.io/arm-js/arm- js.html)

^ The latter link is a demo; click "Boot" in the upper left.

<comment><USER3> Probably that Arm-js emulator you mention is faster: Unicorn is based on QEMU, which internally does the translation by translating the guest machine code to an IR. After optimizing it, this IR usually gets compiled back to the host machine code, but thanks to the TCI [1] the IR can be directly interpreted anywhere without the need of a compiler backend. All these steps incur on an additional overhead that wouldn't be there if one interpreted ARM code directly.

[1] [http://wiki.qemu.org/Features/TCI](http://wiki.qemu.org/Features/TCI)

<comment><USER4> You say "you" multiple times, but I did not implement this other emulator: I simply found it yesterday while evaluating options for emulating armv7 on top of JavaScriptCore.

On the other side: this CPU emulator is written using high-level JavaScript, and I think some of its control flow is implemented using exception handling, whereas compiling Unicorn to asm.js will get reconstituted in modern broswers back to reasonable native code (and qemu is designed to be fast). I don't think it is clear cut which is faster.

(I would do a benchmark, but for my use case I actually am working with interpreted JS, which is massively different, and I had already evaluated that Unicorn.js wasn't flexible enough for my intent, so it is more of a curiosity than a question I would spend time to answer myself.)

<comment><USER3> My bad, I realized my mistake and was editing my message right before your answer.

Indeed, performance is not clear and probably depends a lot on the browser's JavaScript engine. I will try to find that out in the future with some benchmark.

</comment></comment></comment></comment><comment><AUTHOR> Demo for ARM: [https://alexaltea.github.io/unicorn.js/demo.html?arch=arm](https://alexaltea.github.io/unicorn.js/demo.html?arch=arm)

This is based on the Unicorn emulator (open source): [https://github.com/unicorn-engine/unicorn](https://github.com/unicorn- engine/unicorn)

</comment><comment><USER5> Does anyone know where you can

        1) find SPARC systems
        2) find what you need to do to initialize all components on a SPARC system

I'd love to write an OS for a SPARC machine one day

<comment><USER6> > where you can find SPARC systems

In case by "find" you mean "where are SPARCs still being used"... It is something of a niche, but all our missions in the European Space Agency use LEON processors; a design based on SPARC [1].

And since you mentioned OSes, usually it is either bare-metal stuff or RTEMS [2].

[1] [https://en.wikipedia.org/wiki/LEON](https://en.wikipedia.org/wiki/LEON) [2] [https://www.rtems.org/](https://www.rtems.org/)

</comment></comment><comment><USER7> _> With all that said, QEMU is an awesome project, which Unicorn was born from. However, Unicorn is not just QEMU, but offering a lot more because it has been designed & implemented especially for CPU emulation._

Couldn't they extend Qemu, or there was a reason for making a separate project?

<comment><USER8> From these slides it seems it started as a qemu fork: [https://www.blackhat.com/docs/us-15/materials/us-15-Nguyen-U...](https://www.blackhat.com/docs/us-15/materials/us-15-Nguyen- Unicorn-Next-Generation-CPU-Emulator-Framework.pdf)

would like to know more about unicorn as well.

</comment></comment><comment><USER9> Apropo Emulator.

1\. Is there any way to run SGI/IRIX and some IRIX software?

2\. Would a simple IRIX Software run on BSD/MIPS? I heard they are quite similar.

This project seems to be discontinued: [https://www.vanheusden.com/miep/](https://www.vanheusden.com/miep/)

They claim to be able to have an emulator, but as far as I know, expensive as f.... [http://www.vhware.co.il/](http://www.vhware.co.il/)

Any other ideas?

</comment><comment><USER10> Very cool. Needs RISC-V.

And 68000 :-)

</comment><comment><AUTHOR> They have a showcase page at Unicorn website, with a bunch of really exciting tools: [http://www.unicorn-engine.org/showcase/](http://www.unicorn- engine.org/showcase/)</comment>


Show HN: A community stock screener - <AUTHOR> http://cocompounding.com <comment><AUTHOR> If you check it out I think it's pretty self explanatory, but I'm happy to answer any questions.</comment>


GTD with Painter Chuck Close: "Inspiration is for amateurs. I just get to work." - <AUTHOR> http://www.43folders.com/2008/01/11/working-close

<comment><USER2> "I'm a nervous wreck. I'm a slob. I have no patience. And I'm rather lazy."</comment>


Useful kernel and driver performance tweaks for your Linux server - <AUTHOR> http://timetobleed.com/useful-kernel-and-driver-performance-tweaks-for-your-linux-server/

<comment><USER2> Saying, "epoll is already enabled in [the] most recent kernel[s], but some strange distributions (which will remain nameless) have this feature disabled," is cute, but it would be more useful if you named the distributions so people know if they need to worry with this or not.

</comment><comment><USER3> Most of these tips are to improve network performance which is useful for high traffic websites. However on typical normal servers the constraints often are cpu/ram/disk, not network bound. So i'd rather leave my server untouched.

<comment><USER4> Firstly - thanks for reading the blog post.

Some of the things mentioned help to reduce CPU usage so that the CPU can do more useful things (TSO, IOAT, DCA, NIC irqs, etc). ioat moves a _surprising_ number of bytes for the CPU. You might be surprised at how many.

I probably could have (and should have) included a bit more variety, though.

Thanks for reading.</comment></comment>


Meteor 0.5.0: authentication, user accounts, new screencast - <AUTHOR> http://meteor.com/blog/2012/10/17/meteor-050-authentication-user-accounts-new-screencast

<comment><USER2> Duplicate of <http://news.ycombinator.com/item?id=4666686> (which has some great discussion in the comments).</comment>


Japanese Scientists Create Touchable Holograms - <AUTHOR> http://english.ntdtv.com/ntdtv_en/ns_asia/2009-09-16/163021253061.html

<comment><USER2> I am baffled to see this story up again. In fact, this was introduced at SIGGRAPH a year ago [http://www.alab.t.u-tokyo.ac.jp/~siggraph/09/TouchableHologr...](http://www.alab.t.u-tokyo.ac.jp/~siggraph/09/TouchableHolography/SIGGRAPH09-TH.html)

I remember this because I must have jumped around for a week after seeing that video.

<comment><USER3> What do you mean by jumping around?

<comment><USER4> Probably jumping for joy, as any star wars/trek fan should.

<comment><USER5> Alternatively, if you jumped around energetically enough (like a Klingon, say) you might generate the acoustic radiation pressure needed to make your own touchable hologram. Of course the two theories are not mutually exclusive.

</comment></comment></comment></comment><comment><USER6> How many months until someone comes up with an application for this in the adult industry? As with home video and web streaming video, could be another technology accelerated by porn....

<comment><USER7> I'm not sure why you are being downvoted. There are plenty of non-pornographic applications, but the porn industry could very well accelerate the adoption of this technology. It won't happen in months, no, but I can see holographic porn becoming a reality within 10 years or so.

