Technical writer @bitcoinoptech, co-author Mastering Bitcoin (3rd ed.), and grant committee member @bitcoinbrink. Opinions are my own.

Hilo, Hawaii, USA
If this tweet is pinned, I'm taking a break from Twitter. I'm probably still reading and replying on Nostr, and you can always contact me directly by email (see the website on my profile).
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I'm pleased to announce that Mastering Bitcoin (3rd edition), co-authored by @aantonop and myself, has been sent to the printer. Ebooks should be available around Nov 15th. Print books should be available by early December. dtrt.org/posts/mb3e-announce… (1/8)
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Replying to @socrates1024
You gotta get them when they're young. At 78 years old, my Grandma's first computer ran Debian. Three computers later and only a few months away from turning 100, she's still running Debian.
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Even knowing how LN works, watching frenzied activity on satoshis.place made me wonder about the mempool. Were all those people opening channels driving up transaction fees? The answer it seems is no. LN enables silly fun like cryptokitties but without killing capacity.
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Hey @CoinbaseSupport, I tried to close my account but your website is broken (like usual). Please fix (or implement segwit, stop promoting scams, don't make insider trades, provide cryptographic proof of reserves, don't complain about scaling when you crash every rally, etc...).
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I disagree. @LukeDashjr has cost valuable Bitcoin contributors more than than most people can imagine. He manufactures controversies over inanities, abuses his authority, and tells half truths that take time and expertise to refute. I think he's been a net negative for Bitcoin
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Wrote an article for the Bitcoin Wiki with a list of techniques for reducing transaction fees. It's aimed at wallet devs and organizations (rather than individual users) since many of these techniques require software support: en.bitcoin.it/wiki/Technique…
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Pleased to announce that @OReillyMedia has published an early release of the first two chapters of Mastering Bitcoin, 3rd Ed., which I've had the privilege of updating based on @aantonop's previous editions with the support of dev editor @angelarufino1. learning.oreilly.com/library…
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If you generated a wallet using Libbitcoin's Bitcoin Explorer, including as described in the appendix to Mastering Bitcoin, your funds are at risk (or already stolen). Full details: milksad.info/
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Mastering Bitcoin, third edition, is now available on GitHub under a CC BY-NC-ND license. github.com/bitcoinbook/bitco… The credit for getting this on GitHub goes entirely to @aantonop . It would not have happened without him.
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Launch announcement for btcinformation.org, a community-maintained fork of Bitcoin(dot)org with advertisements removed and third-party trackers disabled. I've already had the pleasure making some small contributions. btcinformation.org/en/posts/…
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Today is my tenth anniversary as a Bitcoin technical writer. In a decade of contributing, I've made amazing friendships that will last the rest of my life and learned of things more fantastical than most fiction. 1/2
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Russell Yanofsky belongs in the Bitcoin Hall of Legends. I'm looking at this week's merge of github.com/bitcoin/bitcoin/p… - 31 months from open to merge - updated or rebased 152 times - created almost a dozen spin-off PRs - almost 200 comments by all reviewers That's commitment.
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I recommend reading this: it's the most detailed and vivid description I've seen yet of how decentralized consensus systems become increasingly centralized as validation resource requirements increase and marginal peers stop fully validating and start trusting miners instead. nitter.app/StopAndDecrypt/status/…
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For those who don't know, @CobraBitcoin may co-own Bitcoin.org but he's had little to do with the production, translation, and maintenance of its content. His major contribs are allowing Google to track pageviews, reducing server security, and gratuitous pontification
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The @bitcoincoreorg download page now provides instructions to help you verify your Bitcoin Core download. bitcoincore.org/en/download/ Thanks to @kallerosenbaum for suggesting an improvement, and to PR reviewers @kallerosenbaum, @bitstein, @MarcoFalke, BlockchainBilly, & @orionwl.
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Hey @BitcoinCom and @PeterRizun, I fixed your illustration for you. Looking forward to seeing your article updated.
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How many of the people complaining about high fees on Bitcoin would be saying nice things about Bitcoin if it had low fees? Every year it's a new complaint and a new set of knockoffs claiming to fix the complaint. It's ok to worry, but don't take all your cues from serial haters.
