MacOS Software Engineer

Janestreet; New York (NY); On-site; USD 120,000 - 160,000; Full time

Job summary

Janestreet is seeking an experienced Software Engineer specializing in macOS development to build and maintain internal applications. The ideal candidate has significant experience in the Apple ecosystem and a strong knowledge of Swift and Objective-C.

You'll lead macOS engineering practices while collaborating with a small, dynamic team, ensuring best practices and effective tooling are in place.

This role also offers opportunities to train in other languages and platforms as part of a diverse work environment.

Qualifications

• Significant professional experience in macOS applications.
• Strong expertise in the Apple ecosystem.
• Deep understanding of macOS internals and application structuring.
• Familiarity with modern Apple development tools.

Responsibilities

• Build and maintain macOS internal applications.
• Establish CI/CD pipelines and improve development tooling.
• Provide technical guidance on macOS engineering practices.
• Collaborate with engineers and stakeholders to deliver solutions.

Skills

macOS application development

Swift programming

Objective-C knowledge

UI development with SwiftUI

CI/CD and automated builds

Effective communication

Collaboration skills

Job description

About the Position

We're looking for an experienced Software Engineer with deep macOS software experience who is also willing to work in other languages and on other platforms.

In this role, you’ll help build and maintain macOS internal applications and services used by our colleagues across the firm. Our macOS footprint is growing, and we want someone who can lead on the platform side of that work—both through hands‑on development and guiding the rest of the team around what's reasonable to build, and how to build it well. The work ranges from user-facing applications to lower-level system work and interfacing with the backend services that support it.

While macOS and Swift will be your area of focus, you won't be pigeonholed there—you’ll also receive training to work in OCaml. Much of what our team owns is cross‑platform, and you'll contribute to services and applications across a variety of languages and stacks as part of a small, collaborative team. You don't need prior experience with our internal tech; we'll help you ramp up.

Beyond hands‑on development, you'll play a key role in leveling up our team's macOS engineering practices. This includes establishing CI/CD pipelines and automated builds, improving our development tooling, and defining best practices for the platform. You'll be someone the team looks to for technical guidance on what's possible on macOS and how to accomplish it well.

Strong communication and interpersonal skills are essential, as you'll collaborate with engineers and stakeholders across the firm to understand requirements, plan work, and deliver solutions that meet a variety of business needs.

About You

• Have significant professional experience building and shipping macOS applications, and strong expertise in the Apple ecosystem
• Have a strong working knowledge of Swift, and are comfortable reading and modifying Objective‑C where it comes up
• Have a deep understanding of how macOS actually works end‑to‑end: how multi‑component applications are structured, how applications interact with the operating system, how software is packaged and delivered, and how apps behave in a managed environment
• Experienced in building and shipping user interfaces on macOS with SwiftUI, AppKit, or both
• Familiar with modern dev tooling for the Apple platform, including CI/CD, automated builds, code signing, and notarization
• You understand how managed macOS environments work in practice, or have a genuine interest in learning
• Interested in contributing outside your primary expertise—we cover a broad stack and are seeking people who enjoy picking up new languages and tools
• Have strong people skills; able to work effectively in small, collaborative teams
• Having familiarity with iOS development is a plus, as there may occasionally be opportunities to work on internal mobile apps