10,000 Satoshis - Justin Ep. 04 – Open Source, Grants, Fedimint, and Building Bitcoin Tools and Community in Minnesota

In this episode of 10,000 Satoshis, joeFi sits down with Justin, an open-source developer contributing to Fedimint. Together they break down what federated e-cash is, why it matters for Bitcoiners, and how it balances privacy with ease of use. Justin shares his journey from working at Microsoft to becoming a full-time Bitcoin developer supported by open-source grants, and how the Minneapolis BitDevs meetup has grown into a thriving technical community.

We also dive into Justin’s latest project—the launch of the E-Cash App—a new wallet that supports Lightning, on-chain Bitcoin, and e-cash with features like Nostr Wallet Connect and Lightning Address integration. Justin explains why he built it, how it fits into the growing Fedimint ecosystem, and where it could go from here.

Check out Justin’s work:

👉 Download the eCash App

👉 View the eCash App on GitHub

👉 Get it on Zapstore

Follow Justin at -

👉 x: @m1sterc001guy

👉 Nostr: [email protected] 

Follow joeFi -

👉 X - @im_joeFi

👉 Nostr - [email protected]

Find local meetups in Minnesota at tcBitcoin.com.