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I'd like to thank #bcash for reducing estimated Bitcoin inflation in the next year from 4.0% to 2.4%. It's like a mini-halving.
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If you like Bitcoin and you're capable of reviewing programming logic, please consider participating in the structured review of schnorr, taproot, and tapscript described in this week's newsletter.
Bitcoin Optech newsletter #69 is here: - invites participation in a structured taproot proposal review - highlights updates to two Bitcoin wallets - requests C-Lightning & Bitcoin Core RC testing - lists changes to popular Bitcoin infrastructure projects bitcoinops.org/en/newsletter…
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The only tokens you'll regret not having bought are the ones you don't buy. #LookAtMeImNaval
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I wish I had previously said more publicly about the problems Luke causes for other contributors. Maybe then the millions he has recently received would've gone instead to the quiet, undramatic builders that really help move Bitcoin forward. I'm sorry.
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My reply to a press inquiry about Segwit2x being called off. (I like sharing these replies publicly so that it's clear I'm not trying to speak on anyone's behalf.)
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Craig Wright is a fraud.
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Today @coinbase has a valuation of $1.6 billion, or 470k BTC. Back when they were founded in June 2012, 470k BTC cost $2.4 million. #HODL
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A quickly-written reply to @balajis's article about quantifying Bitcoin's decentralization: dtrt.org/posts/minimum-major…
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I just arrived in Hawaii for a vacation. What's the first thing that happened? The Uber driver who picked me up from the airport mentioned Bitcoin, so I inquired further and found he owns BTC and is well informed about it. 1/2
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Replying to @jimmysong
1. Write 100 new or substantially improved articles for the Bitcoin Wiki, plus continue helping out elsewhere 2. Improve my cold wallet setup for (a) better security (b) easier fork selloffs (c) smoother inheritance to my family 3. Start accepting income exclusively through LN
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Read an article claiming the IRS says hardly anyone is claiming Bitcoin or other cryptocurrency capital gains. I did, but I wonder if they're not counting me because I filled in something different than what they're testing for in their free-form text field.
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Replying to @saifedean
I do think it could stick around for a while. At least until Bcash investors realize the mess their in.
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Replying to @hrdng @Excellion
Maybe we should do a trilogy or two or three.
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OTOH, I thank @SamouraiWallet for defending censorship resistance. If the most despised among us can use Bitcoin safely, then so can anyone nitter.app/alansilbert/status/904…
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All of my royalties from Mastering Bitcoin (3rd ed.) will be donated to @bitcoinbrink to support Bitcoin developers. It's impossible to write about Bitcoin technology without wanting to support the people who give it away to the world for free. dtrt.org/posts/mb3e-announce… (5/8)
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Replying to @Excellion
Why make just one movie about Bitcoin? The opportunities are endless.
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I had the pleasure of reading drafts of this book over the past several months, and I can highly recommend it to anyone who wants to acquire hands-on knowledge of the Bitcoin Protocol. Congratulations, Jimmy, and thanks for creating such a valuable educational resource!
After over a year, my book is finally out for e-devices! Print coming in 2.5-3 weeks! barnesandnoble.com/w/books/1… amzn.to/2DwvJ5R (please let them know Barnes and Noble has a better price)
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Bitmain is dumb. Many would've followed non-BIP148 chain but fewer will follow HF, so BIP148 now has higher probability of success.
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2/2 If you're enthusiastic about Bitcoin, consider contributing. You don't have to be a dev to make a difference. Find people who do work that you think is important, tell them about your skills, and ask them to suggest how you can help. Then follow through. Repeat as necessary.
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Replying to @CobraBitcoin
This isn't about PoW change for me. This is about the sum of your many and frequent complaints. You hate miners, both Bitmain and Halong; you hate hodlers; you hate the whitepaper; you hate the Bitcoin Core name; you hate tx fees---and that's just from your tweets in Feb!
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This. Consider showing respect for Nakamoto not by naming things after him but by using the name he gave to the currency he created: bitcoin.
