Show HN: Coinwall, a bitcoin paywall | Hacker News Reader

Show HN: Coinwall, a bitcoin paywall

coinwall.co

49 pointsmarcell29 comments

Very cool. One idea you might play with is the idea of debt. In other words: allow me to view the content for free a couple times, while racking up an "IOU".

Perhaps after the debt accumulates I'm forced to pay my freeloader's bill to continue seeing content.

Second: Go to where the users are. You should have Coinbase support.

Looking forward to watching where you take this :)

Re IOU system: that is an interesting idea! It would solve one of the big problems with micropayments, which is the mental barrier. Thanks.

Re Coinbase support: point taken; they are indeed one of the most popular wallets.

Excellent concept... but I could not use it. It says "To view 46 words of content, send exactly 0.00015612 BTC ($0.10) to 12smAWhdY9aMFyEenX6NLVZDend5WJgfVc". I paid with this transaction: https://blockchain.info/tx/047a379b7530f98876818540356b66964... And nothing happened, not even after 2 confirmations.

Yes, excellent concept, but also did not work for me. Also attempt to refresh the page asks for another payment. In this moment of weakness you wish there was a "refund" button on BitCoin :)

Do you happen to have the transaction ID on hand for the failed payment?

Also, if you have a refund address, I can send the BTC back. It is a small amount, but still :)

I payed it, it confirmed practically instantly, said "loading content...", and never got past that step. When I refreshed, a new paywall was in place asking for another payment.

Did you get a "payment detected" message on the client side?

Also, if you have a refund address, I can send the BTC back. It is a small amount, but still :)

"Coinwall is a zero-friction paywall that uses bitcoin."

A little bit ironic. Isn't paywall itself friction?

Given that you need the paywall, there's no additional friction. By that logic, doing anything is friction, compared to not doing it. Why breathe?

A friend of mine, Zach Latta made something very similar and posted to HN a while ago: https://news.ycombinator.com/item?id=6881757

I'm assuming the technology behind this is either of two things:

* An implementation of probabilistic nanopayments (https://en.bitcoin.it/wiki/Nanopayments)

* Massive amount of extremely small transactions.

I'd like to know if any consideration has been made for the amount of data hitting the blockchain when this scales. A flood of transactions will cause fees to rise higher than the principal payment.

I built something like this into my URL shortener a long time ago ( http://tny.im/toll.php ). However, it is nowhere as easy to use, uses the Blockchain.info wallet APIs in a way they were never meant to be used, doesn't have automatic (nor automated) payouts and I'm not even sure that it still works. I never really advertised it seriously. Since nobody ever really used it, and because it's not the main purpose of the service (it has enough feature creep already...), I am considering discontinuating the feature.

If Coinwall becomes popular (and I hope it does) I'll be damned :)

Cool. Good for Soundcloud or YT users that want to provide links to dl their content for a fee without requiring too much hoop-jumping. Even a way of locating some content just through the referral link would be nice... that way a user on their SC and YT pages can set a permalink, but provide the redirection addresses on coinwall. Or rather, coinwall could have a "Soundcloud/YT" referral url that the user fills in when setting up the download: it's preprogrammed to handle those referrals and even stats could be given on the download page and the site could offer top-10 lists of music and video.

Yea, I was thinking of adding file upload support for music/videos is a next feature. Having support for Soundcloud/Youtube/etc. URLs is a neat idea and would make for an easy UX.

Another idea is to have a "set your own price" w/wo a minimum price, like with Bandcamp, where the download is like a post-donation gift. Also, once paid, the purchaser may want to be able to leave an email address or message to get further discounts in the future from the artist as VIP fans.

Ah. It seems to link directly to the protocol address "bitcoin:" - and I don't have anything registered to pick up on that - making the button appear completely broken for me.

You should get a bitcoin client :)

Very clever. However I still think that any scheme that requires people to pay in advance is going to struggle. You're always going to be facing the "simulation heuristic".

Tinypass is another paywall service that accepts bitcoin payments. http://tinypass.com

Unfortunately bitcoin's potential for micropayments isn't so great at the moment, when the transaction fee is 5-10c.

It was lowered by 10x recently, to .5-.1c: https://github.com/bitcoin/bitcoin/pull/3305

It really hasn't been lowered. Most users aren't running the latest code, so you would struggle to ever get your transaction into a block that way.

Great concept. Experience still needs some work...

How does the verification work? Do I have to register to verify that I've paid?

The blockchain will take care of that! Just have to provide a different BTC address for each user.

No registration is required to pay or to make a paywall.

Verification is done by assigning a slightly different payment amount to each person. For example, if you are charging 0.00015 BTC, the amount 0.00015001 and 0.00015002 may be used to distinguish two payments. These amounts are cycled every ~15 mins.

Edit: Also, I may add support for BIP32 master public keys in the future. This would allow derivation of child public keys on behalf of the user, providing a unique payment address for each transaction. This is technically easy to do, the only problem is most people don't know how to access their master public key.

That is kind of confusing isn't it, because there's also a miner fee. Does your algorithm know how to subtract the miner fee to get the unique amount? Also, are your floating point operations (subtract, compare) done correctly?

http://floating-point-gui.de/errors/comparison/

Anyone who uses floating point numbers in a bitcoin project is doing it wrong. Bitcoins have a fixed (for now) level of precision. 1 satoshi is currently the smallest discrete amount of bitcoin that can exist.

The miner's fee is separate from the amount sent, this is easy to distinguish.

Any chance of dogecoin support? Given their community thrives on micropayments...

Ooo, I like this concept.

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