</comment></comment><comment><USER8> "Up until now, holography has been for the eyes only, and if you'd try to touch it, your hand would go right through. But now we have a technology that also adds the sensation of touch to holograms."

Clearly I missed something here -- what are they using to create the holograms?

<comment><USER9> Curved mirrors. So not movie holograms; you can't put anything behind the projections. That makes the illusion very fragile at some touch surfaces. The sensation technology has the same projective limitation, so you can't have anything else opposite to your hand.

Together, they could give a reasonable hemisphere of touch and sight. However, the touch technology is separate and will work with any hologram in a controlled space.

</comment></comment><comment><USER10> Touchless door and light switches appears to be used extensively in Canadian hospitals. Without any holograms though.

<comment><USER11> An isolated light switch on a wall is easy to produce with a sensor and marking showing where to wave your hand. A panel full of buttons and switches is another thing altogether.

</comment></comment><comment><USER12> I clicked expecting this to be one of those terribly misleading science headlines, but this actually sounds really cool.

I wonder how much this can be tuned to create a variety of "materials", or if it's limited to a simple novelty sensation like making your fingertips vibrate a bit when you touch it.

<comment><USER13> Yeah, this reminded me of Blackberry putting buttons behind their touchscreens to make them click, or the cheap touchscreen feature phones that vibrate whenever you tap something. Still very cool in this application though.

</comment></comment><comment><USER14> Soon we will all know the joy of accidentally creating a real-life professor Moriarty who we have to defeat using only our powers of deductive reasoning!

</comment><comment><USER15> I don't like how they call it "the sensation of touch," when it's really just the illusion of touch.

<comment><USER16> > The technology consists of software that uses ultrasonic waves to create > pressure on the hand of a user "touching" the projected hologram.

How do you suppose putting pressure on the hand creates the illusion of touch, other than by the sensation of touch? Would anything, for you, count as the sensation (and not merely the illusion) of touch, other than having an actual solid object there?

<comment><USER15> My point is you wouldn't actually 'feel' it, therefore you wouldn't get back the 'sensation' of touching something. Yes you would _see_ a response, but you would not _feel_ the response. Ergo, illusion.

EDIT: For your enjoyment, <http://en.wikipedia.org/wiki/Ultrasonic_sensor>, you simply do not feel ultrasonic sound waves.

<comment><USER17> No, the whole point of the thing is that you _can_ feel it (or at least they claim you can).</comment></comment></comment></comment>


A $10K tiny house 3D-printed in 24 hours - <AUTHOR> http://apis-cor.com/en/about/news/first-house <comment><USER3> I'm so surprised that people have not heard of the late R.G. LeTourneau. The man was a mechanical genius, and the father of modern earth moving machinery.

Here's a video of his Concrete House Machine from 1946: [https://www.youtube.com/watch?v=BpWjyZO2lPU](https://www.youtube.com/watch?v=BpWjyZO2lPU)

This was 70 years ago! I read about them in his autobiography "Mover of Men and Mountains". He went with concrete because it was cooler in the summer, and warmer in the winter. Seems to me the "Not Invented Here" mentality has been around for a very long time.

<comment><USER4> The idea goes back even further, to Edison in 1908.[1] His system used a large set of metal molds which latched together to make a house-sized mold. Then just pour in the concrete and go. The houses were quite elaborate, with lots of architectural detail, all the way down to bathtubs and picture frames. A few are still around.

There's no problem mass producing concrete houses. Or apartment buildings. Building shells aren't really that expensive. The interior parts cost more.

[1] [http://www.concreteconstruction.net/_view- object?id=00000153...](http://www.concreteconstruction.net/_view- object?id=00000153-968d-dbf3-a177-96bdeb600000)

<comment><USER5> >Building shells aren't really that expensive. The interior parts cost more.

And land in a desirable location with a building permit costs even more, if it's even available.

<comment><USER6> Can't beleieve I had to scroll this far down. Land prices in urban areas are set by ability to pay, so with cheaper construction you can pay even more to the land owneer! Prices won't fall in urban centres one cent.

The problem of expensive housing is man-made: by bakers lending enough fiat credit to match your surplus value.

<comment><USER7> If land prices are set by ability to pay (rather than willingness to pay), that could be a good thing for buyers.

A reasonable model for the seller is to sell to the highest willing buyer. Each individual purchaser has an ability to pay and willingness to pay and will presumably only offer the lower of those two prices.

If land trades on ability to pay rather than willingness, that means that the highest bidder would have been _willing_ to pay more but was only _able_ to pay what they settled on, and I don't see a significant problem. The buyer is presumably quite happy, having paid less than they were willing to pay.

The chief downsides I see in such a system is that either the buyer is not actually able to pay (they misjudge their ability to pay), or for the non- buyers who are out-bid by other buyers with a greater ability to pay. (It could be frustrating to only be able to pay $X while land or properties change hands at 1.5 * $X, but no reasonable seller will sell for 2/3 the market price, so...)

<comment><USER6> > If land trades on ability to pay rather than willingness,

Banks create fiat on request for a loan. It's infinite. You have to bid all your surplus value or someone else will, either a dweller or a speculator.

<comment><USER7> That still means that you were willing to bid that much, right?

I've bought two homes in my life. In neither case did I bid all my available funds and in both cases, I got a house that served very well as my home. (There were several other houses I bid on over the years where I didn't get the property. Two cases were bank REOs where the bank was unreasonable, IMO. Two other cases I was simply outbid. Life goes on.)

<comment><USER6> You were forced to bid more than others who were willing to bid as much as they can. That is where the price tops out. If you have more money than them you still had to pledge more of your labour because bankers extended loose credit.

Life does go on. And we have to work for longer for the exact same pile of bricks than our parents because of the changes in banking, gold std and the tech enabling tracking vast quantities of digital fiat credit.

</comment></comment></comment></comment></comment></comment></comment></comment><comment><USER8> A lot of people are commenting (correctly) that any cost savings achieved here are trivial relative to the land cost. I think this is looking at this tech too narrowly though. There are many areas of architecture that can be revolutionized by cheap, accurate mass-customization.

One example would be energy. Right now heat transfer and the transmission of daylight through walls/windows can be theoretically optimized to reduce energy costs simply by customizing the geometry of the windows and walls relative to their orientation and local context. We don't do so in architecture because the costs of customizing the geometry is too expensive. Architecture has a history of attempting mass-customization since the 1960s[1], but it's always been limited by the technology and realities of integrating multiple subcontractors and consultants. Those problems still exist, but the industry is changing pretty fast and I feel automated form generation, simulation, optimization, and production technologies are converging to a point when this could be achieved.

[1] i.e John Habraken.

<comment><USER9> The price of land is much lower if the entrepreneur goes big and build a whole new town from scratch. There are however some challenges with this approach. None the less, it's being done all the time in Asia.

