What is it like to be an intern at Mizuho? From analysing market trends to applying his newly learnt technical skills to develop tools for the trading floor, William Jeffries, who joined our Global Markets team, gives us a glimpse into his day-to-day experience.
I wake up…
At around 5am and start my journey into London, driving to the station before catching the train into the city. The commute gives me a chance to enjoy breakfast, catch up on the overnight news and markets, and get ready for the day ahead.
The first thing I do when I get into the office…
I start by logging into Bloomberg and reading macroeconomic reports from our strategists in Japan to understand what has happened across global markets overnight. I then join the Rates and Credit morning call, where I hear different perspectives, gauge market sentiment, and set the tone for the day ahead.
My role involves…
My day involves working on a wide range of technical projects, from analysing large datasets and building machine learning models to developing user-friendly tools and applications for our trading and sales teams.
The thing I am enjoying most about my internship…
It is the level of responsibility and trust I have been given from day one. It is incredibly rewarding to work on projects that have the potential to make a genuine difference to how people do their jobs.
What I enjoy most is that many projects combine both the technical and business sides of the role, allowing me to solve real problems and create practical solutions that can be used on the trading floor.
One of the great things about Mizuho is how approachable and supportive, and generous people are with their time, no matter how senior they are. Every conversation gives me new perspectives that help improve the tools I am building and teaches me something new every day.
At university I am studying…
I am studying Engineering, which might not be the most traditional route into finance, but the analytical thinking, structured problem-solving, and technical skills I have developed have been incredibly valuable throughout my internship.
My engineering background has taught me how to break a complex problem into manageable components, identify the key micro and macro drivers, and then build and iteratively improve the models I build for the team.
The shift from university to the workplace is…
The biggest difference was the pace. Engineering often involves a more deliberate process of planning, testing and refining, whereas on the trading floor you have to expect the unexpected and respond quickly as market conditions change.
I was also surprised by how mentally demanding it can be: maintaining focus and staying composed are essential in such a fast-moving environment. However, I quickly became accustomed to this, and once I understood the dynamics of the trading floor, I found that the same technical rigour and numerical thinking I developed through engineering remained highly relevant.
Looking back at the internship…
The internship has given me first-hand exposure to financial markets and a much deeper understanding of how trading and sales teams operate. I have been able to see the entire process, from analysing market developments and generating trade ideas through to execution.
The amount you learn in such a short period of time is remarkable, and the practical, hands-on experience provides insights that simply cannot be replicated in a classroom.
The skill I have developed the most is…
This internship has strengthened my coding skills and built on the machine-learning principles I developed at university, applying them to complex financial datasets such as FX spot and cross-currency basis modelling. It has also taught me the importance of combining quantitative analysis with market context and sound judgement.
Another big takeaway is that creating a successful tool is not just about technical functionality; it is also about designing an intuitive and user-friendly experience. On a trading floor, usability can often be the difference between a tool that becomes an essential part of someone's workflow and one that never gets used.
One piece of advice to future interns...
Throw yourself into every opportunity. Be proactive, make yourself useful, and don't be afraid to showcase the skills you bring to the table. There are so many ways to add value, and the key is figuring out how your strengths can help the people around you.
At the same time, stay curious and be open to learning from everyone you meet. Whether you're speaking to someone who has just joined the firm or a very senior member of the business, people are always happy to answer questions and share their experiences.
If you combine that initiative and a willingness to learn, you will get an incredible amount out of the experience.
For William, the internship has been an opportunity to gain real-life work experience and get a clearer sense of where his career could go next. His experience reflects what Mizuho’s internship programme is designed to offer. Learn more about how you can join Mizuho's internship programme here.
