Are you sure? The protocol described in Chuck Norris book Applied Cryptography seems to work fine without a randomness beacon. Once you get the commitments from all parties they reveal the nonces and everyone verifies they match the commitments and extracts the same random bits.
In a standard 2-party commit-reveal, one party always learns the result first. (Mostly servers in current setups).
By adding a Randomness Beacon (Drand) as a third entropy source, we solve two things: No Last-Look: Neither the player nor the server knows the outcome until a specific future timestamp (the Drand round). Forced Resolution: Since the Drand signature is public, once that round passes, the result is 'locked' by math. The server can't hold the result hostage because anyone can pull the Drand signature and verify the result themselves.
I looked at VDFs and custom MPCs, but they felt like overkill for a dice roll. Drand is basically a "pre-computed" MPC that anyone can verify with a simple curl. It hits that pragmatic sweet spot for a trustless audit without the "math homework" for the user...
It turns the server from a "Judge" into a "Timestamped Vault" that can't hold the outcome hostage if it's unfavourable, giving the player a winning ticket they can verify independently.
For those interested in how a "Time-Lock" UX performs with a technical audience, here are the final numbers:
Total Reach: 370 hit the commit endpoint (Dice Roll).
The 10s Retention: Despite the mandatory 10-second wait for Drand entropy, we saw a 90% completion rate (333 revealed vs 37 abandoned). This suggests that for verifiable randomness, users are remarkably willing to trade instant gratification for proof. The abandoned commits are in read-to-reveal state in our database, can be revealed anytime.
Fairness Audit: A frequency test on the last character of the hex-randomness across all 333 rolls showed a healthy distribution (range of 13–29 hits per char), confirming no architectural bias during the surge.
If you’re interested in implementing trustless randomness for your own project—whether it’s for NFT minting, on-chain gaming, online casino, giveaway selection, or cryptographic auditing, you can reach me at rishi@blockrand.net or dive directly via the [https://github.com/blockrand-api/blockrand-js].
I’ll be hanging around the thread for a bit longer if anyone has more questions about the Drand integration!
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Commitment already pending for Round 26020619. Please wait for settlement before starting a new round.The logic of back end api (written in go, commitment stored in firestore), is intact, the 409 will come only if the same user tries to commit again before the reveal, this is by design.
If a server sees the Drand beacon just a few milliseconds before the user's commit is finalized, they can 'veto' a winning roll by dropping the packet.
Is 10s of UX friction a fair price for a Time-Lock that ensures the result literally doesn't exist anywhere in the world at the moment of commitment?
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