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Jane Street Highlights Summer 2026 Strategy and Product Intern Projects
Jane Street detailed the projects completed by its Summer 2026 Strategy and Product (SP) interns, who tackled initiatives spanning trading fee attribution, risk limit management, infrastructure automation, and internal tooling.
Evan Yi designed a fee expense model to allocate loan financing costs directly to trading desks and strategies.
Philip Weaver reformed the risk limit override process for special dates to prevent inadvertent expirations and reduce manual developer reviews.
Other interns automated Linux host grouping for kernel migrations, streamlined developer workflows for an AI coding agent, and enhanced reference data alerting.
Trading Financing Cost Attribution
Evan Yi developed a model to calculate and reattribute fee expenses across four types of loan arrangements back to specific trading desks and strategies. Because position financing alters strategy profitability, different allocation methodologies influence trading parameters and capital resourcing. Yi analyzed financing terms and trading desk data to evaluate tradeoffs and build consensus around allocation prototypes.
Risk Limit Overrides on Special Dates
Philip Weaver addressed maintenance issues surrounding scheduled risk limits during macroeconomic events and daylight-saving transitions. Weaver identified instances where overrides expired unnoticed and curtailed trading. He designed automated expiration reminders by appending ownership and lifecycle metadata to special-date dictionaries, while separating mechanical daylight-saving adjustments from substantive overrides to reduce manual maintenance.
Infrastructure, AI, and Data Management
Other interns led cross-functional technical initiatives across the firm. Abby Shen automated Linux platform kernel migrations by codifying host-class classification using hardware specifications and usage metrics. Andy Parker analyzed developer interactions with the AIDE Mint AI tool, introducing an upfront planning exchange in Slack to help users guide agents before execution. Emily Zhang developed an alerting framework on the Metadata team to triage late-arriving external reference data and route high-signal notifications to downstream systems.
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The following is part of a series of posts about 2026 summer intern projects—for more,
see
“What the interns have wrought, special jumbo 2026
edition”
Strategy and Product Specialists are versatile, cross-functional contributors who drive
forward firmwide initiatives. The role requires a unique combination of big-picture
thinking (“why is this valuable to the business?”) and deep analytical problem-solving.
Full-time SPs work across all areas of the firm: on trading desks, in infrastructure
groups, and with tech teams. An SP in finance might optimize our position management
infrastructure, while an SP embedded with developers might wireframe and prioritize
improvements to core firm systems or tools used by traders. Both need to understand the
business well enough to decide what’s worth building, and get into the details deeply
enough to build it right.
SP interns are embedded directly onto a team, paired with a full-time mentor, and given
real-world projects we actually care about getting done. This is work full-timers are
excited by (and would be doing themselves, if not for our interns!).
Now that the Summer 2026 internship has wrapped up, we wanted to highlight some of the
projects our interns tackled and give you a flavor of what the SP internship is all about.
Connecting financing costs to trading decisions
A trading strategy’s profitability depends on more than the prices where we buy and
sell. Financing positions - borrowing money when you’re long and securities when you’re
short - costs money, too. Jane Street enters into various kinds of loan arrangements to
facilitate our trading, and the terms of these loans can differ considerably.
Evan Yi’s project was to develop a model for the fee expense on several types of loans,
and ensure that this model allocated financing costs back to trading desks and individual
strategies. There were a lot of ways this could have worked, and no obvious “right”
answer. For example, if you allocate by gross position size, that could penalize
strategies that take large positions, even when those positions are comparatively cheap to
finance (versus a strategy that focuses on thinly-traded securities in smaller sizes).
The choice matters because different allocations will make the same trading activity look
more or less profitable. Desks use these costs to evaluate their strategies, driving
decisions as small as tweaking trading parameters and as large as resourcing between
teams.
Evan had to understand both the details of the financing arrangements and the trading
decisions they were meant to inform. He worked with teams across the firm to learn how
loan terms are structured, how our systems model and reattribute fees, and how desks
incorporate those fees into trading decisions. Then, with his proposals in hand for each
of four loan arrangements, he analyzed data to compare the effects of different modeling
choices. The last step, driving consensus on his prototypes, required judgment about the
tradeoffs at hand and leveraged the relationships he’d built with various teams throughout
the summer.
Managing our risk limits on unusual dates
Every order sent by Jane Street’s proprietary trading systems passes through a complex
series of risk checks. For example: how many open orders can the system have at once? How
large can any single order be? These automatic checks are essential for protecting the
firm if a trading system does something unexpected, since there are thousands of systems
operating at faster than human timescales.
Each system’s risk limits are set according to a schedule: one limit might apply from 9
a.m. to 11 a.m., then another later in the day. But some days are special: when there’s a
macroeconomic event such as a Fed meeting or employment report, you might expect a flurry
of interesting trading at an unusual time of day. Even daylight-saving transitions can
require schedule adjustments (since confusingly, New York and London change their clocks
on different dates!). Traders configure overrides to give their systems appropriate
latitude on these days. But over time, those overrides have become confusing and messy to
maintain.
Philip Weaver’s project was to understand the risk limit override process and propose
improvements. He interviewed traders, dug into case studies from the code, and worked with
a team of developers to understand how date-driven limits were built. He got his hands
dirty, comparing historical limits with usage data for various systems.
His analysis led to two proposals. First, Philip found cases where limit overrides expired
unnoticed, curtailing trading at important moments. By attaching ownership and lifecycle
information to the shared dictionary where special dates are stored, he was able to lay
out an automated system of expiry reminders. In this way, the code itself could help
ensure system owners were prompted to review and extend overrides.
Second, with those tricky daylight-saving transitions, Philip split out mechanical limit
overrides in the data from the more substantive ones, proposing different review cycles
for each to reduce manual developer work and keep his new review notifications high signal
and actionable.
Getting this right required understanding why traders needed the exceptions, how the
software applied them, and how colleagues would maintain them going forward.
And more…
We had too many exciting projects to cover in depth, but a few more we wanted to quickly
mention:
Abby Shen worked with the Linux Platform team to help automate fleet-wide upgrades,
particularly kernel migrations. In her research, Abby found that the process of defining
host-classes for big migrations involved lots of manual work. Abby helped codify the
principles behind that manual process, so that hosts are instead grouped and sorted
based on a mix of hardware specs and usage metrics.
Andy Parker worked with the AI Assistants team, studying how people at Jane Street
interact with our AI tools. His interviews and analysis of session-level metadata turned
up some key frictions. Andy focused on AIDE Mint, a popular tool among developers that
turns a Slack conversation into a task for an AI agent to complete asynchronously. While
users loved how quickly they could start an agent, their code changes didn’t
consistently make it into production. Digging into why, he learned the agent too often
needed more direction before beginning work, and redirecting it wasn’t ergonomic. He
designed a lightweight exchange that lets users shape the agent’s plan in Slack before
it starts, and worked with developers to ship it.
Emily Zhang worked on the Metadata team, which stores and disseminates crucial external
reference data for trading (for example, new listings from exchanges or corporate
actions like stock splits). She dove into the data ingestion process and created an
alerting framework for cases when vendor data arrives late. Many teams and systems
downstream rely on this data. By understanding which alerts were most critical to users
and analyzing historical logs to find patterns, Emily designed a system that makes it
easier to triage the large number of issues and surface the highest signal alerts to the
appropriate consumers.
Looking forward to next summer…
This is just a sample of the shapes of projects our Strategy and Product interns worked
on this Summer. If these projects sound interesting to you, consider applying! You can
find more details about the role here:
https://www.janestreet.com/join-jane-street/sp/
. Applications
for our 2027 Summer internship are now open!