Are there still any ATMs in Japan that don’t charge fees for withdrawing with a foreign card?

I just got back to Japan for the first time in five years.

I seem to recall that that some ATMs here don’t accept foreign cards, some do but charge a fee, and some do and charge no fee.

I’m 100% aware of the fees my bank at home charges me to use ATMs overseas, I’m not asking about that.

I believe it used to be that the Post Office ATMs and the ones at 7-Eleven didn’t charge fees. But when I used my first 7-Eleven one this trip it did charge a fee. Googling, I have found that Post Office ATMs now charge a fee but since results were still saying 7-Eleven doesn’t charge a fee I can see such pages are not up-to-date.

Does anybody know which, if any, ATMs in Japan still don’t have a fee?

Bitcoin optional fees create transaction ordering problems?

I’ve tried to find a solid answer to this transaction ordering question and the practical and technical issues that do not seem solved.

My understanding is that after I create a transaction, I can choose to add a fee for miners to pick up my transaction. I submit it to the network for propagation. Miners look in the unspent transaction pool and choose which they want to include in a new block. I saw this Tweet which seems to confirm a transaction ordering problem – using the same transaction input for two transactions with the latter being a high fee and that one confirmed first. I don’t understand why several responders seem to to believe this isn’t a problem.

https://twitter.com/alexbosworth/status/1028031387201236992?lang=en

I am near 2 stores that accept Bitcoin. I spend an input at Costco with no or a little fee. It hangs in the mempool like above. An hour later I am at BestBuy and spend the same input but include a fee — and that transaction gets picked up and processed first by a happy miner.

1) Even if Costco waited an hour, there is no guarantee that my earlier transaction will be confirmed in a block in 10 minutes or 210 minutes. It’s still too long for BestBuy to wait 5 additional confirmations after the first.

2) There is no guarantee that even if that the first Costco transaction was picked up by a miner, that a second miner that picked up the BestBuy transaction a little later couldn’t complete a block which would eventually be in the longer chain. In that case too, the first in transaction eventually gets bounced off the chain.

Bitcoin core and transaction fees

I’m using combination of ‘createrawtransaction’ and ‘fundrawtransaction’ API calls to create my transactions. I don’t pass ‘feeRate’ option to ‘fundrawtransaction’ and rely on bitcoin wallet to figure out the fee. Is this a good strategy for mission critical system like payment system or I have to manually estimate transaction fees and not rely on functionality provided by bitcoin core?

As far as I understand if fee is too low for a network conditions then transaction may stuck in the mempool of some nodes. Even worse it may be expelled from some nodes while still remain in others. Is there any way to cancel such transaction and make sure no miner will ever pick it up? If not then what are my options when dealing with stuck transactions?

Can the fees in a coinbase be used to launder Bitcoins?

Generally Bitcoins coming from a coinbase are considered clean as they are newly generated. However while answering this question I realized that mining pools could offer to launder Bitcoins in the following (in its edge case even extrem) way:

Let’s say I want to launder 1 Btc

  1. I create a chain of btc transactions with a relatively high fee (1000 Satoshi per byte). In the extreme case I could even make an extremely large transaction by including a couple of outputs with large scripts producing 1 tx which has basically the entire amount as a fee.
  2. I send this (those) tx only to the mining pool that helps me to launder the Bitcoin.
  3. The mining pool then sends me an output from the coinbase to a new Address of a value less then the 1 btc (taking their share of the laundering operation) also since I wanted to launder I could receive several smaller payouts to various addresses.

Let’s say this is impossible due to KYC requirements of miners. Such an endeavor could also be achieved by solomining such a block by renting out hash power.

Of course such an extreme tx would already look suspecious but I could create a similar situation by spammimg tx during a high fee market (or even producing such a fee market by spamming.)

Somehow this picture makes me worry as it seems to me that criminals would not only be incentivised to do so it would also interfere with the entire ecosystem.

Am I missing some point here? Why has that not been done yet? In case of stolen coins (for example quadrica exchange, it seems to me that it would even be worthwhile to just create a mining operation for such an endeavor)

Escrow plugin? Or site with least transaction fees? [on hold]

Thinking of creating a quick, easy website where a buyer can have their transaction held until the seller and buyer verify the transaction has gone down.

I know escrow.com has a plugin for it which charges 0.89% I believe Freelancer launched one recently as well that requires more of a developer kit and implementation (actually i think that escrow plugin IS from freelancer now I’m looking at it – they own escrow.com haha).

Anyone use it? Thoughts etc?

Is there a stablecoin where you do not have to pay transaction fees?

I’m trying to build an application that makes use of stablecoins, but I keep hitting the wall of my users being stuck with the stablecoins as it requires them to have to pay the parent native token fees which could be bitcoin or eth. Is there any type of stablecoin where I can just send to my users and let them send it back to me without having to deal with fees.