<comment><USER10> The "build it and they'll come" approach to planned cities never seems to work out. It looks like a city has to form organically to be viable.

<comment><USER11> Where has it failed? China has a lot of cities currently empty, but many are being populated slowly.

China building unoccupied cities has more to do with the fact that the average Chinese citizen is not allowed to speculate or invest in much other than real- estate.

<comment><USER12> Like you mention, there are many almost empty cities, also called ghost cities. You can also argue that they are slowly being populated, but that doesn't equate with success.

They failed in that there was a huge investment to build them, but the expectations for these cities were never met. Additionally, there is tremendous upkeep or maintenance.

For example, those new roads are crumbling and require extensive repair work. Think of a road that is 5 lanes wide, but a 1 lane would suffice to serve all of the traffic. The unused portion will still degrade, even though it's not used.

It's kinda like buying a huge house before having children. You still need to fix, maintain and clean the extra square footage, even though it's not used.

</comment></comment></comment></comment></comment><comment><USER13> I think this should be primarily interesting for buildings with special form which are hard or expensive to build with traditional methods. The price is not the selling point here, at least not in Russia. Russia has a lot of cheap labor from the southern ex-USSR countries like Tadjikistan. So $10k for 38qm is not really cheap. You can build a 150qm two-floor house for around $25k. Also $277 for the foundation seems a bit suspicious, should be much more expensive.

"the radius of curvature of the TV matches the house wall curvature" pretty much looks like a PR stunt for Samsung. I wonder if they've actually chosen curved walls to somehow justify curved TV.

<comment><USER14> Yes, if those figures are converted to USD (I presume so as they're using the '$' sign without specification?), then they are so manipulated as to be worthless. There is no way to pour a foundation, even a small one, for $277.

I agree the formal implications are the interesting aspect. Creating an exactly equivalent design, with curved walls everywhere, would be phenomenally expensive with conventional practices.

<comment><USER15> > Creating an exactly equivalent design, with curved walls everywhere, would > be phenomenally expensive with conventional practices.

You could easily make a house with round walls today if you wished to do so. But you wouldn't because you'd curse yourself every day when you want to place furniture and lay floor coverings.

Curved spaces seem like a good idea until you actually try to use them.

<comment><USER16> Hell, even non-square spaces (or spaces composed of non-right angles) are a pain in the ass to effectively use. My old place had a main living area with a few 45 degree angles, and it really limited what you could do with it unless you were willing to lose several square meters of floor space.

</comment></comment></comment></comment><comment><USER17> I find the notion of 3D printing a house intriguing but it seems ultimately impractical. There are better ways to manufacture homes that can be componentized and transported for final assembly on site. One where I visited the factory was the BluHomes[1]. You can automate much of the construction of walls and wiring and finishing if you do it in sections.

[1] [https://www.bluhomes.com/](https://www.bluhomes.com/)

<comment><USER18> Prefab houses have been around forever. I grew up in one. I think my parents paid about $100k in 1989. The construction was:

\- dig a hole

\- pour a foundation

\- truck in the house in two halves

\- bolt the house together

\- do final wiring, plumbing

move the family in

I have no idea how much these kinds of homes are today, but their latest zillow zesitmate puts it at around $300k (on an acre of property)...so YMMV.

3d printing, in general, is expensive and better for one-off, or low-volume things. Mass manufacture techniques are hyper-optimized and beat 3d printing most of the time when you need to make >10 of the thing almost every time...this includes houses.

<comment><USER19> After a quick search on prefabricated homes and reading the Wikipedia article, I'm really not clear on what their limitations are. Most of them seem optimized for warmer weather? I would really appreciate some links describing the current state of prefab housing and it's practicality.

<comment><USER4> The basic limitation is how wide a load you can move by road and rail. That usually limits you to a double-wide house.

There's panelized construction, which is like IKEA for houses. This works reasonably well for rectangular houses. The joints can be a weak point, both structurally and as leak points.[1] Plumbing, wiring, and interior walls are best done at the factory, but that makes the connections complicated.

If you're willing to have exposed bolts and joints, it's easier. Butler Buildings makes industrial buildings and barns from prefab panels of corrugated steel. Those buildings are everywhere in rural America. They're strong, they go up fast, they can be purchased with insulated panels, and they last a long time. You can even get a fake brick exterior and a nice interior. But the result will look industrial.

[1] [http://www.huduser.gov/portal/Publications/PDF/path_panel_co...](http://www.huduser.gov/portal/Publications/PDF/path_panel_conntn_report.pdf)

<comment><USER20> > The basic limitation is how wide a load you can move by road and rail. That > usually limits you to a double-wide house

It limits the size of the individual module, but I've seen an entire multistory, city-block-size apartment complex built up from trucked in modules; limiting the size of the prefabricated modules doesn't meaningfully limit the size of the final building.

<comment><USER21> It's amazing to watch! There was a row of townhouses like that put up near my old house. They had a crane and a steady stream of trucks bringing in the modules. Truck shows up, two guys put straps around the module and hook it to the crane. When I was watching, they were on the second storey, so there were two guys on the roof that helped the crane operator drop them in place. Take the straps off, throw them down to the ground, and repeat.

Pretty incredible watching the entire storey of a block worth of townhouses being assembled in an afternoon.

</comment></comment></comment></comment></comment></comment><comment><USER22> Discussion on reddit from 2 days ago: [https://www.reddit.com/r/Futurology/comments/5xf7sf/a_russia...](https://www.reddit.com/r/Futurology/comments/5xf7sf/a_russian_company_just_3d_printed_a_400/)

Apparently the $10k includes electrical, windows, etc.

<comment><USER23> Thanks! I was already thinking that 4 people with a bunch of bricks can quickly raise a wall too.

edit: 2 people, 7h (including a 40min break), one wall: [https://youtu.be/gSM70WGbTiA?t=25](https://youtu.be/gSM70WGbTiA?t=25) This is what the innovative part of the project is competing against.

<comment><USER24> Laying brick is very quick. And if you are willing to do a full brick width as the wall thickness, you don't really need much further insulation IIRC. Stick built houses are not as durable and take longer, but as long as wood and labor are cheap, they will be popular. Drywall is also cheap, though takes multiple passes to finish.

Personally if I was constructing my home with my own hands, I would go for brick.

<comment><USER25> Even better/faster than brick is dry stacked concrete blocks: [http://www.drystacked.com/index.html](http://www.drystacked.com/index.html)

<comment><USER15> But ugly.

<comment><USER25> Not necessarily. Dry-stacked blocks require surface adhesion which can be dressed up anyway you want (e.g. smoothed and painted, make to look like stucco, etc).

