Users

Security is the top concern for BTC bridge users, which is why we built Fiamma Bridge—a trust-minimized and hack-resistant BTC bridge designed to drastically reduce (or even eliminate) security risks for users.

When using a bridge, users primarily care about three questions:

  1. Is the BTC held in a centralized manner?

  2. Can I trustlessly bridge to another blockchain?

  3. Can I trustlessly redeem my BTC?

Below, we address each question in detail.

1. Is the BTC held in a centralized manner?

No. Fiamma Bridge adopts an ISA (Interactive Signature Aggregation) architecture.

  • User BTC is not controlled by a single address or a fixed multisig address, but by dynamic multisig addresses, significantly reducing hacking risks.

  • In traditional single-sig or fixed multisig setups, if hackers (or malicious insiders) obtain enough private keys, all bridge assets can be stolen.

  • With dynamic multisig, such attacks are 100% prevented because:

    • The user themselves is one of the signers, and the other signers (e.g., the Bridge Committee) are counter-parties.

    • For example:

      • User A’s BTC is co-controlled by User A + the Bridge Committee.

      • User B’s BTC is co-controlled by User B + the Bridge Committee.

      • No overlap exists between users’ signing groups.

    • Even if the Committee turns malicious, they cannot steal User A’s BTC without User A’s signature—a fundamental difference from traditional bridges.

  • For technical details, see: Hack-Resistant Design.

2. Can I trustlessly bridge to another blockchain?

Yes. Take bridging to Ethereum as an example:

  • Fiamma’s bridge smart contract consists of two parts:

    1. Bitcoin Light Client Contract (verifies BTC transactions).

    2. FiaBTC Contract (mints 1:1 pegged wrapped BTC, i.e., FiaBTC).

  • The mint function in FiaBTC is designed for permissionless execution—anyone can mint FiaBTC by submitting valid proof (e.g., a Merkle proof of their BTC deposit).

Implementation Roadmap:

  • Phase 1 (Initial):

    • The mint function is guarded by an Owner, who must verify and submit a valid Bitcoin transaction to mint FiaBTC.

    • Users rely on the Owner’s liveness but are protected from arbitrary minting (the Owner cannot inflate FiaBTC supply).

  • Phase 2 (Permissionless):

    • Users can self-submit Bitcoin transaction proofs to mint FiaBTC without trusting any third party.

    • This method is more secure but requires extra user effort (e.g., signing and submitting mint transactions).

  • Hybrid Approach:

    • Fiamma will combine both methods: Users can either wait for the Owner or trigger minting themselves if the Owner is unresponsive.

3. Can I trustlessly redeem BTC?

Not yet, but minimal trust is required.

  • Users currently depend on the liveness of the Operator Group (at least one Operator must be online to process withdrawals).

  • Operators are permissionless and economically incentivized:

    • Many Operators exist in the network, competing to serve users for rewards.

    • Users only need to trust that one honest Operator is online during withdrawal.

  • Future Work:

    • Fiamma is researching ways to eliminate Operator dependency entirely, enabling fully trustless redemptions. Feasibility is under evaluation.

PreviousOperatorsNextChallengers

Last updated