At Fern, we believe every software company should offer a world-class API. We're building the toolkit to make that possible. We enable customers like Square, ElevenLabs, Webflow, and Intercom to offer a best-in-class developer (DX) and agent experiences (AX).
Our team is primarily ex-Palantir and ex-founders, working together from our office in Williamsburg, Brooklyn. We give builders the autonomy to take ownership, the speed to move quickly, and the support to do the best work of their careers.
Why you should work here:Experience a hyper-growth startup: Join a top-decile growth company early. You'll get firsthand exposure to how a startup scales with visibility into product, engineering, design, and go-to-market. Thinking of founding a startup someday? This is the place to learn.
High trust and autonomy: You’ll have ownership over meaningful projects from day one, with the freedom to shape technical decisions and influence product direction. We trust engineers to figure out the best path forward—without micromanagement.
We move quick: Your code will ship quickly and be used by our customers within days (and sometimes hours). We prioritize shipping fast, and invest in the developer experience toolchain to make that possible.
Few meetings and bureaucracy: No bloated sprint rituals or unnecessary status updates. Just clear priorities, thoughtful async communication, and space to build.
Palantir-inspired customer obsession: Many of our engineers come from Palantir and bring the same focus on solving real customer problems. You’ll work directly with users to tackle their top developer priorities and shape the product through hands-on feedback.
As a PHP SDK Engineer at Fern, you’ll define what great looks like for modern PHP SDKs—making them idiomatic, reliable, and delightful to use. You’ll own parts of our open source compiler, shaping the core abstractions behind all generated SDKs. You’ll also stay deeply connected to the PHP community, evolving the SDK based on real-world developer feedback and emerging best practices.
Define PHP best practices. You’ll set the tone for how a modern PHP SDK should feel — readable, idiomatic, and a joy to use. We’re constantly raising the bar to make our SDKs the best in the industry. This is more than code generation; it's about crafting PHP libraries that developers trust and love.
Build out our compiler. You'll own core components of our open source compiler, defining the primitives that power every one of our SDKs. You’ll implement new capabilities like auto-pagination and server-sent events, and push the boundaries of what a generated SDK can offer.
Engage with the PHP community. You’ll stay on top of modern PHP tools and frameworks, incorporate best practices, and work directly with developers through GitHub issues and community forums to evolve the SDK based on real-world needs.
3+ years of software development
Strong communicator; comfortable solving technical problems with customers
TypeScript proficient with willingness to work across multiple languages
Deep experience with modern PHP tools, such as Composer, Guzzle, PHPStan, and Rector
Strong grasp of PHP’s evolving ecosystem — from type checking to emerging standards like Symfony and Laravel
Enthusiasm for shaping language communities, like Niels, our C# engineer who actively engages with the .NET team
Experience with OpenAPI, AsyncAPI, Protobuf, Conjure (Palantir), Smithy (AWS), Coral (Amazon)
Your personal GitHub profile is a deep green from commits and side projects
Prime office location in the heart of Williamsburg, Brooklyn
Free meals (breakfast, lunch, and dinner)
Health, dental, and vision insurance
Unlimited vacation
Flexible WFH policy
Domestic and international team offsites
Phone screen with a Fern engineer
Three interviews: one coding, one system design, one behavioral
Come onsite to meet and work with our team
Top Skills
What We Do
Input OpenAPI. Output idiomatic SDKs and beautiful API docs. Backed by YCombinator.
