How you can help ensure BIP148 is a success

Over the last several weeks, I’ve seen a lot of people promoting BIP148/UASF on social media. Just the other day, someone announced they’d purchased numerous Raspberry Pis to run BIP148 full nodes. However, do these things really help BIP148? Not really.

At this point, probably almost everyone reading r/Bitcoin or using Twitter regularly knows about BIP148. Most of them have probably upgraded or even started their first node to support it. But what about people who don’t use these social media? Many people work hard all day at Bitcoin-unrelated jobs, and don’t want to spend the rest of their days thinking about their bitcoins. So the number one first thing everyone can do to help BIP148 is to talk to bitcoiners you know in the real world, and make sure they’re aware of and prepared for BIP148. Also consider spreading BIP148 awareness on any less popular social media you might use, such as Facebook or online poker sites.

Many people are already running a BIP148 node. But does this help? Not simply by running a node! A common misconception is that nodes are voting for BIP148, but this is not correct. Anyone can run any number of nodes, so this wouldn’t even be a good idea if it were possible. Rather, what matters is not that you’re running a node, but that you’re using it to receive transactions. This is what it means when people talk about economic nodes: nodes that people use for economic activity. So, if you use the wallet built-in to your Bitcoin Core+BIP148 node to receive your bitcoins, you’re doing your part to enforce BIP148. But if you use another wallet, you need to make sure you’ve configured it to actually use your own node. (How? It varies from wallet to wallet; if you can’t find instructions online, contact your wallet’s development team and ask!) If you use a wallet that can’t be configured to use your own node (including webwallets), be sure they’re either publicly committed to support BIP148, or withdraw your bitcoins before August.

This also means if you run more than one node, the others are not doing anything particularly useful. If you actually bought a bunch of Raspberry Pis to run nodes, not all is lost, however. You can sell or donate these to other bitcoiners who don’t have nodes yet, and help them setup and use their own BIP148 node. Even if you don’t have hardware to get rid of, you can still offer to help others who don’t have a node set one up!

Also of important note: make sure you’re actually running BIP148 for real. Early BIP148 proponents recommended simply setting a “uacomment” in your bitcoin.conf configuration file. This is not sufficient to support BIP148, and in fact leaves you just as vulnerable to attack as any other non-BIP148 node! To actually support BIP148 with your node, you must upgrade to a BIP148 build of Bitcoin Core. The best website to download this from is and you can install it just like any other update to Bitcoin Core (it will use your existing blockchain and wallet). You can verify your upgrade was successful by opening the “Help” menu, selecting “Debug window”, and checking that the “User Agent” line says exactly “/Satoshi:0.14.2/UASF-Segwit:0.3(BIP148)/”. If you use Bitcoin Knots rather than Core, it should say instead exactly “/Satoshi:0.14.2(+BIP148)/Knots:20170618/” (make sure it’s “+BIP148” and not “!BIP148” which means the opposite).

A lot of economic activity happens using exchanges. A good part of Bitcoin’s economy is offering services or goods for bitcoins, but at least as much of it is also buying and selling bitcoins for other currencies. Chances are, you’ve bought or sold bitcoins too. Contact your exchange(s) and ask them to upgrade to BIP148. If you want to strengthen your request, you can inform them that you will take your business elsewhere if they don’t. Keep asking them until they make a public statement of support. And most importantly, plan to switch to an exchange that supports BIP148 to buy any bitcoins after July — and be sure you don’t leave bitcoins on exchanges that might fail to upgrade in time.

The same also goes for merchants that accept bitcoins as payment. Make sure the people you do business with know about BIP148, and ideally publicly support it. You can also offer to patronise merchants [more] if they support BIP148. Keep in mind that many businesses don’t really accept bitcoins directly, but rather simply get fiat currency using a payment processor that accepts bitcoins. In those cases, you may need to focus on the payment processor rather than the business directly.

A final note: if we get to August and many miners are violating the new rule, there will likely be a campaign to try to get people to give up on BIP148 and downgrade to a miner-controlled network. Don’t give up. Even if there aren’t any miners, we can still move forward safely, but it may require upgrading nodes again (possibly with a change to the proof-of-work algorithm if necessary — don’t believe the FUD making this sound worse than it really is). As usual, be sure to check that trustworthy developers and/or community members have signed off on the update first. I will make a point to post on this Medium blog with advice in such circumstances. You can also follow me on Twitter for updates more often (although I post about other things on Twitter too). Be sure anyone you’ve informed/helped with BIP148 is aware of this too!

Bitcoin Core developer