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2/2 We had a great chat, but it's crazy and amazing that my IRL chats with random people are now basically the same as my IRC chats in #bitcoin with random people.
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Isn't that backwards? Before Bitcoin had users---and attackers---early participants fantasized about how it might work. Those who held "it in their hearts" successfully built a currency network that fulfills more and more of those early fantasies every year.
What I love about Bitcoin: the people who love it most have already abandoned it in their hearts, and spend their days fantasizing about a totally new currency network that’s nothing like it.
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Could people please stop naming things after Satoshi Nakamoto? Here's what I wrote about it in 2017:
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Replying to @hrdng @socrates1024
One year we bought her a larger monitor so we could make things easier to read. We snuck it in and installed it during a family party, hoping to surprise her. Then we asked her to check something on the computer. She never noticed the monitor swap. Still hasn't to this day.
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My full answer link and screenshot. In short: blacklisted addresses can cause payment channel users to lose money. 0bin.net/paste/nQwqU76pQ3CW0…
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This is my 2019 recommendation for anyone seeking a gentle introduction to the technical concepts behind Bitcoin. If you can use a Bitcoin wallet, I think you have enough technical background to read this book and learn about the technology that helps you keep your money safe.
Big day! Grokking Bitcoin is now available for purchase @ManningBooks! manning.com/books/grokking-b…
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TIL about @real_or_random's nifty scheme for allowing today's BTC users to upgrade to Quantum Computing (QC) resistant signatures even in the presence of fast QC attackers. Here's a quick description of it with some context for readers (& link to orig): gist.github.com/harding/bfd0…
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What I think of altcoins: fast hype-fueled peak followed by fade to obscurity. imgur.com/MX4DZLp
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Summaries of @bitcoincoreorg weekly meetings are now being published again. Get the notes from the last two meetings here: bitcoincore.org/en/meetings/ For updates, subscribe to the RSS feed here: bitcoincore.org/en/meetingrs…
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Yesterday's launch announcement for btcinformation.org was the last thing on my Twitter todo list, so I'm retiring this account and moving my microblogging to Mastodon. Hope to see you there! mastodon.social/@harding/wit…
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I am super impressed that someone on Twitter actually paid to have their hypothesis tested. My hat is off to you.
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New chapters and sections of the book cover schnorr signatures, scriptless multisignatures, MAST, P2C, taproot, tapscript, bech32(m), fee management, scriptless threshold signatures, compact block filters, compact blocks, and more. dtrt.org/posts/mb3e-announce… (2/8)
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I wrote this over two years ago. Didn't realize that @mikebelshe would try to spin easy BTC takeover as a feature. bitcoin.org/en/bitcoin-core/…
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Replying to @nopara73
Perhaps because people pay for Coinbase and Blockchain.info (the later through attention-sucking ads), but nobody pays for Bitcoin Core. Also, CB and BC.i are proprietary---so all we can do is criticize---but with Core anyone with the skills can contribute.
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Faketoshi allegedly says Bitcoin was never meant to allow key/address reuse, which agrees with the original paper---but, FYI, real Nakamoto's early code naughtily reused pubkeys when he paid Hal Finney and others. Here's the reuse code: github.com/trottier/original… Oops.
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A while ago, for the one-year anniversary of the Bitcoin Core PR Review Club (@BitcoinCorePRs), Antoine Riard collected some comments---many which mentioned @jfnewbery. The comments are public, but today I'd like to tweet some of the things people said about this amazing mentor.
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Replying to @CobraBitcoin
This is playing on reputation. Claiming to own a respected resource is to imply you played a major role in establishing that reputation. You didn't. You are, of course, entitled to publish your opinion, but I think people need to know that you're just some random blogger.
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Why are we bailing out airlines that have no demand while air-cargo shippers like UPS, Fedex, and Amazon are seeing huge spikes in demand? Please consider letting the airlines go bankrupt so that their planes, pilots, maintenance staff, etc can convert to shipping air-cargo.
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I plotted the fee rate of every confirmed tx in the past 48 hours, and those @coinbase absurd fees were weirder than I had thought.
