Manual Bitcoin Transactions


For something that’s used for such banal transactions like buying drugs and sending the Jamaican bobsled team to the Olympics, cryptocurrencies such as Bitcoin are actually very impressive pieces of software. It’s a very ingenious solution to the Two Generals Problem, and the fact it made a few Bitcoin early adopters very, very rich doesn’t hurt either. [Ken Shirriff] decided to take a look at the Bitcoin protocol by creating a Bitcoin address and transferring a small amount of bitcoin to that address, manually. It’s a great look at how the Bitcoin protocol actually works, and how ingenious this protocol actually is.

[Ken]’s first task was to create a Bitcoin address. This is a 256-bit private key is the basis for the Bitcoin wallet private key (after being encoded as ASCII characters), and as the 512-bit public key (after being sent through an elliptic curve algorithm). The 512-bit public key is then hashed with SHA-256 and RIPEM 160 to generate the 160-bit public key hash and the Bitcoin address.

After creating a bitcoin address and wallet, [Ken] set out on manually creating a transaction. The idea was to buy a few cents (USD) from Coinbase and send them to his manually created address. This involved creating a transaction according to the Bitcoin spec and signing the transaction. Signing each Bitcoin transaction is the key to Bitcoin’s security, and is done with a small bit of code written in the Bitcoin scripting language.

With everything written in Python, [Ken] was ready to send his transaction off into the Bitcoin network. This was done by finding a few peers on the Bitcoin network and sending off a few packets. After a little bit of mining on the network, [Ken]’s transaction went through, confirmed by a deposit into his Bitcoin wallet.

It’s an awesome writeup and impressive achievement to manually send a few Bitcoins from one wallet to another. More impressively, [Ken] provided some amazing insight into how the Bitcoin protocol works, and how much work went into its creation.

40 thoughts on “Manual Bitcoin Transactions

  1. Isnt “How to use bitcoin” a bit outside the “hack” area? (Even if it is indepth a well-written guide on the subject). Will we start to get “How to make your first website in HTML” too? Usually I do not care if a hack is not in my sphere of interrest, but this is really the wrong path to take imho.

      1. Then perhaps the write-up by HAD should have been about the actual hack part, not just bitcoin. Someone wrote a script in to make easier to use. Take a look at the public source repositories and you find these a dime a dusin. It _may_ bet ok for lifehacks, but it is outside the realm of HAD imho. But if everyone disagrees then I will have to accept that. No need to get so agressive about it.

        All that is really said about this “hack” is “It’s an awesome writeup and impressive achievement to manually send a few Bitcoins from one wallet to another.”. Which as I said is great for bitcoin-users or people interrested in the protocol, but not an interresting hack in itself.

        If you think my opinion formed as a rahter polite question constitutes whining, then you ain’t seen nothin’ yet ;-)

        1. +1 for mh.

          On a related note, there’s been too many “if you clicked through and read, you’d have known…” type comments lately.

          I rely on the HaD author telling us the primary hack of the project, after all, thats the whole point of this site, to find interesting hacks and tell us about them.

          If HaD don’t actually tell the ‘hack’ bit, don’t get mad when people moan that it’s not a hack.

          1. The funny thing is that you don’t even have to ‘click through and read’ this one. Most of the relevant information was right there. In case you missed it, it was in italics stating that he made the transfer manually. That’s the hack right there, first paragraph, sixth line.

        2. “but it is outside the realm of HAD”

          Next time HaD is up for sale you should buy it. Then you get to make statements like this with authoritah! Your HaD will be super awesome! It will only have articles that meet a very narrow definition of hack and it will only have articles that interest EVERY reader. (it will have something new about once every other year).

          Until then can we get a “not a hack comment” button in the comments section? Please! With enough clicks the ‘not a hack comment’ button would bury comments. (OK, it’s really just a not-like button) Trolls I mean users who like “not a hack” comments could optionaly turn them back on.

          Disclaimer – This comment is not a hack

          1. But it was never meant to be with authority, I plainly put that it was in my opnion as a user – and gave my reasons. Some users disagree, others agree with parts of it. Perhaps HAD sees value in knowing what their readers will actually want to read?

          2. I doubt any project would get 100% ‘its a hack’ agreement if there were such a type of vote. The HaD authors bring us hacks, informative articles, and entertaining articles, this is all good stuff.

            Go find things you think are inspirational hacks and email them to the tips@ email address, I am told if you do this ‘include a link’ thing, they may post an article about it.

          3. Interesting reply.

            Your post slaps people for sincere criticism while adding no insight to the thread.

            Seeing this, newbie, casual, and uncertain readers will be less inclined to post opinions on what they’d like to see in a community-driven site, so the owners get correspondingly less feedback – feedback they could use could make the site better.

            Heck – it makes them less inclined to post comments of any stripe! Who would want to join a conversation trolled by immature griefers?

            I’m sure slapping people makes you feel good. Keep up the good work!

          1. @C gh

            It clearly did not. It says “manual”. Perhaps I lack the intimate knowledge of the protocol but is manually moving bitcoins from one wallet to another a problem? It does not say so in the write-up. Not knowing bitcoins well, I would think it should be a pretty basic task in a bitcoin protocol.

  2. Btw: The bob team donation was donated and organized by the DOGE-Coin community not Bitcoin. If you say else, you could say that the bob team was sponsored by US-Federal-Reserve because they print the dollar the bitcoin is transfered into.

