Lead Security Analyst, Third Party Security
Status
Miami, USA
Full time
Remote
Compensation is not specified
Role
Security Engineer
Description
Circle is a dynamic financial technology organization pioneering the internet of money. Our goal is to enable the seamless global transfer of value at a lower cost and with unprecedented speed. With the introduction of USDC, a blockchain-based dollar, we are revolutionizing payments and markets to drive economic progress and foster financial inclusion.
Overview:
Join a remote yet cohesive team that upholds core values such as Multistakeholder commitment, Mindfulness, Excellence-driven work ethic, and High Integrity. At Circle, employee growth and success are grounded in collaborative efforts and a diverse, flexible work environment that nurtures innovation.
Responsibilities:
As a key team member, your role involves formulating and implementing a thorough blockchain security assessment plan. You will lead security evaluations on blockchain technologies, offer risk mitigation insights to enterprise teams, and enhance Circle's blockchain assessment program.
Key Responsibilities:
- Utilize in-depth knowledge of blockchains like Ethereum, Bitcoin, Solana, etc., to conduct security assessments
- Assess threat intelligence pertaining to various blockchains and provide impact analysis
- Collaborate with blockchain engineering teams to offer security recommendations
- Spearhead the design and improvement of Circle's blockchain assessment program
- Evaluate security posture of defined third-party entities associated with Circle and track risk mitigation actions
- Mentor and guide junior team members
- Produce insightful metrics and reports
Desired Skills and Qualifications:
- Bachelor's degree in computer science, computer engineering, cybersecurity, or related field, or equivalent experience
- Proficiency in diverse blockchains like Ethereum, Bitcoin, Solana
- Competence in deciphering source code, e.g., Python, Rust
- 2+ years of experience in blockchain security and 7+ years in cybersecurity, technology, or engineering roles
- Strong communication skills to articulate security risks to both technical and non-technical audiences
- Ability to assess technical controls effectively and independently
- Background in financial services or similarly regulated sectors
- Self-motivated with an aptitude to adapt to changing environments
- Innovative problem-solver who can optimize existing processes
- Certifications such as CISSP, CTPRP, CISA, CISM are advantageous but not mandatory
Additional Information:
The position offers day-one PERM sponsorship for eligible candidates.
Circle is dedicated to fostering an inclusive financial future and offers competitive compensation packages considering various factors like experience, skills, and organizational requirements. The base pay range is $130,000-$170,000 with a 15% annual bonus target, including equity and benefits such as medical, dental, vision, and 401(k).
Circle is an equal opportunity employer, promoting diversity and does not discriminate based on various factors like race, religion, gender, sexual orientation, or disability status. Let's join forces in shaping a financial future that benefits all.
Skills Required
Circle
Website
www.circle.comCompany size
Not specified
Location
United States
Description
Not specified
Status
Ment Tech
Senior Software Engineer (Blockchain)
Mumbai, India +3
Mumbai, India +3
Full time
Remote
About MentTech
MentTech is a forward-thinking technology company dedicated to transforming how mentoring and learning are delivered in the digital age. By combining advanced tools, intelligent systems, and a human-first approach, MentTech helps individuals, teams, and organizations harness the power of mentorship to unlock potential, build skills, and achieve lasting growth.
The Role
We are seeking a Smart Contract Developer responsible for ensuring that game listings within MentTech work properly and ensuring compliance with all game store policies.
Key Responsibilities:
• Architect, implement, and deploy secure smart contracts for an on-chain Play-to-Earn GameFi ecosystem
• Lead contract design decisions with a focus on robustness, auditability, gas efficiency, and resilience to attack vectors
• Mentor/junior developers: perform code reviews, establish standards, best practices in security & testing
• Collaborate cross-functionally with game designers, backend, QA, and security teams to align smart contract features with product roadmap
Qualifications:
• 2+ years hands‐on experience developing & deploying smart contracts (Solidity / EVM or equivalent) in production environments
• Track record of writing secure contracts, familiarity with common vulnerabilities (reentrancy, integer over/underflow, front-running, flash loans, etc.)
• Experience with audits, formal verification, fuzz testing, or other advanced contract assurance methods
• Strong test suite / CI workflow skills; comfortable using tools like Hardhat, Foundry, Truffle etc.
• Solid understanding of GameFi mechanics and how on-chain economics work
Bonus Points:
• Experience on multiple EVM chains or Layer-2 / sidechains
• Knowledge of cross-chain bridges, oracles, NFTs, tokenomics design
• Contributions to open-source security tooling or prior audit reports or published code you’re proud of
Why join MentTech?
