Senior Security Engineer, Application Security at Turnkey

<h2><strong>About Us</strong></h2><p style="min-height:1.5em">Turnkey builds secure, developer-first infrastructure for private key management, making it simple to create wallets, sign transactions, and automate on-chain actions through one elegant API – without ever exposing sensitive key material.</p><p style="min-height:1.5em"><br />Our mission is to secure the open internet by making strong cryptography and key management the default. Turnkey was founded by the team behind Coinbase Custody – the world’s largest and most secure crypto custodian – whose work has helped protect over $100B in crypto across the industry.</p><p style="min-height:1.5em"><br />Turnkey's team is low-ego, high-agency, and high-autonomy with more than 100 years of combined experience in cryptography, security, and low-level systems, building reliable infrastructure used at scale. </p><h2><br /><strong>Role Overview</strong></h2><p style="min-height:1.5em">We are hiring a Senior Application Security Engineer to join Turnkey's team and help ensure our systems, pipelines, and runtime environments are secure by design and resilient at scale.</p><p style="min-height:1.5em">You'll embed directly with product and infrastructure engineering teams, shaping how security is integrated into every aspect of our architecture. This is a hands-on, builder role ideal for someone who enjoys building secure systems from the ground up.</p><p style="min-height:1.5em"></p><h2><br /><strong>What You’ll Do</strong><br /></h2><p style="min-height:1.5em">You will partner with Product and Engineering at both the design and development stage to ensure that we implement new features securely, including (but not limited to):</p><ul style="min-height:1.5em"><li><p style="min-height:1.5em">Participating in the implementation efforts</p></li><li><p style="min-height:1.5em">Doing security reviews</p></li><li><p style="min-height:1.5em">Helping with product design decisions</p></li><li><p style="min-height:1.5em">Auditing and surfacing vulnerabilities in our current products</p></li><li><p style="min-height:1.5em">Conducting threat modeling and security assessments for new features and systems, identifying risks early and shaping secure architectural decisions.</p></li><li><p style="min-height:1.5em">Developing and improving our Automated Tooling: further enhancing our automated tooling to scale our product security capabilities and find potential code problems both before and after we deploy</p></li><li><p style="min-height:1.5em">Making the safe way, the easy way: work on defining and building application guardrails so that developers can build securely by default</p></li><li><p style="min-height:1.5em">Investigating and remediating security issues, including vulnerabilities and incidents, and drive long-term improvements to prevent recurrence</p></li><li><p style="min-height:1.5em">Embedding a culture of secure development across engineering, defining practices that influence how Turnkey builds, deplo