Betswirl randomness relied on Chainlink VRF to supply verifiable gameplay inputs

Last updated Mon 19 Oct 2026

Betswirl randomness used Chainlink VRF (Verifiable Random Function) to provide gameplay inputs whose acceptance required a valid cryptographic proof. A valid response paired a random value with evidence that its generation had not been manipulated. Chainlink described the integration in its April 29, 2024 announcement about VRF v2.5. That announcement established historical use, while each deployment's version and billing arrangement remained separate questions. Current Betswirl game availability remains unconfirmed, and submission alone does not establish randomness delivery.

Bottom line: A valid randomness proof establishes input integrity, while game rules determine how that input becomes an outcome.

The Gameplay Requirement Behind a Request

A chance-based game needs an unpredictable input that its rules can turn into an outcome. Chainlink VRF's coordinator contract verifies the cryptographic proof on-chain before the game receives random values. That condition determines whether a random-number response meets the game's requirements. A number that looks random on a screen does not, by its appearance, demonstrate cryptographic verification.

Chainlink's April 29, 2024 VRF v2.5 announcement identified Betswirl as an existing user of Chainlink VRF. The announcement connected the integration with random gameplay. VRF supplied verifiable inputs; individual game rules determined what those inputs meant.

Inputs Around the Request

Chainlink VRF combined block data that was unknown when a request began with the oracle node's pre-committed private key. The generation process produced a random number and a cryptographic proof.

The oracle node supplied its cryptographic contribution; the VRF coordinator verified the proof on-chain before the consuming contract received random values.

Open full-size image

What Makes a Random Input Acceptable?

A Chainlink VRF random input meets the acceptance requirement only when its cryptographic proof is valid. The proof links the supplied value to the generation process.

Rejecting an unverified input and refunding a wager are different operations. The documented acceptance rule did not specify an automatic refund, cancellation, or replacement request. Refund handling depends on game rules; Chainlink's VRF v2.5 security guidance warns against cancelling or re-requesting randomness for the same commitment. A failure to meet the proof requirement therefore cannot, by itself, determine how a game handles an unresolved wager.

Off-Chain Computation and On-Chain Verification

Chainlink VRF used off-chain computation to generate the response and on-chain cryptography to check it.

Some blockchain-derived randomness schemes presented a different concern: miners or validators could influence outcomes by publishing favorable blocks. An opaque off-chain generator presented another limitation, because the application lacked an equivalent cryptographic check on its output. The requirement for unpredictable, verifiable gameplay input therefore concerned both the generation mechanism and on-chain verification of its proof.

The Fee Basis in VRF v2.5

Chainlink VRF v2.5 calculated its request premium as a percentage of the gas costs associated with the callback. The callback was the application-facing part of fulfillment. Its gas costs supplied the premium's calculation basis. That basis was distinct from a percentage charged on the player's stake or winnings.

The provider's fees also included gas costs for fulfilling the request. The premium therefore did not describe the entire request charge. The callback's gas demands and the payment arrangement were relevant cost inputs. The launch description supplied no universal Betswirl charge, and its provider-level pricing model did not specify every game's total transaction cost.

Who Pays for a VRF Request?

The application's billing arrangement determined who funded a request; VRF v2.5 allowed applications to pass randomness costs to end users at request time. That option could avoid requiring a team to maintain a subscription contract balance.

The launch presented this as an available application design. Betswirl's use of Chainlink VRF alone did not identify its selected payment arrangement.

LINK and Native-Token Billing

Chainlink VRF v2.5 supported payments in LINK and alternative assets, including native blockchain gas tokens. The launch description assigned a higher rate to alternative-asset payments than to LINK payments. That difference concerned the provider's payment model; it did not identify which asset a Betswirl player used for a wager.

The wager asset, the randomness billing asset, and the party funding the request were separate configuration questions. The provider's billing options described payment for generating randomness. They did not establish a game's accepted wager currencies or a compulsory player balance. A cost comparison needed to retain the selected billing asset alongside the applicable provider version.

Version Changes and the Migration Function

Chainlink VRF v2.5 introduced a migrate function for developers moving an integration to the next VRF version. The function provided an upgrade mechanism; it did not establish that every consuming application changed versions automatically.

The announcement identified Betswirl's VRF use alongside discussion of v2.5's improvements. It did not identify a completed migration for every Betswirl contract. Applying the new pricing model to a particular game required that game's integration to use the relevant version.

Randomness Delivery and Game Outcomes

Randomness delivery supplied an input to game logic. Game rules determined how that input became an outcome and what payment conditions followed. Cryptographic verification addressed the integrity of the generated input, leaving those application rules as a separate part of the gameplay arrangement.

A valid proof did not determine the payout distribution or establish that a player won. It also did not demonstrate a completed payment. To confirm game resolution, check its recorded outcome; to confirm a payout, check for payment under the game's rules.

Deployment Availability and Application Fit

Betswirl's React demo documented a UI integration for its games. That frontend integration and a fulfilled randomness request served different functions: one concerned the game interface, while the other concerned an accepted cryptographic input. Code availability did not establish that a particular live deployment remained usable.

Chance-based game integration needed unpredictable input whose generation satisfied the proof requirement. A task requiring the same output for identical inputs instead favored deterministic logic. Introducing randomness into that task would change its intended behavior.

Betswirl randomness: questions and answers