At MentTech, we cultivate a culture of flexibility, autonomy, and the freedom to make a real impact on the broader Web3 ecosystem. Experience the advantages of a fully remote working environment where your expertise and contributions are rewarded with competitive compensation tailored to your role and project influence.
Ment Tech Labs
• Employee Equity & Incentives: Unlock future growth with equity and other potential incentives.
• Entrepreneurial Culture: Join a collaborative environment where we innovate together as partners.
• Cutting-edge Innovation: Work at the forefront of gaming and blockchain.
• Key Strategic Projects: Be part of transformative initiatives that are redefining the gaming landscape.
• Remote Flexibility: Enjoy a truly flexible, fully remote work setup that supports your lifestyle.
• Talented Team: Collaborate with a team of passionate, driven, and skilled professionals.
• Community Impact: Contribute to the growth and success of the Web3 and gaming communities.
• Flexible Payment Options: Receive payments in crypto or fiat, tailored to your preference.
• Growth Opportunities: Access valuable learning experiences and development paths.
MentTech Labs, Inc. is an equal opportunities workplace that doesn’t discriminate based on race, ethnicity, gender, ancestry, national origin, religion, sex, sexual orientation, gender identity, age disability, veteran status, genetic information, marital status, or any other legally protected status.
MentTech is a forward-thinking technology company dedicated to transforming how mentoring and learning are delivered in the digital age. By combining advanced tools, intelligent systems, and a human-first approach, MentTech helps individuals, teams, and organizations harness the power of mentorship to unlock potential, build skills, and achieve lasting growth.
The Role
We are seeking a Smart Contract Developer responsible for ensuring that game listings within MentTech work properly and ensuring compliance with all game store policies.
Key Responsibilities:
• Architect, implement, and deploy secure smart contracts for an on-chain Play-to-Earn GameFi ecosystem
• Lead contract design decisions with a focus on robustness, auditability, gas efficiency, and resilience to attack vectors
• Mentor/junior developers: perform code reviews, establish standards, best practices in security & testing
• Collaborate cross-functionally with game designers, backend, QA, and security teams to align smart contract features with product roadmap
Qualifications:
• 2+ years hands‐on experience developing & deploying smart contracts (Solidity / EVM or equivalent) in production environments
• Track record of writing secure contracts, familiarity with common vulnerabilities (reentrancy, integer over/underflow, front-running, flash loans, etc.)
• Experience with audits, formal verification, fuzz testing, or other advanced contract assurance methods
• Strong test suite / CI workflow skills; comfortable using tools like Hardhat, Foundry, Truffle etc.
• Solid understanding of GameFi mechanics and how on-chain economics work
Bonus Points:
• Experience on multiple EVM chains or Layer-2 / sidechains
• Knowledge of cross-chain bridges, oracles, NFTs, tokenomics design
• Contributions to open-source security tooling or prior audit reports or published code you’re proud of
Why join MentTech?
At MentTech, we cultivate a culture of flexibility, autonomy, and the freedom to make a real impact on the broader Web3 ecosystem. Experience the advantages of a fully remote working environment where your expertise and contributions are rewarded with competitive compensation tailored to your role and project influence.
Ment Tech Labs
• Employee Equity & Incentives: Unlock future growth with equity and other potential incentives.
• Entrepreneurial Culture: Join a collaborative environment where we innovate together as partners.
• Cutting-edge Innovation: Work at the forefront of gaming and blockchain.
• Key Strategic Projects: Be part of transformative initiatives that are redefining the gaming landscape.
• Remote Flexibility: Enjoy a truly flexible, fully remote work setup that supports your lifestyle.
• Talented Team: Collaborate with a team of passionate, driven, and skilled professionals.
• Community Impact: Contribute to the growth and success of the Web3 and gaming communities.
• Flexible Payment Options: Receive payments in crypto or fiat, tailored to your preference.
• Growth Opportunities: Access valuable learning experiences and development paths.
MentTech Labs, Inc. is an equal opportunities workplace that doesn’t discriminate based on race, ethnicity, gender, ancestry, national origin, religion, sex, sexual orientation, gender identity, age disability, veteran status, genetic information, marital status, or any other legally protected status.
Payment in Crypto
Sirex
Product Manager – Portfolio Companies
Full time
Remote
Product Manager – Portfolio Companies
Sirex Portfolio Companies
Salary: $135,000 – $190,000 USD base + equity
Location: Remote-first
About the role Own product strategy and roadmap for 1–2 portfolio projects (DeFi protocols, trading platforms or RWA infrastructure).
