Ether.fi is one of the largest crypto companies in the world, with over $10B in assets under management and a team of ~50, almost entirely technical staff. We've been profitable since day one and are focused on building real consumer financial applications.
We believe the future of finance is true on-chain banking. Our products — Stake, Liquid, and Cash — let users earn yield through DeFi strategies and spend their assets globally through our credit card program. You can view our growth publicly on Dune (https://dune.com/ether_fi/etherfi-cash)
Position overviewWe're looking for a strong engineer to join credit card transaction team in ether.fi and contribute to the success of credit card program and the risk systems that sit on top of it.
The first pillar is the transaction stack: card authorization and every decline that shouldn't have happened. You will look into what's causing the user frictions based on the declines transactions and come up with pro-active solutions to prevent them.
The second pillar is fraud and risk. Today our defense is largely reactive; you will make it proactive on both sides of the line. Build the rules, monitoring, and internal tooling, and also use them: pull the data yourself, investigate the cases, work out what the attacker actually did, and turn that into the rule that catches it next time.
You'll work closely with Product, CX, and Compliance, and directly with our card program and fraud vendors.
What you'll doImprove the card transaction experience: hunt down and eliminate the causes of declines, failed authorizations, stuck holds, and the frictions users actually hit when they spend
Make the card program better as a product; find where it breaks for real users, propose the fix, ship it
Hunt fraud and abuse patterns: card testing, cashback farming, merchant abuse, friendly fraud, trial and force-post abuse, multi-account rings
Own our fraud stack: rules, queues, and scoring logic in Sardine, plus real-time monitoring, alerting, and automated mitigation
Investigate live cases hands-on; query the transaction data, root-cause the pattern, and propose the rule or control that stops it recurring
Build internal tools, dashboards, and scripts that make our risk and CX teams dramatically more effective
Strong fundamentals in software engineering and problem solving
4+ years of professional coding experience, shipping products
Product sense; you care about the person on the other side of a declined transaction, and you'd rather fix the cause than close the ticket
Comfortable in the data, not just the codebase; strong instinct to dig into the data by querying it rather than asking someone else to
Genuine interest in adversarial problems; you find it satisfying to stare at noisy transaction data and spot the pattern that shouldn't be there, then explain why it's there
Worked at a fintech, neobank, card issuer, or issuer processor
Experience on the card issuing side, or with a card transaction processor
Knowledge of card and payment fraud mechanics: card testing, BIN attacks, friendly fraud, merchant collusion, cashback farming
Built on a fraud decisioning or transaction monitoring platform, and sat on the operational side of one
Run fraud investigations or disputes yourself, not only supported the people who do
Competitive salary, performance-based incentives, and token allocation grant
Opportunity to work on multi-billion dollar products as part of a small team
Health, dental, and vision insurance plans
Global team with opportunity for travel and working out of our 3 offices around the world
4 weeks work from anywhere
Exciting company events and team-building off-sites
Skills Required
- Strong software engineering fundamentals and problem-solving ability
- 4+ years of professional coding experience shipping products
- Product sense and customer-focused approach to resolving transaction issues
- Ability to query and analyze transaction data independently
- Interest in adversarial problems and identifying fraud patterns
- Experience at a fintech, neobank, card issuer, or issuer processor
- Experience with card issuing or card transaction processors
- Knowledge of card and payment fraud mechanics, including card testing, BIN attacks, friendly fraud, merchant collusion, and cashback farming
- Experience building or operating fraud decisioning or transaction monitoring platforms
- Experience conducting fraud investigations or disputes
What We Do
EtherFi is a decentralized non-custodial ETH staking protocol. It is the only staking protocol that allows stakers to retain control of their keys while delegating validator operations to node operators







