Fractional Head of Security & Web3 Operations (Advisory / Retainer)

Internsg; Singapore; Remote; SGD 67,000 - 134,000; Full time

Job summary

Internsg is seeking a Singapore-based Web3 engineer or security specialist to serve as a fractional technical advisor. You will bridge leadership and external smart contract developers while enforcing institutional-grade OpSec.

This advisory role is not full-time; it offers a monthly retainer and governance responsibilities, with hands-on oversight of EVM work, security reviews, and deployment safeguards for Base/Layer-2 environments.

Qualifications

• 3–6 years in software engineering with 2+ years in Web3/security.
• Singapore-based with local presence.
• Hands-on experience with EVM, Solidity, Base/Optimism L2s.
• Operational security and incident response experience.
• Ability to translate technical risk for leadership.

Responsibilities

• Review PRs, specs, milestones and translate trade-offs for leadership.
• Implement and document multi-signature wallet architecture and procedures.
• Audit deployment pipelines, DNS, RPCs, and cloud security.
• Verify smart contract deployments, upgrades, and parameters.
• Coordinate with auditors and maintain an emergency pause playbook.

Skills

EVM Competence

Solidity

Web3 Security

Technical Translation

Tools

Safe Multi-Sig

Ledger/Trezor

Air-gapped signing

Job description

Overview

We are an established boutique investment firm running a live, yield-bearing USDC protocol on the Base network. We need a technically sharp, Singapore-based Web3 engineer or security specialist to serve as our fractional technical advisor.

Your mandate is straightforward: act as the pragmatic technical bridge between leadership and external smart contract developers, while setting up and enforcing institutional-grade operational security.

This is not a full-time build role. It is an advisory and governance post suited for a mid-to-senior blockchain developer, auditor, or security engineer who wants high-level exposure and a consistent monthly retainer alongside their primary commitments.

Key Responsibilities

• Developer Oversight & Technical Translation: Review PRs, technical specs, and milestone deliverables from external dev teams. Translate technical trade-offs into plain English for commercial leadership before sign-off.

• Key Management & Wallet Architecture: Implement, document, and maintain strict multi-signature policies (Safe) across hardware wallets, backup recovery protocols, and operational signing ceremonies.

• Operational Security (OpSec): Audit and tighten end-to-end access controls for deployment pipelines, domain registrar DNS, RPC nodes, and cloud infrastructure.

• Deployment & Verification Safeguards: Verify smart contract deployments, contract upgrades, parameter adjustments, and verify BaseScan code before transaction execution.

• Incident Response & Audit Triage: Coordinate with external smart contract auditors, triage reported vulnerabilities, and maintain a lightweight emergency pause/recovery playbook.

What We Are Looking For

• Local Presence: Based in Singapore, available for occasional in-person working sessions over coffee.

• Hands-on EVM Competence: Direct experience interacting with EVM contracts, Base/Optimism L2s, and DeFi primitives (ERC-20, vaults, liquidity pools). You understand Solidity code well enough to catch logic flaws or integration bugs.

• OpSec Pragmatism: Deep familiarity with institutional custody setups (Safe multi-sig, Ledger/Trezor, air-gapped signing, revoke permissions, RPC manipulation defenses). You focus on practical, rock-solid security rather than theoretical bureaucracy. You will remain up to speed on new threat vectors.

• Clear Communication: Ability to cut through developer jargon, assess risk clearly, and explain the commercial impact of technical decisions.

• Experience Level: 3 to 6 years in software engineering with at least 2 years focused on Web3/smart contract security. You do not need to be an ex-enterprise CSO, but you must know how production DeFi fails and how to safeguard capital.

Compensation & Engagement

• Monthly advisory retainer based on an estimated 10 to 15 hours/month, with ad-hoc project bonuses for audit reviews or contract deployment sprints.