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I'm currently updating chapter 6 and 7, which are being expanded and reorganized into four chapters with details about schnorr sigs, taproot, tapscript, modern fee bumping, and lots of other exciting new details, so there's plenty more early release content to come in the future.
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I like @LukeDashjr's idea[1] to update the new bech32 (native segwit) address format with P2SH^2 logic, although I agree with him it's possibly too late. For those who don't know about P2SH^2, I wrote a quick article.[2] [1] lists.linuxfoundation.org/pi… [2] en.bitcoin.it/wiki/P2SH%C2%B…
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Compared to my initial draft, the book has been much improved thanks to comprehensive technical reviews from @roasbeef @renepickhardt @murchandamus. Even if I had a 10,000 character tweet, I couldn't fully express how much gratitude I have for them. (4/8)
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A hastily-written response to a journalist asking about arbitrary data inclusion in the block chain. gist.github.com/harding/1c90… (I like to publish replies to journalists so that anyone who wants to criticize me can criticize what I actually said versus what might get published.)
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Excited for this! Being able to fully partition funds from the GUI for different use cases is something I really want. E.g. separate wallets for my business transactions, my personal transactions, my watch-only wallet for cold savings, and individual wallets for low-taint txes.
Merged PR from jonasschnelli: Multiwallet for the GUI github.com/bitcoin/bitcoin/p…
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Replying to @kallerosenbaum
That Bitcoin's security depends not just on cryptography and direct financial incentives but also on users who care deeply enough about Bitcoin's consensus rules that they'll automatically refuse to accept any payments that violate those rules. Details: bitcoin.org/en/bitcoin-core/…
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Shameful. Sirer knows, or should know, that Schnorr has many other benefits not described in @SDWouters's excellent article.
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I saw a blog post by @PeterRizun claiming that current LN payments below about $0.02 aren't trustless, so $50 could end up requiring trust too if fees rise. However, there are solutions; they just aren't worth bothering about (IMO) at $0.02. Details: bitcoin.stackexchange.com/a/…
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The last 100 blocks have paid 185 BTC more in fees than the previous 100 blocks, meaning up to $370k has been lost to fees so far.
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Great Reddit comment by Gregory Maxwell about @TheBlueMatt's FIBRE network: teddit.net/r/Bitcoin/comment…
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Recommended reading. Covers what's new in upcoming Bitcoin Core 0.15.0, some planned future features, and contains interesting Q&A.
Transcript: Greg Maxwell on Bitcoin Core v0.15 etc diyhpl.us/wiki/transcripts/g… #bitcoin @bitcoincoreorg
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I think maybe someone wrote my name on satoshis.place, and then someone else turned it into "sharting", a derogatory reference to Ethereum's plans to implement security-reducing sharding. To whoever did this, I approve!
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True believers in Bitcoin would've either enforced segwit on its own if they thought it was good, or rejected it if they thought it was bad.
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Here's a more detailed explanation than I could write in a tweet.
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Fancy halving block clocks are great, but have you tried: watch 'bitcoin-cli getblockchaininfo | jq "840000 - .blocks"'
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Working on my summary of v3 relay discussion for next week's @bitcoinoptech and I feel like conspiracy-theory-guy.jpg
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Something is happening with fees. These are the in-block fees from the last week; note the spike this morning. Mempool size still only 17k
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I wrote many of the posts on BitcoinCore.org (and prepared, edited, or reviewed almost all the rest), and I've always felt valued as someone who makes non-code contributions. Nice try though with the concern trolling about non-code contributions being unvalued.
