Product Security Engineer

About Hashgraph:

Hashgraph is a fast-growing software company committed to supporting, developing and servicing Hedera, an open source, proof-of-stake platform. Hedera is EVM-compatible and has been specifically built to meet the needs of enterprise and web3 applications, which require speed, security, stability and sustainability. Hedera’s public network is governed by industry-leading organizations, spanning 11 sectors and 14 regions who oversee the development and direction of the decentralized platform.

The role:

We are hiring a Product Security Engineer to embed security into the product development lifecycle and ensure vulnerabilities are found by us before they are found by others. Hedera is an enterprise-grade distributed ledger securing billions of transactions for global developer and institutions. As the platform grows with new protocol upgrades, EVM-compatible services, cross-chain infrastructure, and cryptographic primitives, the attack surface grows with it.

This role exists to ensure that security is a first-class property of every protocol upgrade, smart contract, and node shipped to production.

• Conduct end-to-end security assessments of blockchain-based systems, from cryptographic primitive design and protocol architecture through smart contract implementation and deployed infrastructure.
• Find real vulnerabilities through hands‑on review, adversarial testing, and proof‑of‑concept exploit development, not just automated scanning.
• Design adversarial test cases and proof‑of‑concept exploits for Hedera‑native services, EVM‑compatible contracts, cross‑chain bridges, and consensus‑layer components.
• Own threat modeling and security architecture reviews across product phases.
• Define and enforce security gates before new components reach production.
• Partner directly with engineering teams to translate cryptographic and protocol‑level risks into concrete, prioritised remediation work.
• Build and improve security tooling, fuzzing infrastructure, and CI/CD security automation to scale security coverage without scaling headcount.
• Track emerging blockchain and web3 attack patterns, map them to the internal codebase, and drive proactive mitigation before threats materialise.

• Security review processes are integrated across major product development workflows, not bolted on at the end.
• Security tooling and automated checks are running inside CI/CD pipelines, reducing manual review burden.
• The vulnerability backlog is prioritised and actively shrinking through structured developer collaboration.
• Engineering teams have meaningfully improved their working knowledge of web3 attack patterns and secure coding practices.

Core capabilities:

• Hands‑on vulnerability discovery and security testing across blockchain protocols, smart contracts, nodes, and APIs.
• A track record of catching real bugs, not just running automated scans.
• Strong threat modelling and security architecture review experience applied to distributed cryptographic systems.
• Experience assessing cross‑chain protocols, threshold signature schemes, or other cryptographic systems with complex trust assumptions.
• Deep working knowledge of applied cryptography, including BLS signatures, pairing‑based schemes, polynomial commitments, and Fiat‑Shamir constructions.
• Ability to reason about cryptographic failure modes and how they show up in production systems.
• Direct experience auditing or breaking a cross‑chain bridge.
• Ability to reason through trust model tradeoffs, including state proof, multisig, and oracle attestation models, and what each means for the attack surface.

Functional expertise:

• Blockchain security and secure coding practices across EVM‑compatible and non‑EVM chains.
• Security testing tooling, including static analysis, dynamic analysis, and fuzzing.
• Experience developing custom fuzzing harnesses or security test infrastructure.
• Ability to read and audit Rust and/or Java cryptographic code.
• Understanding of memory safety, constant‑time correctness, secret handling, and security risks at JNI boundaries.

Nice to haves:

• Experience designing and operating grammar‑aware fuzzing campaigns against gRPC, JSON‑RPC, or protocol‑level endpoints.
• Experience building classifier pipelines to distinguish security signal from noise.
• Prior work on Ethereum consensus client security.
• Prior work on production threshold signature systems.
• Experience building security automation tooling.
• Experience integrating AI‑assisted workflows into security review and triage processes.