TikTok Security Software Engineer Intern, London, 2025

About the Team
FIDO stands for Fast Identity Online. It is the state-of-the-art authentication that is arguably the most secure of all currently available authentication methods. Our team's mission is to protect both internal and external users across all company applications with secure and user-friendly FIDO2 authentication. We have a variety of tech stacks, including WebAuthN server, mobile and web SDK, tools, and other components that implement FIDO2 and support its use.
There are two major initiatives in our team, mainly separated by the different types of customers we serve:
- Internal ToE(nterprise): Empower every employee as a phishing-resistant user.
- External ToC(onsumer) and ToB(usiness): Deliver a seamless and secure FIDO2 authentication experience across all company products.

Job Responsibilities
- Support as a technical expert for requirements, design and implementation of FIDO2 services and products across TikTok's suite of products.
- Assist with the design, develop and onboard FIDO2 service with all the company services, including but not limited to compute, storage, DB systems.
- Partner with Product, Operation team, Security/Legal/Compliance and other engineering teams to identify and address authentication related security issues.
- Play a critical role in influencing cross functional partners and roadmaps to continuously tighten the security posture of overall TikTok's Infrastructure.
- Technology:
- Cloud-based microservice architecture in Golang
- Highly distributed system with data centers in multiple countries
- Data pipelines and query engines
- More specifically include
- Golang, Python and other common object-oriented programming language
- MySQL, Redis, Elastic Search, Kafka
- Grafana, Hive
- Thrift RPC, Service Mesh, Consul, TLS, mTLS
- React, Vue, Angular, NodeJS or other common web framework
- Native Android and iOS client