Bitcoin for Signal: A Campaign Retrospective

In October we launched a campaign to generate support and discussion around integrating bitcoin into Signal. The response was strong. The #BitcoinForSignal hashtag picked up momentum and people shared it widely. The campaign is still live at bitcoinforsignal.org.

The Origins

The genesis of this campaign comes from a Bitcoin++ hackathon project. Cashu developers built working demos that integrated a Cashu wallet directly into Signal for both iOS and Android. When we saw what they built, we were inspired to do more with it. We came up with the idea of launching an educational campaign around the integration with simple goals: show that bitcoin is great money and can be used in a privacy-preserving way, let the Signal community know that bitcoiners love Signal, and demonstrate that Cashu is easy to build with. We feel confident we achieved those goals.

Bitcoin > MobileCoin

Signal already has a built-in payments feature using MobileCoin. The wallet is actually well designed and you can send money inline in the chat really nicely. The problem is that it hasn't gained much traction among users. Bitcoin is the most widely adopted digital currency in the world. If Signal wants payments to actually get used, it makes sense to build on what people already have.

Cashu makes this possible without sacrificing privacy. It's an open-source ecash protocol with no commercial interests. The lean codebase made it easy for devs to build a working integration in a single weekend. And because ecash tokens are unlinkable, it gives bitcoin the same privacy properties that Signal users expect from their messages.

What the Cashu devs did was rip out MobileCoin and replace it with Cashu, swapping the entire UI for bitcoin. The result is a seamless experience where you can send money in the chat and the recipient can claim the token right there in the message thread.

This is something we've actually been doing for years among Cashu users. During dinners we paste Cashu tokens in Signal to pay each other back. It works. So building this into the app properly felt like a natural evolution.

Campaign Design & Branding

Design was a major emphasis for this campaign. We believe a large part of its success came from presenting the idea elegantly and professionally.

The visual identity intentionally borrows from Signal's existing brand. We used Signal's blue as the primary color so the campaign would feel native rather than foreign. The goal was to show bitcoin belonging in Signal, not invading it.

The headline "Private Messaging Needs Private Money" distills the entire argument into five words. It frames bitcoin not as an external product being pushed onto Signal users, but as a missing piece that completes what Signal already stands for.

The blur effect behind the push notification makes the message unreadable, making privacy the literal backdrop of the experience.

The main images show the actual integration in action. We wanted users to imagine exactly what this integration would feel like. Every design decision was meant to communicate one thing: bitcoin belongs here.

Reception

The campaign was well received across the board. We were featured in CoinDesk, Yahoo, and a handful of other publications. Jack Dorsey shared it. The hashtag trended in bitcoin circles for a few days. Honestly it exceeded what we expected. We thought it might stay contained to the Cashu community but it broke out beyond that.

The criticism was mostly predictable. Some privacy advocates argued that bitcoin's transparent ledger contradicts Signal's mission, suggesting Monero or Zcash instead. We expected this. Most of them didn't realize we're not proposing on-chain bitcoin. Cashu is the privacy layer. Ecash tokens are unlinkable. We included a privacy deep dive on the site that walks through the cryptography, but that nuance doesn't always land in a tweet. So we spent time in replies pointing people to the details.

Signal hasn't responded publicly. We didn't expect them to. The goal was never to pressure them into an announcement. It was to plant a seed and show there's genuine interest. If anything comes of it, it'll be on their timeline.

What We Learned

A few things:

Presentation matters more than people admit. The same idea packaged poorly would have gone nowhere. Taking the time to make it look like it already belonged in Signal made people take it seriously.

Borrowing brand language is powerful when done respectfully. We weren't trying to trick anyone into thinking this was official. But by using Signal's colors and design patterns, we made the integration feel inevitable rather than hypothetical.

Hackathon projects can become real campaigns. The devs built something functional in a weekend. We wrapped it in a story and a visual identity. That combination of working code plus clear communication is what made this resonate.

What's Next

This campaign represents something we want to do more of: imagining what bitcoin looks like when it's integrated into mainstream tech. Meeting people where they are. Integrating bitcoin into products people already use rather than asking them to come to us.

We have a few ideas for 2026. Nothing ready to announce yet, but the approach will be the same. Find places where bitcoin fits naturally, build something that demonstrates it, and present it in a way that makes people want it.

If you want to follow along, the best place is X or Nostr. And if you're a developer interested in building with Cashu, check out our documentation.