Micree Zhan Bitmain

While Bitmain is one of the most important companies in the Bitcoin industry, not many people realize the company has two CEOs. Most of the public statements over the years have come from Jihan Wu, and less is known about Micree Zhan, who is the more technically-inclined of the two.

In a recent interview with CoinJournal, Zhan shared his thoughts on Segregated Witness (SW), Bitcoin Unlimited (BU), the role of miners in the ecosystem, and much more.

CoinJournal: Not many people in the Bitcoin community (at least outside of China) know much about you. What is your background and how did you get into Bitcoin?

Micree Zhan: I am an electronics engineer and before co-founding Bitmain, I ran a startup that was also related to [integrated circuit] design. In 2013, Jihan introduced Bitcoin to me and, after spending about two hours to understand its basic idea, I knew it was the right thing to do.

CJ: What is your main role at Bitmain? I’ve heard you are the technical guru.

MZ: Yes, I focus on the products and the engineering departments at Bitmain.

CJ: What do you think about Bitcoin Unlimited’s concept of emergent consensus? Should the miners activate this change? Is this something the users should support?

MZ: We know that bitcoin block size is reaching its 1M limit, and many proposals were introduced to remove this limit. BU’s emergent consensus is one of these good solutions. So far, emergent consensus is getting more and more support in the community. I believe emergent consensus is easier and more feasible than SW and that many miners will activate it.

I believe Bitcoin users should support BU too because BU provides another Bitcoin protocol implementation code. The basic consensus and value of Bitcoin is its unique ledger, not the unique code from Core.

CJ: Did Bitcoin.com’s recently mined invalid block due to a bug in Bitcoin Unlimited change your thinking on Bitcoin Unlimited and/or emergent consensus?

MZ: No. As an engineer, I don’t think there is a software product without bugs. Fortunately, this bug caused only a small loss. We should support good alternative Bitcoin protocol implementations to make the Bitcoin network stronger. When there are various implementations on the network, a bug from one implementation will only affect some of the nodes, not all nodes. In addition, when a bug of one implementation is active, the nodes will have a choice to change to another implementation. When a bug is active, emergency activity and leadership of the developers becomes important. I believe that the BU developers did a good job in timely solving this problem, just as the Core developers have previously done.

CJ: What do you think about Bitcoin Core’s Segregated Witness proposal? Should the miners activate this change? Is this something the users should support?

MZ: SW is a very smart idea, and it will be helpful for Bitcoin. However, SW is a little complicated, and the community need more time to evaluate and test it. I don’t think it is safe to activate it today.

CJ: Are there block size limit proposals unrelated to Bitcoin Unlimited and Segregated Witness that you would support?

MZ: I prefer BU for now.

CJ: What do you think about proposals to increase the block size limit through the use of extension blocks? Is that something you would support or do you think it has the same sort of complexities found with SegWit?

MZ: Many good solutions for scaling the block size have been proposed in the community and these solutions include those of extension blocks. The solution of extension blocks is beautiful from a technical view. However, many such solutions have lost support and, I think, it is often not because of any technical issues with these solutions.

CJ: There seems to be a debate over the role of miners on the Bitcoin network. Some say they should only react to the desires of users, while others say they should lead and implement changes proactively. What is your view on this issue?

MZ: I think we shouldn’t put the burden of any of these moral decisions on miners.  The most important thing for miners is the economic benefit of mining. Mining is a marvelous design for Bitcoin generation and Bitcoin network stability. The higher the number of miners and the higher the network difficulty, the safer the Bitcoin network becomes. As long as the number of miners who are mining for their economic benefit keeps increasing, the Bitcoin network will continue to be safer. In 2016, we created an open-source Bitcoin mining pool BTC.com in order to make mining simpler and more efficient.

CJ: If miners should not have the burden of moral (protocol?) decisions, then shouldn’t miners be signaling for SegWit? Roughly the entire Bitcoin ecosystem seems ready for SegWit (Coinbase, BTCC, Blockchain.info, Xapo, etc).

MZ: Bitcoin is a wonderful and complicated system where all players (users, miners, exchange platforms, developers, and so on) have different interests. According to Satoshi’s original idea, it is important for miners to benefit from mining. Actually, miners invest considerable financial and other resources into their mining operations for the mining reward. I believe that they will consequently select SW or BU based on their interest i.e. to increase the block size, to make Bitcoin more popular, to get more transaction fees.

CJ: Feel free to share any other thoughts related to Bitmain or Bitcoin.

MZ: At Bitmain we will continue to try our best to make Bitcoin healthier and stronger.

Note: The order of questions from this interview has been rearranged for continuity.


          • ethereum had a problem before three months through a spam attack with smart contracts.
            Ethereum is a great example for what happen when you have unskilled developers to maintenance a system and especially what can happen when you do a hard fork without consensus.
            On the other hand is true that everyone in Bitcoin community release the problem with full blocks.
            the point is how can we solve it without risk the money of others ppl.
            Imo BU is a very poor in tech terms solution with many flaws.
            For sure we must first try to find space in the current blocks.
            Segwit and snorr signature is a first step.

          • “for sure we must first try to find space in the current blocks.”

            It is just your opinion. Mine is different.