</comment></comment></comment></comment></comment></comment><comment><USER26> This is not new. China already has company that can 3D print a real two-story house. See this [https://3dprint.com/138664/huashang-tengda-3d-print- house/](https://3dprint.com/138664/huashang-tengda-3d-print-house/)

This article also mentioned another Chinese competitor can 3d-print 6-story apartment and a mansion.

<comment><USER27> Another one here:

[https://www.theguardian.com/technology/video/2014/apr/29/3d-...](https://www.theguardian.com/technology/video/2014/apr/29/3d-printer- builds-houses-china-video)

</comment></comment><comment><USER28> While this is clearly an impressive technical feat, I can't help thinking of the carbon footprint of creating a house out of concrete, which is notoriously un-environmentally friendly, and difficult to deal with when the structure is no longer required. Hopefully a more environmentally-sound material will be used. There's not a single mention on that page of the carbon footprint of the building method used, and I think it would be interesting to compare physically identical (as much as possible) buildings of different construction (3d printed like this, bricks and mortar, pre-fab wooden/osb panels, etc), particularly when the tag line of the article is:

"We Are Building the Future Today."

<comment><USER29> It is an interesting fact that concrete itself is a carbon sink, and that it mitigates a bit the emissions associated with its production.

That said, I agree that it would be interesting to have a _independent_ study of the complete environmental impact of such a building, from its erection to its disposal.

I would instinctively expect a smaller impact from this kind of "lean" approach, though this might also create problems due to the economy of scale not necessarily being present.

</comment></comment><comment><USER30> Cool tech, but...

Curved walls only look good from the outside. Design looks like something someone who has never built a house before drew up. Things like a sofa that can't face the TV screen, or ostensibly a bathroom that you have to walk through the bedroom to get to.

Also everything looks very narrow. I want to see them build a real house this way, something with full-sized doors (36"), full-sized washers and dryers, something with 2 levels, something with actual electrical outlets (I see none in the video or pictures).

I can slap together a shed without plumbing or electricity in a day. Boasting about the price, showing electrical appliances, but not including the electrical wiring... let's be kind and just call that some "optimistic marketing." I mean... It doesn't even look like they have a real foundation... And small point... if they are going for speed, why are they using a roller to apply paint? Spray would do a better job and cut the painting time more than 50%.

<comment><USER31> Here's a video of them making a larger more traditional structure: [https://www.youtube.com/watch?v=ViqzfPW6TFo](https://www.youtube.com/watch?v=ViqzfPW6TFo)

Though part of the point is that you can use this to make more complicated structures with less effort and error; whether they are always appropriate is sort of a separate question.

I think they have included wiring costs based on comments here & on reddit, though their site seems to be down after the HN hug.

Personally I'm more interested in modular construction than 3d printing since it's much clearer how you scale that up to larger buildings, but this is still neat.

<comment><USER30> I don't see any electrical outlets in the photos or videos.

I also don't see the cost of the foundation included... looks like they built on top of an existing concrete slab but didn't add that into the cost. I don't want to rip on them too much, but if they start talking about time and cost (literally as the headline) and they aren't being honest about what it really costs... it's hard to trust anything else about the article.

Can it even be called a "house" without a heater? I mean... they aren't following any sort of industrialized nation building code at all here. No sinks, no bathrooms (can't tell), no insulation in the roof, no smoke alarms... Calling it a "house" and bragging about the time it takes to build and cost... it's moot if it's not really a house. That's all I'm getting at.

<comment><USER32> Bottom of the page gives the cost of the foundation -- $277. It also does have an insulated roof, heating, a sink, a bathroom, etc. Electrical, they probably used a wall chaser/cutter to put a groove in to lay the conduit, which was covered when they surfaced the wall. Finish work like that is really similar regardless of the house, and is not really different from what you'd do with a brick surface, etc.

<comment><USER33> $277 seems suspiciously cheap. A google suggests that should cost $5/sq foot, or $2000 for this house.

<comment><USER32> This was done in Russia where labor costs are a lot lower. Most construction workers make a fifth of what they make in the states, and I imagine related costs are also lower. So probably a lowball figure, but plausible.

</comment></comment></comment></comment></comment></comment><comment><USER34> Around here houses are still built on site, stick by stick. The only things built off site are the roof trusses.

I don't understand why all the walls, at least, aren't built in a warehouse and then trucked in. It could be built cheaper, more precise, with far less wastage. Holes for electrical, plumbing and HVAC could be already put in. Even windows can be pre-installed.

(I know that part of the problem is architects under-design houses, leaving it up to the contractors to figure out how to route electrical, plumbing and HVAC on-site.)

<comment><USER35> Same here, there are pre-built houses but they are ugly. It is even forbidden in some neighborhoods to put a pre-built houses.

I guess this is just because there is no company doing it properly and maybe no market for it.

<comment><USER34> There's no reason the factory cannot build walls for custom houses. The jigs and all will be computer controlled, anyway. Nor does that imply cheaply built or poor materials.

It's got to be an industry ripe for disruption.

<comment><USER36> Exactly. They already do custom roof trusses in factories along with standard sizes.

</comment></comment></comment></comment><comment><USER37> What is the outcome of housing this cheap? This is one more option in a growing list that includes inflatable concrete structures, and Tumbleweed houses, prefab cabins, etc etc.

Is this cheap enough to house people in third world countries. Probably not yet, but could it be on the way? And I'm sure construction costs aren't even the primary economic factor to solve...

Is it possible this trend could make vacation housing for affluent people disposable?

I love the idea of having a tiny house or even two I can move around, but I suspect, knowing me, that it wouldn't get used and would take more maintenance than I'm really truly interested in.

<comment><USER5> Building houses cheaply is largely a solved problem, and offhand I don't see any particular reason to think this is actually any cheaper than techniques that have been around for decades, in terms of producing a practical finished dwelling.

If you want to house a lot of people cheaply, build a big, ugly apartment building. Or twenty. No big deal. The cost comes from the fixtures, finishing, the land, and (most especially, in desirable areas) the building permits.

This is _cool_ , but it's hard to see what problem it's solving.

<comment><USER38> this house is much more cost effective. Here in CA, it's hard to build a house for less than 200$ per square foot (either due to laws or local labor conditions) - not even including land and permit cost.

<comment><USER5> > either due to laws

Right. If it was legal to build tiny, cheap houses, you could build tiny, cheap houses, including using this tech. But since it isn't, you can't.

The issue with housing in the bay area is __NOT __, by any possible stretch of the imagination, that it 's technically challenging to make small, crude houses cheaply enough.

Plus:

> not even including land and permit cost.

But you do need the land and the permit. And once you have those, why not build a nice house? It's sensible to try and use the scarcest resource most efficiently, and in coastal CA, the scarcest resource is neither building materials nor labour.

</comment></comment></comment></comment><comment><USER39> I have a slight feeling that this won't become very widespread on Earth - simply put, the thing is too small to be able to construct a house larger than a typical 1-family house.

However, taking such a thing and sending it up to Mars or the Moon, now there's a potential for "real" prefabricated housing.