What you’ll do
Define vision, prioritize features and write specs
Work directly with smart-contract and frontend teams
Design user flows and drive product-market fit
Run user research and iterate fast
Requirements
4+ years Product Management experience
Previous Web3/DeFi product experience mandatory
Strong technical intuition
Apply → Send CV + 1 strongest product case
Sirex Portfolio Companies
Salary: $135,000 – $190,000 USD base + equity
Location: Remote-first
About the role Own product strategy and roadmap for 1–2 portfolio projects (DeFi protocols, trading platforms or RWA infrastructure).
What you’ll do
Define vision, prioritize features and write specs
Work directly with smart-contract and frontend teams
Design user flows and drive product-market fit
Run user research and iterate fast
Requirements
4+ years Product Management experience
Previous Web3/DeFi product experience mandatory
Strong technical intuition
Apply → Send CV + 1 strongest product case
Payment in Crypto
Sirex
Frontend Engineer – Web3 Products
Full time
Remote
Frontend Engineer – Web3 Products
Sirex Portfolio Companies
Salary: $120,000 – $175,000 USD base + equity
Location: Remote-first
About the role Build beautiful, high-performance frontends for DeFi, RWA and agent platforms (Next.js + Wagmi/Viem stack).
What you’ll do
Ship trading interfaces, dashboards and wallet flows
Optimize for mobile and lightning-fast UX
Integrate with smart contracts and oracles
Work directly with design and product teams
Requirements
3+ years Next.js / React + TypeScript
Strong experience with Wagmi, Viem, RainbowKit or similar
Web3 product intuition (wallets, transactions, gas UX)
Apply → Send CV + GitHub
Sirex Portfolio Companies
Salary: $120,000 – $175,000 USD base + equity
Location: Remote-first
About the role Build beautiful, high-performance frontends for DeFi, RWA and agent platforms (Next.js + Wagmi/Viem stack).
What you’ll do
Ship trading interfaces, dashboards and wallet flows
Optimize for mobile and lightning-fast UX
Integrate with smart contracts and oracles
Work directly with design and product teams
Requirements
3+ years Next.js / React + TypeScript
Strong experience with Wagmi, Viem, RainbowKit or similar
Web3 product intuition (wallets, transactions, gas UX)
Apply → Send CV + GitHub
Payment in Crypto
Sirex
On-Chain Data Analyst
Full time
Remote
On-Chain Data Analyst
Sirex Fund + Portfolio
Salary: $110,000 – $160,000 USD base + equity
Location: Remote-first
About the role
Turn raw blockchain data into actionable investment insights and portfolio monitoring tools.
What you’ll do
Build and maintain Dune dashboards + custom indexers
Track TVL, user activity, token flows and protocol health
Create weekly investment memos and anomaly alerts
Support due diligence with on-chain forensics
Requirements
Strong SQL + Python experience
Deep knowledge of The Graph, Dune, Flipside or custom subgraphs
Previous crypto research or trading background
Apply → Send CV + 1 example Dune dashboard
Sirex Fund + Portfolio
Salary: $110,000 – $160,000 USD base + equity
Location: Remote-first
About the role
Turn raw blockchain data into actionable investment insights and portfolio monitoring tools.
What you’ll do
Build and maintain Dune dashboards + custom indexers
Track TVL, user activity, token flows and protocol health
Create weekly investment memos and anomaly alerts
Support due diligence with on-chain forensics
Requirements
Strong SQL + Python experience
Deep knowledge of The Graph, Dune, Flipside or custom subgraphs
Previous crypto research or trading background
Apply → Send CV + 1 example Dune dashboard
Payment in Crypto
Sirex
Operations Associate / Chief of Staff
Full time
Remote
Operations Associate / Chief of Staff
Sirex Fund Salary: $95,000 – $135,000 USD base + carry Location: Remote-first
About the role Be the right-hand person to partners: run fund operations, portfolio support and internal processes.
What you’ll do
Manage deal flow, data rooms and investment memos
Coordinate portfolio reporting and founder updates
Handle legal, compliance and admin tasks
Support events, LP communication and hiring
Requirements
2–4 years in VC, startup ops or consulting
Extremely organized and fast-moving
Web3/native crypto understanding is mandatory
Apply → Send CV + short note “Why you’d be a great CoS”
Sirex Fund Salary: $95,000 – $135,000 USD base + carry Location: Remote-first
About the role Be the right-hand person to partners: run fund operations, portfolio support and internal processes.
What you’ll do
Manage deal flow, data rooms and investment memos
Coordinate portfolio reporting and founder updates
Handle legal, compliance and admin tasks
Support events, LP communication and hiring
Requirements
2–4 years in VC, startup ops or consulting
Extremely organized and fast-moving
Web3/native crypto understanding is mandatory
Apply → Send CV + short note “Why you’d be a great CoS”
Payment in Crypto