            I always remember the immortal words of Knuth (spoken in the seventies)
            “We should forget about small efficiencies, say about 97% of the time: premature optimization is the root of all evil. Yet we should not pass up our opportunities in that critical 3%.”

            SegWit is a solution for the malleability bug, not for increasing transactions. I was there when they suggested it for malleability. They started to push it for increasing transactions year(s) later.

            The same is for Snorr Signatures. It is a solution to a different problem and not for increasing the number of transactions.

            The best improvement in the number of transactions you can obtain with both together (if every wallet adopt them and every one use them – this will require years) you can get with 4 MB blocks.

          • x4 the space of bitcoin blocks, fix malleability and all of them with simple a soft fork that anyone can have the choice to use or not use and with back compatibility.
            What problem you have with this?

      • The primary value-add of Segregated Witness is not as a block size increase, but rather as a transaction malleability fix, which enables off-chain scaling solutions that provide orders of magnitude greater scalability.

  1. Great to see Bitmain continue to support Bitcoin Unlimited with words. Can’t wait for them to upgrade their pools. I wish Kyle Torpey had asked about the new, huge mining facility that Bitmain is building. It should have been ready in december. What’s the status?

    • with 30% of hashrate and support from minority in bitcoin community you can only hard fork your selves from bitcoin network.
      And i hope to do it and leave us. No one need a conspiracy lunatics to a tech network.

    • Zero… But this “skilled” CEO think is OK. And if a CEO think is OK then is OK…. 😛
      I cant see what you didnt understand here 😀

  2. ” it is important for miners to benefit from mining. Actually, miners invest considerable financial and other resources into their mining operations for the mining reward. I believe that they will consequently select SW or BU based on their interest i.e. to increase the block size, to make Bitcoin more popular, to get more transaction fees.”

    To me that statement means miners will choose which ever protocol they think will make them more money. As miners cannot control the ever increasing volume of miners and difficulty, it seems like miners are looking for transaction fees more then block rewards.

    The comment about bigger block sizes will make bitcoin more popular (same point ver and bitcoin.com try to argue) is just bollox, having a bigger block size will not make bitcoin more popular, it will help confirmation times, but that’s about it, and who cares about confirmations really, companies have already started to clear funds before a transaction is confirmed. Only high value transactions need to be confirmed and then you pay the low fee (compared to other methods)

    I don’t favour either options really as their differences are not being explained in layman’s terms for the masses to fully understand. At present it’s just like picking a football team to support, with only very knowledgeable Dev’s having a full understanding of the differences.

    Why are Dev’s not testing the sht out of their proposed solutions to show they work?

    Personally I think it’s still early days, and bitcoin is still in the “paper cheque” stage, just like Fiat years ago, you paid by cheque and had to wait days for it to clear.

    • Are you dense?

      Bitcoin need bigger blocks because it need to accommodate more people and more transactions from the current users.

      Your statement is like telling a family a crappy 40 square meters apartment with one bathroom is good for one person, two person and a family of ten persons.
      Good luck with it when two of them need to crap at the same time.

      Enlarging the blocks is like enlarging the house, adding more restroom and living rooms (for the same people) and more bathrooms (for more people) is not the same.

      Yes, you could crap in a jar in the bedroom, and empty the jar in the bathroom once a day, but it is a crappy experience overall. And hope the jar never drop and break.

      • Anyone that need to use a poor solution for this problem is free to fork off from the network but not expect the rest of the bitcoin network to follow them.

        • Yes, and right now both solutions on offer are poor solutions. Unless a solution has a road map right up to being able to handles 1million transactions a second in future with moores law, then it is not the solution everyone is looking for

      • No mate, your not getting it, my point is there is no valid argument for either at present time, if the solutions on offer are not one stop solutions, then they are not the solution everyone is looking for. Increasing the blocksize(BU) will not increase the user Base which is BU’s main argument, all it will do is increase microtransactions, and we are quickly back to square one, segwit has not been fully tested and there is no plan after segwit, apart from it allows 3rd parties to centralise transactions off chain. To me you seem like a sheep just picking a side and shouting about it. It seems bitcoin is getting just like the BS politics show the air on news channels. Everyone screaming for their team with no knowledge of consequences. For crypto ‘s to replace Fiat they will need a gold standard which will be bitcoin, it will be impossible for bitcoin alone to replace every Fiat currency globally, but if bitcoin is the gold standard of crypto ‘s, then altcoins can be backed or valued by bitcoin. You really need to think of the bigger picture when it comes to countries, states and cities and giant corporations, all of which could issue their own altcoin, but if all Fiat is gone what medium do you use to value each and every altcoin. Stop making comparisons and actually think about how big Fiat is globally and the monumental task bitcoin has to replace them all, bitcoin will have a very long road map which bitcoin must change and adapt during certain times, and bitcoin cannot do it alone.

  3. For everyone complaining for the size of blocks on this page:

    Just the image on the top of the article is 300 KB (1/3 of a block now)
    How much it took for you browser to load it?

    This page alone is easily 2 MB to download just because of the fancy graphics.

    • because the talk here is pure technical and not politcal.
      What is the block size that you think can bitcoin network handle?
      Because atm in the p2p network system there is a limit how a block size can be and relay fast and to all the nodes of the network.


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