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Devs are going to work on what devs want to work on, but I'd rather see work on Schnorr signature aggregation after segwit than an hard fork
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A superb post from @suhasdaftuar to bitcoin-dev describing his opposition to BIP148 in favor of safer upgrades. lists.linuxfoundation.org/pi…
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I knew fees dropped on the weekend, but I was wondering how big the effect was. Seems like it's not huge, but rather that the weekday higher fees lag into the weekend, and the weekend lower fees lag into the weekdays. Notice that Monday & Tuesday cheaper on average than Saturday
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Updates in the third edition include the evolution of Bitcoin scripting, terminology updates (h/t @murchandamus), RGB and taproot assets, much more backup and recovery info, and complete witness transaction serialization. dtrt.org/posts/mb3e-announce… (3/8)
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Finally, I have to confess that updating the book took more out of me than I expected. I don't think I could've finished if it hadn't been for the unreserved support and encouragement of my incredible partner, @33countyplates. Thank you, Amanda. I love you. (8/8)
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Replying to @jimmysong @satoshi
Note, you don't need to understand the math to protect yourself from fake celebrities. Simply demand that anybody---no matter how potentially famous---pass the same test you'd use to verify that a normal person controlled the private key corresponding to an address.
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Congrats @BRDHQ on your recent fund raise. Question, how do you know your users are storing $6 billion using your software? Last I heard you used BIP37 bloom filters, which shouldn't be sending info about user balances back to you. techristic.com/crypto-wallet… (h/t #bitcoin IRC)
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I also owe a big thanks to the inimitable @adamcjonas, who did the scariest thing possible to an educational author: introduced me to teachers such as @femilonge and @dulce_vird who will be depending on the book for their classes. Femi, Dulce: I hope it meets expectations! (7/8)
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as requested: caps of all coins (incl. BTC) relative to total crypto mkt cap
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Bitcoin is P2P electronic cash because each of its users (full node operators AKA *peers*) has equal rights with respect to the network (the ability to enforce arbitrary protocol rules), it's tracked using *electronic* databases, and is a bearer asset (*cash*).
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A gentle (but excellent) introduction to one of the most used cryptographic functions in Bitcoin.
Read "Cryptographic Hashes and Bitcoin", an excerpt from Grokking Bitcoin. bit.ly/2y2imcy #Bitcoin #blockchain @kallerosenbaum
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I'd prefer to see the spec as a series of BIPs, and I'd be more than happy to handle all of the conversion work and other necessary administrivia.
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Replying to @bitstein
I'd fund people, not particular tech. I'd make a list of 150 people I thought had made excellent contributions in the past, with no funny business since then, and give them each a no-strings-attached $1 million now plus $1 million in BTC timelocked 5 years in the future.
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I'm surprised one of your leading customer needs isn't significantly lower fees. Even for the simplest of transactions, segwit saves 40% on fees. Here's a calculator when you can play around with tx sizes to see the potential savings: bitcoinops.org/en/tools/calc…
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Replying to @hrdng @CobraBitcoin
In addition, we've debated many topics, both privately and publicly. At this point, I feel it's necessary to point out that the primary focus of your recent activities seems to be pontification, rather than making any useful contributions to the site or Bitcoin in general.
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I don't think I've ever seen this @ChaincodeLabs logo before, but now that I have, my 5+ years of receiving feedback on block chain illustrations leads me to strongly suspect that there was an embarrassingly dorky discussion at some point about which way the arrows should point.
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Replying to @ziggamon @0xB10C
Very cool! Some other things that could be checked: - Native segwit (versus P2SH-wrapped segwit, ~15% extra savings) - Compressed pubkeys (33 bytes versus 65 for uncompressed) - Exact change (~32 bytes savings) - Lower fee priority (compared to other tx's in same block)
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Replying to @CobraBitcoin
I didn't say you hadn't contributed, only that you've contributed little compared to the many others who helped build Bitcoin.org's reputation as a quality source of information about Bitcoin, a reputation you play upon by styling yourself as the domain owner.
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The reverse of "first they came for...and then they came for me" is "first I defended the rights of...and so I also defended my rights".
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I thought the *capacity increases* FAQ published in Dec 2015 was clear. bitcoin.org/en/bitcoin-core/…
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Less than two hours after launch and the site already has its first community-contributed PR fixing up some broken links in the contributor docs (which, alas, are displayed by GitHub, so not covered by our CI testing). Thanks @BlockchainBilly! github.com/achow101/btcinfor…
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I sometimes feel overwhelmed by the speed and scope of Bitcoin & LN development. That makes the scale of development of the Apollo program absolutely mind boggling to me. Kudos to all the amazing people who made it happen. #Apollo50th
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