<comment><USER40> Why couldn't you use 3 or 4 of them to make a larger house? Seems like as long as it can print your largest room you are Golden.

</comment></comment><comment><USER41> Oh man, I'd sure like me some Samsung Nano Crystal Color Revolutionary Super Ultra High Definition TV and a Samsung refrigerator with No Frost system, a Samsung induction stove, Samsung dishwashing machine, Samsung electrical oven, and maybe even a Samsung microwave oven. Not to forget the innovative Samsung AddWash washing machine.

I wonder why that is.

<comment><USER42> At last! A house-sized 3D printer that automates product placement as easily as wall placement.

</comment></comment><comment><USER43> At first it seemed to me to be expensive for a little not really practical house to live in. Then I figured out this is a tech demo and PR stunt and not an attempt to make affordable housing for people to live in.

I wonder how this compare to a yurt or straw bale construction.

<comment><USER44> But with this technology it seems like it would be straightforward to build a slightly larger, more practical house. Though I agree, I think building a house with at least one actual bedroom would have made a better demo.

</comment></comment><comment><USER45> I'd be surprised if this house meets state regulations for residential construction in any US state.

That'll be one of the biggest obstacles to 3D printed housing in the US. Even if you somehow get efficiency gains through 3D printing, it's going to require a different configuration depending on the regulatory environment, which varies by nation and state and county and city and topography, and changes every year.

These regulations affect every detail of the construction of your house, from the foundation to the window panes. Even details as innocuous as sink depth are regulated.

<comment><USER46> If you open the link, you'll note that this is in Russia; a lawless land where the government is constantly struggling to prove that you can run a business which isn't gazprom.

<comment><USER47> Europe is also relatively lax in terms of building regulations, it's only the North America which is hung up on having a rule for every little thing.

<comment><USER48> I'd beg to differ. From personal experience, in the UK you cannot breathe without getting planning permission.

Although, these days, not sure whether to legitimately include UK as part of a European discussion, sadly.

<comment><USER47> Yeah I'd agree about planning permission, but inside you can do pretty much what you like without issue. The US has rules such as the number and type of sockets you need to have in closets.

<comment><USER48> Holy crap, fair play. That would drive me insane.

</comment></comment></comment></comment></comment></comment><comment><USER49> This is really cool, but I'd love to know how durable a printed house is over the long term. Right now though, I think that there's a profitable niche for this sort of portable and low-labor-intensity construction in the defence and disaster-relief fields, where speed and cost are a higher priority than aesthetics.

I could easily see the US government (or rather, their contractors) using this technology when constructing bases overseas, especially in places in Afghanistan where workers don't just need to be paid, but fed, housed and transported at great expense.

</comment><comment><USER50> I'm working on buying land some land and building a house right now. The prices for a typical traditional way of building a house aren't that astronomical. I looked into some prefab but for a split entry or two story it's pretty hard to bring my costs down much lower.

I wish I could get my land prepped and then print it out cheap or dropped off but haven't found anything that can get me to the price point I want with ~2500 sqft other than doing the typical way.

</comment><comment><USER51> Oh wow, pretty neat and surprised it took just 24 hours. For some reason it reminds me a bit of the Monsanto House of the Future at Disneyland. I wasn't even born yet when they took it down, but randomly found videos of it on YouTube once. But it was a whole house made of plastic. Probably molded I'd guess since they didn't have 3D printers back then.

[https://www.youtube.com/watch?v=3qUkNZ5aJWE](https://www.youtube.com/watch?v=3qUkNZ5aJWE)

</comment><comment><USER52> Amazing.

Concrete is also amazing. I can't believe how wood and stick frame took over traditional housing methods.

<comment><USER53> Earthquakes

</comment></comment><comment><USER54> Carpenters roofers painters and plumbers are safe. This "printed house" seems to have required lots of hands. It is also so small that any reasonable team of humans could have built it in as short a time.

A better approach would be to have the robot print the concrete forms, allowing for humans to erect and fill them on the site. That might actually save on manpower.

<comment><USER55> Right, I don't see them bringing this machine on site and having it print something.

You have to move materials on site anyway, so I bet they simply prefab modular components and then assemble somewhere else.

They just want to show they can build any shape and even take electrical and plumbing into account as they build.

<comment><USER56> There is the technological achievement that not too many years ago most concrete came in trucks and was wheelbarrowed by hand and leg into forms. Then came the era of boom trucks where a crane like machine squirts out of a hose into prepared form. The logical extension is getting rid of the prepared forms. That's what this technology demonstrator shows.

I agree the "any shape" aspect is key in that they're probably going to do more engineering and repair work than anything else. So dig up a sidewalk for a repair they'll print in place a new sidewalk faster than someone can build a sidewalk form, minimal as that is, after all a sidewalk is pretty small compared to an entire house LOL. Or your cellphone tower taken out by tornado they'll print a foundation for a backup tower as fast as rebar can get tossed in, sit a couple hours, toss a tower on the foundation, and you're back on the air. Or exotic repairs to civil engineering accidents, maybe that dam in CA needs a herd of 3-d printers to make a new spillway faster than they could even construct the forms. This also might come in handy with tunnel boring machines, rather than making pre-made panels fit, you could print panels to fit the as dug hole, which is interesting to think about.

The CivEng side of the conversation with the concrete factory probably sounds like: There's some damage, we're not even sure how bad it is yet, no obviously we haven't built a form we haven't even hauled out the big rubble yet the crane just got started, OK send out your 3d printer to patch, we should be done demolishing and hauling out the broken chunks by the time your truck arrives.

Even better if they can print nicely enough to make it residential grade appearance, perhaps they can patch things to look nice, not merely be physically strong enough.

</comment></comment></comment><comment><USER57> """The construction cost of the printed house amounted to $10134, which is approximately $275 per square meter, taking in account that partners have provided the highest quality materials"""

Due to the wording of the sentence I'm not sure if the material is included in the calculation or not. But assuming prices going down and technology improving a building like that for 10-20k in 24h is an interesting proposition for on demand housing (even if it is just destroyed afterwards). Embedded sponsoring by Samsung aside I think the wall printed to match the curvature of the TV is an interesting example. This could be interesting for events/marketing booths etc.

Edit: This could also be very interesting for Hollywood for set building :)

</comment><comment><USER58> Looks cheap to build, impossible to modify or fix.

<comment><USER59> Yeah, that's typically the case with concrete construction. :-)

</comment></comment><comment><USER60> Tiny houses are great and all, but most articles, tv shows, etc two basic issues:

\- land \- hookups

Had this discussion today with someone enthused about a tiny home community until the land use rental fee came into play.

</comment><comment><USER61> Anyone read the short science fiction (soon to be non-fiction) story Manna.

