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Internship Spotlight: Luis Mas Castillo ’19

What are you doing this summer? We asked rising second-year MBA students to check in from their summer internships, where they are applying the lessons of their first year at Yale SOM.

Luis Mas Castillo ’19

Internship: Twitter Inc., San Francisco, California

Hometown: Lima, Peru
Favorite Yale SOM class: Executive, Innovator, Practicum in Data Analysis
Clubs and affiliations: Technology, Marketing, General Management, D&I, Consulting, Economic Development, Soccer, AHLAS
Favorite New Haven eatery: One 6 Three
Favorite professor: Amy Wrzesniewski 
More fun facts: Everything in Twitter is bird-themed: the conference rooms, the breakout rooms, many of the tools, etc. After finishing #FlightSchool (Twitter’s first-week orientation), I discovered @terns was not short for interns, but actually, a kind of bird generally found near the sea, rivers, or wetlands.

I came to Yale SOM to pivot into a career in the tech industry. After some advice from the CDO, I realized that my expertise in statistical analysis and my previous experience working with data visualization tools could be valuable transferable skills. This proved to be true when I joined Twitter’s summer internship program and worked on the trust strategy and analytics team.

The program recruits undergrads, master’s, Ph.D., and MBA students from all around the world, and interns join many different teams under various departments. It is important to highlight that the University Recruiting team at Twitter does a great job before the internship trying to find the best fit for each intern and during the 12-week program not only following up on each intern’s progress but also organizing professional development workshops, lunch-and-learn talks with different leaders from the company, and social events both inside and outside the office to make the intern’s time in San Francisco a great experience.

My work on the trust strategy and analytics team involved analyzing policy, researching, querying and analyzing data, and creating dashboards to provide insights to other teams in the trust and Safety department. I had three main projects during the summer. For the first one, I audited the current spam and security policy, prepared an industry analysis, and delivered a document with recommendations highlighting opportunities to update the policy as well as the guidance provided in the company’s help center as part of the company’s commitment to clear and transparent communication with its users about the Twitter rules.

For my second project, I collaborated with colleagues from all teams in the trust and safety department and prepared a project requirement document for a new internal tool. After carefully reviewing each policy I met with different product managers to better understand the company’s policy enforcement process. This provided me with the necessary insights to prepare a single document that will serve as a guide for the engineering team when building the new tool.

For the third project, I worked on providing support for preparing Twitter’s 13th biannual Transparency Report. Twitter’s Transparency Report reflects the company’s commitment to providing meaningful transparency about requests received to disclose account information or remove content. As technology companies are facing much more scrutiny lately, it was also great to be at the company to witness two significant decisions: launching the Ads Transparency Center that allows anyone in the world to view ads that have been served on the platform and removing locked accounts from follower counts across profiles globally as part of Twitter’s effort to build trust and encourage healthy conversation. Leadership for business and society at its best.

Something that I would also like to highlight about my experience at Twitter is that as interns we were encouraged to talk to anybody within the company. During orientation week we had the opportunity to meet Jack Dorsey, Twitter’s CEO, and ask him any question. Throughout the summer, besides the lunch sessions with different executives (engineering lead Michael Montano, product lead Kayvon Beykpour, and legal and trust and safety leads Vijaya Gadde and Del Harvey to mention just some of them) organized by the University Recruiting Team, I also grabbed coffee with employees from many different teams, which helped me learn more about Twitter’s operations, culture, and the employee’s strong commitment to supporting the company’s efforts to contribute to the public conversation.

This summer internship gave me the opportunity to challenge myself in a completely different industry, to put in practice what I’ve learned during my first year at Yale SOM, and to develop new analytical skills. I really enjoyed my experience at Twitter headquarters in San Francisco, and I am very thankful to the colleagues I worked with for giving me the opportunity to manage my projects and get involved in greater initiatives at the company, and for providing mentorship and guidance when needed. At Twitter, you don’t only #LoveWhereYouWork but especially you get to #LoveWhoYouWorkWith.