OpBits

Inspiration

We wanted to replace expensive lawyers and trust banks with Bitcoin native code. Inspired by the Sovereignty theme of bitcoin++, we built a "Trustless Trust" where you rely on math and block height, not third-party custodians. "Trust code, not lawyers."

What it does

OpBits is a Bitcoin trust fund protocol powered by nLockTime.

Visual Dashboard: Tracks locked assets and remaining time (block height).

Trustless Mechanism: Uses pre-signed transactions that are valid only after a future date.

Hybrid Custody: Users can self-custody the pre-signed JSON files or delegate storage to OpBits.

One-Click Claim: Beneficiaries broadcast the transaction instantly when the time-lock expires.

How we built it

Core: Rust and BDK (Bitcoin Dev Kit) for wallet logic and signing.

Protocol: Pure Bitcoin L1 nLockTime (no sidechains/tokens).

Frontend: A reactive web interface for interacting with raw hex data.build with Nextjs.

What we learned

How to use bdk-cli.

What's next for OpBits Decentralized Storage: Publishing pre-signed transaction blobs to Nostr or IPFS.

Hardware Wallets: Adding HWI support for signing directly from cold storage.

Built With

• bitcoin
• nextjs