Is this the prototype of cheap "terrafoam" housing for the poor ppl displaced from the society? ;)

</comment><comment><USER62> Awesome! Finally, Flintstone on HWY 280 will have some competition [http://www.flintstonehouse280.com/](http://www.flintstonehouse280.com/)

I can see artsy architects thinking up a whole new range of designs that escape the constraints imposed by established manufacturing and construction practices. Probably not as much not for permanent habitat, but for a garage, or a playhouse for kids.

</comment><comment><USER13> Video of the process:

[https://www.youtube.com/watch?v=ViqzfPW6TFo](https://www.youtube.com/watch?v=ViqzfPW6TFo)

<comment><USER63> That was the first video I've ever had to play at 6x its original speed!

</comment></comment><comment><USER64> Related: This House Costs Just $20,000—But It's Nicer Than Yours [1]

[1] [https://www.fastcoexist.com/3056129/this-house-costs- just-20...](https://www.fastcoexist.com/3056129/this-house-costs- just-20000-but-its-nicer-than-yours)

</comment><comment><USER65> Given the fact that climate change is the big deal, how much _energy_ did it take to actually build such a house versus the energy needed by a regular brick & mortar & human workers house ?

<comment><USER66> Well, I suppose it's not meant to replace traditional building methods/materials, but as it gets better, imagine the usability of such tech eg. for building a base on the moon.

</comment></comment><comment><USER67> Print the walls and let this guy to do the rest [https://www.youtube.com/watch?v=J_Uoq6JYKbw](https://www.youtube.com/watch?v=J_Uoq6JYKbw)

</comment><comment><USER68> Too bad that the article doesn't mention any electrical nor water/sewage installation. No wonder the appliances are depicted turned off.

</comment><comment><USER69> Great but I dont think it's the walls and roof that take time usually. It's the planning consent, foundations, utilities and internals.

</comment><comment><USER70> When people say, "All the manufacturing has gone to China!" show them this video, and say, "No, they've gone to robots".

<comment><USER71> I was just thinking this morning how all the stuff we get from china should be the first things we try to automate so we can't stop contributing to child labor.

<comment><USER43> China has been replacing human worker with robots for a while now. The reason stuff is made in China is not child labor but supply chain availability.

</comment></comment></comment><comment><USER72> Inventor: [https://angel.co/nikita-cheniuntai](https://angel.co/nikita- cheniuntai)

</comment><comment><USER73> Other people have mentioned the high embodied energy of concrete but there is also a problem with insulating this structure. I hope the PIR wasn't just injected into the cavity because that is a recipe for disaster. The zigzag cross bracing you can see will be a massive cold bridge which will cause cold spots that will develop mould patches inside. Concrete is not breathable (it is mostly impermeable to water vapour) but hairline cracks develop which make it capillary active and will allow water to be wicked into the interstitial space containing the insulation and then through to the inner face to cause damp problems. A standard concrete wall needs to be a minimum of 300mm of solid concrete to remove the chance that a localised crack will form right through the wall. Usually when concrete is used it is purely for the floors and structural frame for this reason. You do see concrete clad structures but these are typically decorative panels with a capillary break behind, or they are damp and leaky old 60's buildings. Paint systems are not the solution as they tend to fail within 3 - 10 years and then they just trap even more moisture in the construction. Conventional houses get around this problem with a capillary break, basically just an air gap between the outer wall and the internal insulation which is on a block or in between timber structure. The alternative, which is well understood in central Europe, is to use breathable materials such as calcium silicate blocks and wood fibre insulation.

It looks like it forms a structure that only works in compression because of the way it is laid down. Even if it is glass reinforced concrete I don't think there could be a good structural interface between the printed layers. This is why it doesn't print the roof and they don't show how they dealt with the lintels over the doors and windows. These must have been installed manually. If the window openings had been 3d printed then they would have needed gothic arches to get around the 45 degree angle corbeling problem which is inherent in compression structures and the roof would have looked like a gothic vault for the same reason.

Another thing that is needed to make this into a dwelling that won't go mouldy, is some kind of vapour control layer on the inner concrete face. You then need to wire the place up, but there is the problem of how to hide the wires internally. You don't want electrical cables to go through the vapour control layer where possible and you definitely don't want any cable junctions where there is a risk of interstitial condensation making the electrics 'go fizzy'. Did they have to manually install dry lining over the cables? Are the internal faces rendered over conduit and then plastered?

I think their costs are suspicious as well, I don't know about Russia but in europe $227 would barely cover one day of time for 1 groundworks operative let alone machine hire and materials for foundations. A recent project we worked on had £20,000 installed cost just for the gravel fill for the groundworks for 2 small houses.

As an Architect, I think CNC machined cross laminated timber panels are more interesting because the embodied energy characteristics are much better and they are capable of forming diaphragm structures that experience tension such as floor and roof planes. In general flat vertical surfaces are not going away any time soon, because they are ABI compatible with Furniture v1.0.

</comment><comment><USER74> I wonder about 3d printing with cob like materials.

<comment><USER75> I image using a similar jig, but with wider tubing and possibly mixing the straw in as clay mixture is being poured out. But how would keep the cob mixture consistent? Pre separated components, like the sand, clay, straw? Depending on how wet you apply it, you might need to take timeouts for layers to dry.

<comment><USER74> Yeah, lots of questions to get it right.

</comment></comment></comment><comment><USER76> I'd be interested to see how the process scales up to larger structures. That house is smaller than my apartment!

</comment><comment><USER38> Finally some real innovation! This is awesome.

Now, let's get this over here in CA - I know I'm just dreaming.

</comment><comment><USER77> You don't have to print a house - it better be built from Lego-like blocks.

</comment><comment><USER78> We need Elon Musk to ship a few of these things to Mars

</comment><comment><USER79> Great to build a large and long wall /s

</comment><comment><USER80> we should print on the moon using robots with no human aid.

this is what elon musk must send, not just an orbital tour.

</comment><comment><USER80> the housing crisis needs vertical buildings, I hope 3d printing can got in that direction soon.

</comment><comment><USER81> A house without plumbing

</comment><comment><USER82> What's the point of cheap housing if the landowning rentier class keeps extorting everybody through higher and higher rents?

The only way to get actually affordable housing is to tax land so hard that it stops being an investment at all and becomes merely a commodity, like it should be.

<comment><USER83> Nobody is extorting anyone. Rents are set by the market price just like anything else. Landowners can only charge what people are willing to pay.

If there is a problem, it's with the availability of land for building new housing. Zoning laws and NIMBYism artificially constrain the supply side of the equation, which drives up rents. There is no extortion happening - <USER2> supply constriction.

<comment><USER43> I'm not sure where you live, but right now on HN's front page there's a post about the housing bubble in Toronto and the 100k vacant homes in Paris. So what you say may be true where you live but it is not the case elsewhere.

Many people pay more than they were willing to or have to share their place to be able to pay rent. When the choice is between paying more than you were willing to or not having a place to live, you don't really have a choice.

