Bitcoin Forum

Is it still possible to make a fundamental upgrade to Bitcoin, modify its blockchain data structure and give it a Turing complete virtual machine which can run smart contract like Ethereum?

Suppose a hard fork is made, how difficult is it to achieve this? Is it more difficult than building another Ethereum from scratch?

Basic smart contracts are already possible as is.


More complex smart contracts might be enabled by the likes of Simplicity:

https://bitcointalk.org/index.php?topic=2338626.0

So far it's just a concept, but it's an example of work being done on enabling more complex smart contracts on top of the Bitcoin blockchain. Note that Simplicity is explicitely not Turing complete, as allowing Turing complete scripts being run on top of blockchains is arguably a not-so-smart idea and leads to the likes of the DAO disaster and the two Parity mishaps, ie. lacks the stringency needed for immutable transactions that include a financial incentive if exploited.


A bit closer to completion is rootstock, which would run as a sidechain and aims to offer Turing complete smart contracts on a merge-mined blockchain using 2-way pegged tokens:

https://www.rsk.co/

 

Satoshi designed Bitcoin non-turing complete in purpose, because if you make money turing-complete, you open it to an endless array of greey goo areas, potential exploits that are basically unknown unknowns. This is a disaster for store of value purpose, and I wouldn't trust smart contracts as well.

Honestly im still doubting if smart contracts (as envisioned by these that support Ethereum) are even viable at any rate. It's just never going to work in practice. Better stick to the basics (Bitcoin) and keep your money safe. Some non-turing complete "smart contracts" is ok.

This would be an altcoin or a hardfork, no way.
Can you outline, what type of smart contract you think of, that needs Turing complete machine?

Smart contracts are little more than bean-counters that allow you to store name value pairs in a block-chain and pay gas for the the privilege of
doing so and I was hoping that you could pay gas to host fully fledged sites or application servers using nodes to host the service so that these sites
could never be taken down.

I have looked at contracts written in Simplicity and nothing stops the contract from steeling all the coins after a certain date
has been reached or from changing the rules and it's all about renting out space on the block and does not really offer any free
services like local storage.

Tor can host web-sites (.onions) but it's slow and you need to keep your machine running all the time so really I was hoping to
see the best of both worlds but its missing.

Please correct me if you feel my understanding here is wrong.

That would indeed be a big innovation. But completing the connection from hosting web service to blockchain isn't easy. Need a new type of network I guess.

So it looks like a side chain is more reasonable than directly expanding the bitcoin blockchain itself?

I'm not sure what you have looked at, but it sure wasn't a Simplicity smart contract since the platform is nothing but a white paper so far.



Sidechains or 2nd layer solutions. No need to meddle with the base protocol layer that is Bitcoin. Conservative approaches are key for long-term sustainability.

The only problem is, how scalable is bitcoin blockchain itself. If it's only 7 transactions/second and less than 2MB data every 10 minutes, its usefulness will be limited

Correct. All people here in the forum repeat this mantra, and from a beginners perspective this is totally ok.
I have obeserved some behavioral patterns: with limited imagination and barriers in thinking one must come to the conclusion, that bitcoin is not what you need. It somehow doesn’t meet expectations (haha). There is this disappointment about crypto that people have, who hoped to use bitcoin system to get quickly rich, without any efforts supporting the infrastructure or development. There are These core developers who shall do this job for them... Negativity all around the corner. And in disillusion they compare current crypto technologies to banking systems, and get even angry, that the fees came down to all time low, missing the point, that these are the first signs of fruitful growth extensions. Anyhow, they then look at Ethereum for scaling, because there you should have increased throughput, just to find out, it’s only real usecase is crypto kitten (and maybe some ICOs). And bitcoin cash is not performing, because the masses don‘t accept it, hence no liquidity to do great things. Really, there’s nothing in these systems for them.
What a pity for these people!

On the other side there are those, who are inspired by the technologies. Who are enthusiastic and open minded. Who understand, that there is something happening, that is changing the world, possibly upside down. Who support the community (thankyou achow  ;)). They take the challenge of understanding the limitation, breaking there head(s) on it. They start to develop solutions around it, and make the whole eco system a bit better. There are genius people thinking about increasing throughput (segwit), smart contracts (simplicity), zero knowledge proofs, decentralization and security in the system, 2nd layer applications (side chains), atomic swaps between them, and probably many, many more. Exciting time ahead!  ;D

So it is up to each individual, to stay within their limitation(s), filled with bitterness on their capacity, becoming resentful to all the exciting things happening in the crypto eco system, where they can‘t participate.
Or become part of a vibrant environment and be convinced, to make bitcoin and the world a bit better!  :)