The Opportunity: We are seeking a Senior/Staff iOS Engineer to spearhead World ID Identity Credentials. You will architect and build the foundational client-side systems that allow users to securely extract, store, and utilize identity credentials (including government-issued eIDs and ePassports) while preserving privacy through technologies such as Zero-Knowledge Proofs (ZKPs).

• Expand the breadth and depth of World ID globally by building support for Identity credentials following ICAO 9303, mDL, mDoc and other global, national and regional standards in a platform agnostic, open, secure and privacy-preserving way.
• Support real-world use cases by developing a standards-based verifiable credentials infrastructure for privacy-preserving attestations for personal information. You will lead the implementation of client-side ZKP generation, allowing users to securely and privately share proofs with relying parties.
• Build core technologies utilizing Apple's Secure Enclave, Keychain services, and CryptoKit on device and in the cloud to optimize security, privacy, and compliance (e.g., eIDAS 2.0 readiness) and collaborate on cross-platform libraries.
• Advance an open and decentralized World ID platform for empowering third-party developers to integrate World ID without relying on proprietary technologies and systems.
• As a Senior/Staff Software Engineer on the World ID team, you’ll take ownership of key software components - designing, building, debugging, scaling and maintaining them to meet high standards. You'll work closely with product managers, cryptographers, and other stakeholders to deliver impactful solutions, driving the technical roadmap for mobile credential management. You will serve as a technical expert for your domain, own and drive critical initiatives for the company, collaborate with technical leaders across the company, mentor and grow other engineers.

About You:

• You have deep experience designing and developing native iOS applications.
• You possess domain expertise in Apple's Core NFC framework and/or have experience communicating with smart cards/RFID chips (APDU commands, ICAO 9303 ePassport standards, ISO 18013-5 mDL).
• You have a strong background in mobile security and hardware integration, featuring deep, hands-on expertise with the Secure Enclave, Keychain, and biometric authentication APIs (Face ID/Touch ID).
• You are familiar with applied cryptography and have advanced experience integrating cryptographic libraries into mobile environments via Swift interop.
• You are well-versed in Liveness & Biometrics, including Presentation Attack Detection (PAD), facial matching, and secure biometric orchestration.
• You keep up with existing and emerging identity protocol and schema standards such as Verifiable Credentials, eIDAS, EUDI, SD-JWT, BBS+ and so on.
• You are comfortable developing platform-independent libraries for reuse across mobile and cloud platforms.
• Experience with generating Zero-Knowledge Proofs (ZKPs) on mobile hardware, Verifiable Credentials, or decentralized identity protocols is a massive plus.
• Colleagues consistently vouch for your ability to collaborate, mentor other engineers, and translate complex cryptographic concepts to non-technical stakeholders. You have a knack for identifying the most important tasks, relentlessly focusing on them, and driving them to completion in ambiguous environments.

By submitting your application, you consent to the processing and internal sharing of your CV within the company, in compliance with the GDPR. Pay transparency statement (for CA and NY based roles): The reasonably estimated salary for this role at TFH ranges from $221,000 - $260,000, plus a competitive long term incentive package. Actual compensation is based on factors such as the candidate's skills, qualifications, and experience. In addition, TFH offers a wide range of best in class, comprehensive and inclusive employee benefits for this role including healthcare, dental, vision, a 401(k) plan and match, life insurance, flexible time off, commuter benefits, professional development stipend and much more!