<comment><USER84> I agree with your sentiment but not your language. Nobody pays "more than they're willing to" in economic terms. They have the choice to not pay rent and be homeless, and the price they pay in rent reflects their desire not to do that. But I'll agree that most people pay more than they'd like, more than is sensible and more than is fair.

<comment><USER85> People can also "choose" no to pay for food and eventually die of hunger. To describe paying for basics like its a choice is highly insulting to those who cannot afford those basics.

<comment><USER86> With the same morality it would be highly insulting to those who cant get food to worry about taxing properties in the city so middle-class have better access to them.

But even more, it would be more practical to understand why are people paying such high rents, not only because of housing supply, but because of the concentration of work in the cities, once again, making it way more sustainable to live in a city than in the country side.

</comment></comment></comment></comment></comment></comment><comment><USER87> This isn't useful because the printed house lacks wiring, plumbing, and finishes and is also an example of wasteful land use. The occupant of this house will indirectly demand roads, power, water, and sewer systems and most likely parking for a car as well. If we accept that housing has become critical issue then we need to take it seriously and look at the whole problem and what aspects are the most costly. Currently planning, infrastructure impacts, and labor intensive details are where most of the money goes. Basic construction is already competitively cheap.

<comment><USER58> Housing isn't a critical issue at all. Housing is large cities is a critical problem.

With the internet and modern transport infrastructure there's no reason to live in a big US metro area like SFO or NYC. The quality of life sucks and the cost of living is outrageous. I can be in midtown Manhattan with a trip about 20 minutes longer than the average Long Island commuter, and live in a bigger, nicer home in a better place that would be possible in the metropolitan area.

It's kind of ironic that we pay people on the other side of the planet to run our IT systems, but the average technology company insists on locating much of its stateside operations in a small number of ridiculously expensive places that increase cost and almost certainly decrease the quality of output. Car companies figured this out 100 years ago.

<comment><USER44> > almost certainly decrease the quality of output

I think this is a dubious statement. The bifurcation of American society, with increasing concentration of wealth in cities, and increasingly desolate rural areas, has only accelerated in recent years.

The fact is that most in demand knowledge workers _want_ to live in central urban areas. You say you can have commute "only 20 mins longer than your average Long Island commuter" \- does that mean your door-to-door time is over an hour each way? No thank you, I'd much rather live in a small apartment with a 15 minute walkable commute.

<comment><USER88> >The fact is that most in demand knowledge workers want to live in central urban areas.

That's definitely false. There are hot markets for "knowledge workers" in every American metro, and a hot virtual market that is more than happy to pay for talented developers no matter where they're located.

In local markets, salaries may be adjusted based on the cost of living, but in relative terms, valuable knowledge workers have a lot of opportunity and are compensated well for their work wherever they live.

You might be conflating "my classmates at the university" with "in-demand knowledge workers", but it's incorrect to assume that people who could match the profile of a recent graduate comprise the majority, or really even a substantial part, of the "desirable worker" market. Real-world experience is immensely valuable, and real-world experience is generally only found where age, the necessary corollary of experience, exists. That is frequently _not_ urban centers.

I know a senior developer who, in his mid-50s, left behind the Seattle metro for a quiet life in the mountains of Idaho. As long as he had an internet connection, his clients were more than happy to keep him on board.

I've spent my entire career in metro areas of respectable size, but not the "urban centers" or tech hotspots that you're probably referring to. There are good (and bad) developers everywhere.

>No thank you, I'd much rather live in a small apartment with a 15 minute walkable commute.

That works while you have 1 -- _maybe_ 2 -- inhabitants in your "small" (read: _tiny_ ) apartment. If you ever have kids, the impracticality of this plan will be immediately visible. This further suggests that you're constraining your view of "in demand knowledge workers" to the under-30 set. I suggest you get out more!

</comment></comment></comment></comment><comment><USER89> What's the point of cheap housing if people are going to spend all the money that is saved into unneeded new electronic devices or new cars?</comment>


Plagiarism, the plot thickens - <AUTHOR> http://jacquesmattheij.com/Plagiarism,+the+plot+thickens

<comment><USER2> I only worked with Harrison very briefly (and merely in the same office—I never worked one-on-one with him personally).

I reached out to Harrison and Zee on Twitter, first. I was irritated that he would do something like that, especially because he knows me. He ninja-edited the post and Zee went on a tirade; that was when I felt wronged. Harrison said nothing to me until much later.

Nothing manufactured, nothing faked, and nothing personal. By and large, I was upset with Zee's reaction.

<comment><USER3> I think the fact that the two of you knew each other previously makes this whole thing even weirder. After all, it would have been bad enough to do this and the subsequent reaction to a stranger but it to a friend makes even less sense.

</comment></comment><comment><USER4> I often wonder how much of the controversy we read about here on HN is completely manufactured by some clever individuals. NOTE: I am not saying the Joshua-Gross-Next-Web-situation is obviously manufactured. I have no idea.

I am saying controversy is a great way to drive page views and links. In some cases, those links are valuable to SEO. I like to imagine Michael Arrington, Dan Lyons, and MG Siegler sitting around a room and saying "Ok, what can we come up with as a good excuse to really yell at each other?" ... which is then followed by posts like these (and hey, they're getting another link now):

[http://www.realdanlyons.com/blog/2012/02/13/hit-men-click- wh...](http://www.realdanlyons.com/blog/2012/02/13/hit-men-click-whores-and- paid-apologists-welcome-to-the-silicon-cesspool/)

I may be way off. Maybe Arrington is always writing his honest opinion. But it surely happens somewhere on the web. Is anyone keeping track? Is there a website that has a list of all the seemingly-manufactured controversies? That would be interesting.

</comment><comment><USER5> _"First off, Joshua Gross was interviewed by The Next Web for an article by the same author, and more suprising, they actually worked at the same company in the past!"_

Busted! Who would of thought Hacker News would have been the leading source of investigative journalism.

I cannot verify that they worked at the same company from LinkedIn though?

However interview can be found here (as per submitted blog post): [http://thenextweb.com/apps/2012/01/17/stop-cluttering- your-i...](http://thenextweb.com/apps/2012/01/17/stop-cluttering-your-inbox- by-pasting-your-images-text-and-files-into-this-web-app/)

<comment><USER6> At least, in this article the TNW writer seems to know how to properly use quotes:

The creator of Hopper, Joshua Gross, tells TNW why he built it:

      <blockquote>I found that I emailed myself links and pictures
      constantly—whether I'm at another computer, at work, or
      mobile. I'd always lose these items in my inbox, amongst
      other new mail. Rather than continue to suffer with this
      really poor solution, I wanted a quick place to drop any
      temporary snippet of content quickly, but still be able to
      go back and search for it afterwards.

If only they had done the same in yesterday's article, they would have saved everyone a lot of trouble. They only thing they kept is the semicolon (:), which is not quite enough to indicate a direct quote.

