Matt Gwilliam

Research Scientist
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I'm a Research Scientist...

On the Content Intelligence team. My team develops Al models for applications ranging from recommendation to moderation. My work focuses on conducting cutting-edge research in areas like image understanding and multimodal generation. In my role, I'm expected to publish papers and write open source code. If the final work is consistent with the business' goals, I support its adoption in relevant products.

Making an impact

I fully own my projects while also managing my intern's work. Based on feedback from my manager and teammates, I determine
whether to keep pushing on a project, pivot, or to move on to something new. One of the projects I'm currently leading is an idea that I pitched to my manager. It focuses on advancing image representation learning, with the goal of surpassing current state-of-the-arts methods. For the first time, I feel I'm contributing at the cutting-edge of the field, and that's very exciting.

I wish more people knew that...

The people here are very friendly, and it's nice to be in an environment of healthy accountability, where we push each other to be productive. On my team, we have a weekly meeting where we give progress updates on our projects. Seeing others accomplish cool things each week motivates me to keep moving forward with my own work.

Biggest takeaway

I didn't realize how large the company was before working here. At the same time, there's a lot of effort to maintain the best parts of startup culture. Because of this, you never know who might be interested in your work, so make sure that any documentation shared across teams is clear for readers without prior context to quickly understand.

Haoyu

Machine Learning Engineer
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I'm a Machine Learning Engineer...

On the Data Trust & Safety team. My work focuses on computer vision and multi-modal machine learning, where I design and deploy machine learning models and pipelines to address a range of challenges related to platform safety. I collaborate with teams across the organization on projects like emerging risk moderation and search recommendation safety. I enjoy the blend of research and production work, developing new ideas and seeing them improve user safety.

Making an impact

I led the end-to-end development of a multi-agent visual-inspection system, which uses a 'thinking-with-images' approach to automate investigations and significantly improve efficiency for emerging risk automation. The scale of the problem and the impact of this solution was massive, resulting in a 200x efficiency gain. It was a challenging project that required a lot of creative problem-solving, and was incredibly rewarding to see it come to life and make a real difference.

I wish more people knew that...

The work here at TikTok isn't just about content. There's a tremendous amount of serious engineering and responsible Al work that goes into keeping the platform safe. While we move fast in iteration, the process is still very thoughtful and deliberate.

Biggest takeaway

At TikTok, I've learned a lot about bridging the gap between research and production, and how to balance model accuracy with efficiency at a massive scale. I've found it's important to be curious, take ownership of problems from end to end, and always look for ways to measure your impact.

Zoey Chen

Site Reliability Engineer Intern
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I'm a Site Reliability Engineer Intern...

On the Cloud Infrastructure team. My work focuses on improving the performance, reliability, and observability of internal systems. What I've appreciated the most about my role is the level of autonomy and trust I've been given. The culture here promotes ownership, encourages continuous learning, and values both impact and personal growth. I've felt empowered to lead meaningful projects, contribute ideas freely, and improve systems that make a real difference.

Making an impact

I contributed to the internal platform for real-time data search, storage, and analysis, by enhancing its Infrastructure as Code project. I automated machine status checks and deployment steps and enabled automatic Grafana deployment. These improvements will be applied for all future data center deployments, significantly reducing manual effort in configuring and deploying new clusters.

I wish more people knew that...

Interns at TikTok are given significant ownership and trusted with projects that make a direct impact. Expectations are high, but so is the support. You're surrounded by brilliant engineers who are always willing to help and share knowledge. TikTok values initiative and ownership, so take the lead in your work: stay curious, ask questions, and always look for ways to add value.

Biggest takeaway

One of the most valuable lessons I've learned is the importance of proactive communication, especially in global teams. I've learned to align with teammates early and often, even for seemingly independent tasks. I've also learned the value of task prioritization and how open discussions can lead to more efficient planning and better outcomes.

Yatin

Mobile Engineer Intern (iOS)
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I'm a Mobile Engineer Intern...

On the Global Live Foundation team. My team focuses on creating features to empower and promote small-medium businesses on TikTok Live. In my role, I support the development of iOS app code. On a typical day, I collaborate with product managers, Ul designers, and testers to design, implement, and refine features. My favorite part of my role is investigating bug tickets, which pushes me to identify root causes, implement effective solutions, and deeply understand the existing code and the different approaches taken in the codebase.

Making an impact

One of the most exciting projects I worked on was the "Setup for Client Acquisition" page, designed to identify new streamers and help them grow their audience. The page guides users through a series of goals and introduces them to the tools and scripts they can use in their livestreams. What made this project particularly exciting was being involved from the very beginning of a brand-new feature to help professional creators grow and monetize their services.

I wish more people knew that...

As an intern, you will have the opportunity to directly contribute to core features and real-world bug fixes within the production app, so it is an authentic preview of the actual day-to-day work. My work went throrough the same review process as full-time engineers, and the code I wrote shipped to millions of devices.

From debugging high-impact issues to implementing new functionality, I was fully embedded in the engineering process and responsible for delivering real business value. This experience gave me a firsthand look at the scale, quality standards, and pace of an innovative tech company.

Biggest takeaway

One of the most valuable lessons I've learned is not to write code just to get the job done, but to write code that is intentional, maintainable and thoughtfully architected. Early on, I focused on completing tasks quickly, but my mentor helped me shift my mindset to think beyond short-term implementation. Their thorough feedback on code reviews allowed me consistently get better and apply that feedback into my next push of code.