EigenLayer AVS Development
An Actively Validated Service borrows economic security from restaked ETH through EigenLayer instead of launching its own token and validator set. Building one is middleware engineering: the ServiceManager and registry, operator signature aggregation, the task flow, and slashing logic. We build all of it, and we run operators, so we build AVSs from both sides.
An Actively Validated Service (AVS) is any system that borrows its economic security from restaked ETH through EigenLayer instead of bootstrapping its own token and validator set. Oracles, data-availability layers, bridges, keeper networks, and co-processors all need a set of operators who put capital at stake and get slashed if they misbehave.
Before restaking, every one of them had to launch a token and recruit validators first, which is slow and dilutive. An AVS reuses the security that is already staked on Ethereum: operators opt in, the AVS defines what they must do and what gets them slashed, and the service inherits a large, honest validator set from day one. EigenLayer AVS development is the engineering that turns a service idea into that on-chain system.
Building an AVS is middleware work, not a smart-contract afterthought. You need the ServiceManager and registry contracts that track which operators are opted in and how much stake backs them, the logic that aggregates operator signatures (usually BLS) so the chain can verify a whole quorum cheaply, the task or attestation flow the service actually performs, and the slashing conditions that make dishonesty expensive.
Protofire builds these from a position of experience: we run validators and node infrastructure across proof-of-stake networks, we are a core Chainlink contributor on the oracle side, and our own work includes an actively validated service for on-chain SLAs (SlaLayer) built on the EigenLayer middleware.
An AVS is a middleware stack, not one contract
We build and operate each layer, from operator registry to slashing.
ServiceManager
Registry & quorums
Signature aggregation
Task / attestation flow
Slashing & rewards
What is EigenLayer AVS development?
An AVS is a service secured by restaked ETH rather than by its own freshly minted token. Operators who already secure Ethereum opt in to also run your service and accept extra slashing risk in exchange for extra rewards. That removes the hardest part of launching security-critical infrastructure: you no longer have to bootstrap a token, convince validators to buy and stake it, and hope the set is large enough to be safe.
Instead the service starts with access to a deep, established pool of restaked capital and honest operators. The trade-off is that the security is shared and the rules are yours to define, so most of the design work is defining what operators must do and what slashes them.
EigenLayer provides the core restaking contracts; the AVS is everything on top. That means a ServiceManager that registers operators and reads their opted-in stake from EigenLayer, registry contracts that organize operators into quorums with current stake weights, and a signature-aggregation scheme (typically BLS) so a quorum's collective attestation can be verified on-chain in a single, cheap check rather than operator by operator.
On top of that sits the service's own logic: how a task is dispatched, how operators respond, and how a response is proven correct or challenged. We build this using the standard EigenLayer middleware, which we work with directly, rather than reinventing the registry and aggregation primitives.
The point of an AVS is that misbehavior costs money, so the slashing conditions are the security model, not a detail. We design them explicitly: what constitutes an objectively slashable fault, how it is proven on-chain, how challenges and fraud proofs work where the fault is not objective, and how to avoid conditions that could slash honest operators for events outside their control.
Getting this wrong either leaves the service insecure (nothing real is at stake) or drives operators away (they can be slashed unfairly). We design from the operator's perspective because we run operators, and we harden the contracts before they reach an external audit.
What we deliver
The ServiceManager, operator and stake registries, BLS aggregation, and the task or attestation flow your service performs, built on the EigenLayer middleware and hardened before audit. If your service is an oracle, a DA layer, a bridge verifier, a keeper network, or a co-processor, we shape the middleware to it rather than forcing it into a template.
An AVS is only as reliable as the operators running it. We build the off-chain operator software (task execution, signing, monitoring) and can run operator nodes ourselves, since we already operate validators and node infrastructure across proof-of-stake networks. That means the service and the operator tooling are designed together.
The rewards distribution that pays honest operators, the monitoring that surfaces missed tasks or aggregation failures before they become slashing events, and the launch and operations support to take the AVS from testnet to a live operator set. We treat an AVS as infrastructure to run, not a contract to hand over.
Who is EigenLayer AVS development for?
Teams building security-critical infrastructure (oracles, bridges, DA layers, keeper and co-processor networks) come to us when they want the economic security of a large validator set without launching a token and recruiting one. Protocols with an existing service that currently trust a small multisig or a single operator use an AVS to decentralize that trust and make faults slashable. New networks and middleware projects use the AVS model to launch with credible security from day one rather than spending a year bootstrapping it. The common thread is a service where "who is allowed to attest, and what happens when they lie" is a real security question, which is exactly what an AVS answers, and exactly the part that is easy to get subtly and expensively wrong.
An operator, an oracle contributor, and an AVS builder
Protofire is a blockchain development company with 250+ shipped projects across 60+ networks and 95+ protocols. On restaking specifically, our public work includes an actively validated service for on-chain SLAs (SlaLayer, built on the EigenLayer middleware) and the EigenLayer middleware itself, and we approach an AVS from both sides: we run validators and node infrastructure as a managed service, and we are a core contributor to the Chainlink ecosystem on the oracle side, the two disciplines an AVS lives between.
Our broader credentials: we maintain Solhint, the Solidity linter used by 1M+ developers; we are an official Safe Guardian, and Protofire-deployed networks secure $2B+ in TVL across 120+ EVM networks. When we design the slashing and aggregation for your service, it is from the perspective of the operators who will run it, because we are one.
“An AVS inherits Ethereum's validator set through restaking, so its security comes down to the slashing conditions: what counts as a fault, and how it is proven on-chain.”
FAQ
What is an EigenLayer AVS (Actively Validated Service)?
How do you build an AVS?
What is the difference between restaking and an AVS?
What kinds of services are built as AVSs?
Can you also run the operators for our AVS?
Reviewed by Luis Medeiros, Field CTO at Protofire. Last reviewed: July 2026.