</comment></comment><comment><USER7> Though it'll be interesting to see where this goes, it ultimately doesn't make me think better of TNW. It can only affect how I view Mr. Gross. Even then, it won't affect me much; the TNW author was a lesser character in the post, where the TNW CEO was the star.

</comment><comment><USER8> Harrison did tweet that he knew Josh:

"You're seeing one side @scherrymomin. @endtwist is/was a friend of mine. He found cool facts, I wrote about it & credited 2x, then a 3rd"

Also of note, thenextweb pointed out a much less obvious (in the text) case of plagiarism a month ago today:

[http://thenextweb.com/media/2012/04/15/netflix-amazon- apple-...](http://thenextweb.com/media/2012/04/15/netflix-amazon-apple-its- this-weeks-media-news-in-review/)

'And finally…

Nobody likes plagiarism, but an interesting nugget emerged this week. Poynter reported on a Fast Company blogger who said that he meant to steal from someone else when he was accused of plagiarism.

"Author Josh Linkner was busted for stealing the opening lines of a blog post by Chris Dixon. Now, Linkner did respond on Twitter and moves were made to amend the 'mistake', but the comment he posted to explain/justify the non- attributed use of someone else's text sounded a little…schoolboy-ish – he said a friend had sent him the excerpt. So let's assume a friend did send him the excerpt…why wasn't it attributed to him?

We'll let you decide what really happened…'

</comment><comment><USER9> Who cares. Why is this at the top of Hacker News? Seriously. What the hell?

<comment><USER10> Because a lot of us are bloggers, have companies with blogs, and/or have a vested interest in how people act on the web (because of our websites and stuff). This is an interesting piece of information about a controversy that surrounds an issue that affects us. The particulars don't but the concepts do, and the repercussions may.

</comment></comment><comment><USER11> Interesting bit of counter-astroturfing here. If you can't make yourself look better, use pseudonymous sockpuppets to drag them down with you.

I'll keep an eye out for use of this tactic in the future. Bookmarking for future reference.</comment>


Clang: Defending C++ from Murphy's Million Monkeys - <AUTHOR> http://channel9.msdn.com/Events/GoingNative/GoingNative-2012/Clang-Defending-C-from-Murphy-s-Million-Monkeys

<comment><USER2> As a reference, this video was posted 3 weeks ago with another title in <http://news.ycombinator.com/item?id=3565400>. But almost receive no upvote.

<comment> loup-vaillant Yeah, you need some luck to make it to the front page. If I recall correctly, one vote can be enough, but it has to be done soon after submission time.

Once you get past that threshold, karma skyrockets.

<comment><USER3> It gets worse because not many "interesting" people dedicate some time to /newest. I used to go there once every day. The main problem is HN doesn't discriminate by topic combined with lack of downvote. The noise to signal ratio is too high. There are way too many spam, blogspam and metoo articles against a few actual interesting submissions. And most times a blogspam article gets to the frontpage instead of the original source. It's a shame.

In reddit the people doing the honorable job of upvoting new stories are called "Knights of New". This effect is notable on good communities like /r/programming. Trash submissions quickly get downvoted.

</comment></comment></comment><comment> X-Istence I have been using clang for just over a year now and I have found that without it I start going insane. It is by far my favourite compiler. The error messages it spits out are sane (compared to those of GCC) and help me track down the problem faster and with less effort. It definitely has made me a very happy man!

<comment><USER4> Does anyone have a clue as to why GCC's messages have remained so bad for so long?

<comment><USER5> gcc's error messages, especially for C++ templates, got much better in 4.5. They don't have pretty colors, but I didn't find a substantial benefit from clang 2.9's vs gcc 4.5's for C++ development when using both for a week.

Note that if you're on a Mac, your system's gcc is likely several years out of date.

<comment><USER6> > Note that if you're on a Mac, your system's gcc is likely several years out > of date.

To be precise: Apple stopped maintaining its GCC branch after the switch to GPL3. The last version available with Apple patches is 4.2.1. There will be no further updates to this branch.

</comment></comment></comment></comment><comment><USER7> I use Clang everyday and the error messages, warning messages, and static analysis are really great to work with.

</comment><comment><USER3> Good talk minus the bashing of GCC and Stallman. It's a free product you don't need to use it and you're not entitled to anything as the license clearly states. The speaker pretends to be against open source politics but doesn't state his bias since both Apple and Google have corporate interests to undermine GPL compiler tools.

On the other hand, I really like the competition. It's very healthy to have options.

<comment><USER8> If clang takes off, GCC will take a lot more bashing, simply because meaningless flame-wars are the nastiest.

If there's a clear winner, you run with it. If the tools are really different, (i.e. Python vs. C), you pick the right tool for the job. If the tools do essentially the same thing in slightly different ways, with slight advantages and disadvantages in some areas (i.e. KDE / Gnome; vi / emacs; Linux / BSD) then you resort to ad hominem attacks.

<comment><USER9> So much wisdom in so few words, this was one of the times where just an upvote wasnt enough.</comment></comment></comment>


Ask HN - How many people do you follow on Twitter? - <AUTHOR>

I've been trying to keep my list shorter than 100. My concern, missing out on the important tweets and being spammed by the noise.<p>(Bot are bad but sometimes "social media gurus" are worse!)<p>How do you garden your twitter feed? <comment><USER2> About twenty, I think. I use Twitter to keep track of people who I know but aren't necessarily my Facebook friends, as well as a few personas (the Penny Arcade guys, for one) and a few eSports pros.

</comment><comment><USER3> Three strike rule: If I see three posts in a row that I don't find interesting from the same source, I unfollow them. It works pretty well for me so far.</comment>


YouTube Just Demonetized 75% of Our Videos - <AUTHOR> https://www.youtube.com/watch?v=dX4dDh-EGyI <comment><USER2> "of our videos we uploaded yesterday, not of all of our videos"</comment>


I Lied. I Made the Whole Thing Up. Now I'm in Trouble - <AUTHOR> https://medium.com/@IamShaneMorris/i-lied-i-made-the-whole-thing-up-now-im-in-huge-trouble-e59da5831105 <comment><USER2> I sort of, like, predicted this:

[https://news.ycombinator.com/item?id=19985191](https://news.ycombinator.com/item?id=19985191)

<comment><USER3> Hey, me too! Nice work, team!

Now he's only lying about... the movie industry being interested (there's nothing special about this story, I guarantee that nobody important cares), the whole interaction with his "weed man", and... probably everything else too. _Maybe_ he's staying at a friend's house because he's scared, but that's about the only thing I'd believe at all.

</comment></comment><comment><AUTHOR> Crazy that he lied...but is that a lie to cover it up?

He received offers about turning it into a movie (apparently)...does the lie make it a better movie?

<comment><USER2> The safe assumption would be that he's lying about that too.</comment></comment>