Sablier

Sablier is a decentralized finance (DeFi) protocol that enables real-time streaming of payments on the Ethereum blockchain and other EVM-compatible networks. Unlike traditional lump-sum transfers, Sablier allows a payer to lock funds in a smart contract that continuously drips tokens to a recipient at a predetermined rate per second. This creates a non-discretionary cash flow that is automated, transparent, and trust-minimized, as the streaming logic is enforced by immutable code. The protocol is permissionless and composable, meaning it can be integrated into other dApps for payroll, vesting, subscriptions, or any scenario requiring continuous value transfer.

The core mechanism is the streaming contract, a specialized smart contract that holds the total allocated amount and calculates the recipient's real-time withdrawable balance. The key parameters are the start time, stop time, and total amount, which define the payment schedule. At any moment, the recipient can claim the accrued portion of the stream, a process known as withdrawing from the cliff. This model eliminates the need for manual, periodic transactions and reduces counterparty risk, as funds are escrowed and released predictably. Sablier supports a wide range of ERC-20 tokens, making it versatile for streaming stablecoins, governance tokens, or other digital assets.

Sablier's primary use cases are in decentralized payroll for DAOs and remote teams, token vesting for employees and investors, and subscription services for SaaS or content. For example, a DAO can stream salaries to contributors by the second, providing immediate liquidity and transparency. In venture capital, token cliffs and linear vesting can be automated via Sablier streams, ensuring founders and investors adhere to agreed-upon schedules without manual administration. The protocol also enables novel applications like real-time royalties for artists or pay-per-second access to cloud resources, showcasing the flexibility of programmable money flows.

From a technical perspective, Sablier operates through a set of audited, open-source smart contracts. Users interact with the protocol via a web interface or directly through its API, which allows for integration into other platforms. The protocol employs a pull-payment architecture, where recipients initiate withdrawals, optimizing for gas efficiency. Key related concepts include vesting schedules, continuous compounding, and DeFi composability. Sablier has inspired a category of real-time finance (RTF) tools and is often compared to similar streaming payment protocols like Superfluid and Nexus Mutual's vesting module, though implementation details and supported networks may differ.

At its core, Sablier functions by creating a streaming contract on a blockchain like Ethereum. This smart contract is funded with a lump sum of tokens (e.g., DAI, USDC, or a native token) and is programmed to release them to a designated recipient at a constant, per-second rate. The sender defines the total amount, the recipient's address, and the stream's duration. Once created, the contract autonomously calculates the accrued balance—the amount the recipient can withdraw at any given moment based on elapsed time—while the remaining funds are held in escrow.

The protocol's architecture is built on a pull-payment model, which is more gas-efficient and secure than push-based systems. Instead of the contract automatically sending micro-transactions every second, the recipient must initiate a transaction to "pull" their accrued funds from the stream. This design minimizes on-chain transactions and gas costs, as the recipient can withdraw as frequently or infrequently as they choose. Key technical components include the SablierV2LockupLinear contract for streams with a set start and end date, and the SablierV2LockupDynamic contract for streams with custom, potentially cliff-based distribution schedules.

Sablier integrates with ERC-20 tokens and is fully non-custodial, meaning the protocol never holds user funds; they are secured within the immutable logic of the smart contract. Developers can interact with Sablier via its smart contract APIs or use its front-end interface. Common use cases include vesting schedules for team tokens, real-time payroll for DAO contributors, and subscription services where payment flows continuously for access. The protocol's real-time nature provides transparency, as both parties can audit the flow of funds on-chain at any moment.

Sablier is a non-custodial protocol for real-time finance (RTF) that enables continuous, on-chain value transfers using a linear streaming model. At its core, Sablier's architecture is built on smart contracts that programmatically release funds—such as ERC-20 tokens or native ETH—from a sender to a recipient over a defined period. Unlike a lump-sum payment, the recipient can claim their accrued share of the stream at any block, with the contract calculating the precise, pro-rata amount available based on elapsed time. This mechanism transforms static capital into dynamic, flowing assets.

The protocol's primary technical innovation is its linear vesting formula, executed entirely on-chain. A Sablier stream is initialized with key parameters: the startTime, stopTime, and a depositedAmount. The contract's state is updated with each new block, and the withdrawable amount for the recipient is calculated as: withdrawableAmount = (depositedAmount * (block.timestamp - startTime)) / (stopTime - startTime). This deterministic calculation ensures transparency and verifiability. The sender's funds are locked in the contract, and the unstreamed portion remains under their control until it is progressively released, making the stream cancelable by the sender at any time.

Sablier's architecture is modular and chain-agnostic, originally deployed on Ethereum and now available on multiple EVM-compatible networks like Arbitrum, Optimism, and Base. The protocol utilizes a factory contract pattern, where a central SablierV2LockupLinear factory deploys minimal proxy clones for each new stream, optimizing for gas efficiency and consistency. This design separates logic from storage and allows for seamless protocol upgrades. Key contract states include the stream's status (e.g., DEPLETED, CANCELED), the fundedAmount, and the withdrawnAmount, enabling off-chain indexers and front-ends to track streaming activity in real time.

From a security and user experience perspective, the protocol is non-custodial, meaning neither Sablier Labs nor any intermediary ever holds user funds; they are solely managed by immutable smart contracts that have undergone extensive audits. The architecture also supports composable integrations, allowing other DeFi protocols and DAO tools to embed streaming payments directly into their own smart contracts or user interfaces. For example, a DAO might use Sablier to stream grant payouts to contributors, or a lending protocol could stream interest payments to lenders, all without manual intervention.