    Exchange: Doge->Bitcoin->USD->JMD

    And handling Bitcoin as a ‘something’ completes the lack if journalism on this post.
    This is not inteded to be a hate post, but a critique on the growing conservative aftertaste on this blog that bothers me. Especially the hacking community should be more open minded, more informed and posititve to new ideas and concepts

  3. I understand a little about Bitcoins (& no, I did not read the article, not interested). So tell me this, instead of trying to earn bitcoins, why not invent my own currency (“Bytecoins”) and get filthy rich for being one of the early adopters?

    1. There’s almost a thousand Bitcoin clones with exactly that idea in mind. It’s got to the point where there’s even websites that will do the work for you now. Go to and pay a bunch of money to have a coin altered, built and distributed for you, get rich, all the good stuff. Getting anybody to adopt it is the hard bit.

  4. Back in the day, Arduino used to get all the hate on HaD. Now, for the past few years, every (rare) post mentioning bitcoin gets flamed instead. Between the negative input on Bitcoin related hacks and the Fear, Uncertainty and Doubt coming from my Family, I gave up in my pursuit to invest $1000 (or more) on $10 Bitcoins. Now that they are all over the news, my family and friends are like ‘i thought you had gone insane/on drugs, etc’ And now I feel like a retard for letting it slip through my hands, for listening to others. Perhaps this is the real reason that bitcoin has so many haters. Perhaps they just don’t like the fact that Bitcoin is on the way to The Moon (taking the scenic route), and they are stuck here on lame ol’ Earth. I have a currency in mind that hasn’t been made yet. I won’t let it be just another clone though. It must improve on the existing infrastructure, and be ready to be the Universal medium of exchange in 2040. Won’t be pre-mined, and will have features in place to protect against massive mining entities. As far as real hacks go, if anyone would like to attempt to put my beloved Bitcoin to shame, I will give you an impenetrable digital vault to take a hack at. Either you will get the prize (May bruteFORCE be with you), or you will try in vain until ‘the Heat Death of the Universe’

    1. @Jedi

      I was not hating on Bitcoin (I am pretty ambivilant on the subject) but I just do not think it [this particular piece] fit on Had it done something out of the ordinary, then perhaps. But as it stands it is very far from what _I_ think is a hack (and I then tried to air my opinion). Going by the write-up (and that is really where you need to catch my attention/interrest as a reader) It is a pretty run-of-the-mill thing, just well-writen, detailed and with some code – The picture and most of the write-up is pretty standard Bitcoin article stuff. I do not expect to see food repicies here either, despite knowing many hackers like to cook – Some things just do not fit despite being awesome in their own right :-)

      And I am sorry to hear you caved in to the pressure and missed out. Think we have all been there at some point :-(

      1. actually i missed out because i bought a scooter on eBay that was in Pennsylvania and I bought the scooter with no title and drove it halfway across PA with a printed photo of a license plate, started speeding(80mph on the shoulder of the road, but obeying all street signs like ‘do not pass’, ‘pass with care’, except for speed limit one. then i ran up on a super trooper throwing radar. should have checked the gps for police station, because apparently, he was sitting in the driveway of the ‘barracks’, didn’t pull over for some pennsylvania state troopers, high speed scooter chase ensues. adrenaline wears off, go into a hairpin turn going 60, get up with guns in my face. cops say i’m on drugs because eyes are red from hauling ass on a scooter in freezing weather. spent 6 months of my life in jail plus some Pennsylvanian stole my personal belongings including wallet and flashdrive containing bitcoin wallet. they used my normal wallet to rob my bank by creating a yahoo email address with my name, transferring my bank account into their possession. they didn’t touch my bitcoin wallet, but i had a backup and transferred what little i did have over to a new wallet for safety in case they ever figured out what wallet.dat was for, and then over to where i gambled them into oblivion. And while I was in jail i wouldn’t shut up about bitcoins and i found saturday night episodes of FreeTalkLive on the radio where I could hear bitcoin going higher and higher and up to $250 and down and then when i got out of jail and realized my bank account had been robbed i was like dammit cant buy bitcoins or that miner now. but i was also relieved that although I didn’t get to pay for my BFL order, I wouldn’t have received it anyway. can’t even move to a country because apparently, not pulling over for gun wielding maniacs chasing you in a car is a felony. come on, it was adrenaline.. fight or flight response.. at least i didn’t shoot them, because god knows they can’t aim worth a sh.. (from what i’ve seen on the news anyway) now I can’t even touch a firearm, luckily, a lightsaber is not a conventional firearm (say’s my lawyer: if you invent a lightsaber, you know what? call me and we’ll be rich) he’s rich either way, he got paid very well to not do crap for me and let me plead out instead of putting up any kind of argument in my defense. temporary insanity.. permanent insanity- nope, i guess he just thinks that i’m a crazy bastard who deserves to be a convicted felon and have all driving priveleges revoked, and spend 6 months without internet and be fined into poverty..
        the offer is still up. anyone who doesn’t believe in the security of bitcoin dare to take a crack at that .dat?

        oh and if anyone needs to test the manual version of: ” bitcoind sendfrom [label] 1F7WAVHYBK4sqSFd9CQfxm1jvLwfGPxUkr 1.33701337 ” go for it!

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.