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backend engineer, integrations

backend engineer

Pylon

<div>About Pylon
America&rsquo;s $13T mortgage market is one of the most important financial systems in the world. It underwrites the middle class and is the mechanism through which millions of families build wealth. But while every other financial instrument has been simplified to an API call, mortgages are still assembled by hand.
We started from zero and created the first vertically integrated mortgage platform that turns origination into a single API.
Publicly traded companies and the country&rsquo;s largest originators are already building on Pylon. Revenue is compounding monthly. We&rsquo;re backed by Peter Thiel, Conversion Capital, QED, Citi, Fifth Wall, and the founders of Ramp, Blend, and Mercury.
Working at Pylon isn&rsquo;t for those seeking comfort. The people who thrive here have high agency, strong opinions, and a track record of delivering outcomes without direction. Many of us are former founders. We move quickly, challenge each other directly, and take full ownership of results. It&rsquo;s hard work, but it will be worth it.
Join us in building America&rsquo;s mortgage rails.<h2 class="jobSectionHeader">
The Team</h2>
We're looking for Back End Engineers to join our API team. We treat our GraphQL API as a product &mdash; because it is one. Multiple customers build directly on top of it, and the quality of their experience is determined by how well we design, document, and maintain it.
Mortgage is a surprisingly rich domain to model. It's path-dependent: the choices you make early in a loan constrain what's possible later. It's nonlinear: different borrower situations branch into wildly different flows. Most APIs in this space paper over that complexity. We're building one that embraces it &mdash; encoding the real shape of mortgage into a surface that's impossible to misuse and delightful to build against.<h2 class="jobSectionHeader">
Here Is What You'll Do</h2><ul><li>
Define what a mortgage is in code. Seriously. You'll work on semantic models that don't just represent mortgages as they exist today &mdash; they expand what a mortgage can be. This is product design at the API layer.</li><li>
Build toward an event-driven API. We're moving to a world where our API doesn't just respond to requests &mdash; it tells you what happened, why, and what you can do next. You'll help design and ship that future.</li><li>
Make the complex feel simple. Our API should make the mortgage process impossible to get wrong. That means thoughtful abstractions, clear documentation, and an obsessive focus on developer experience.</li><li>
Design for nonlinearity. Mortgage flows aren't linear wizards. Our future API encodes choice, branching, and path-dependence natively. You'll work on guided experiences that model real-world complexity without exposing it as chaos.</li><li>
Treat this as a product surface. You'll think about breaking changes, versioning, onboarding, and the full lifecycle of an API that real companies depend on.</li></ul><h2 class="jobSectionHeader">
Tech Stack</h2><ul><li>
TypeScript</li><li>
GraphQL (this is the product)</li><li>
NestJS</li><li>
SQL (PostgreSQL)</li><li>
Temporal.io (workflow orchestration)</li><li>
Event-driven architecture</li><li>
AI-driven development tooling and agentic infrastructure</li></ul><h2 class="jobSectionHeader">
Who Will Succeed Here</h2>
Someone who:<ul><li>
Is deeply curious</li><li>
Wants to won features from design to development to deployment to maintence</li><li>
Is willing to put the work in to solve the hardest of problems</li></ul>
Location: Palo Alto , CA Base Salary Range: $140,000/yr to $220,000/yr + Equity + Benefits
Compensation Range: $130K - $220K</div>

Backend Engineer, API

<div>About Pylon
America&rsquo;s $13T mortgage market is one of the most important financial systems in the world. It underwrites the middle class and is the mechanism through which millions of families build wealth. But while every other financial instrument has been simplified to an API call, mortgages are still assembled by hand.
We started from zero and created the first vertically integrated mortgage platform that turns origination into a single API.
Publicly traded companies and the country&rsquo;s largest originators are already building on Pylon. Revenue is compounding monthly. We&rsquo;re backed by Peter Thiel, Conversion Capital, QED, Citi, Fifth Wall, and the founders of Ramp, Blend, and Mercury.
Working at Pylon isn&rsquo;t for those seeking comfort. The people who thrive here have high agency, strong opinions, and a track record of delivering outcomes without direction. Many of us are former founders. We move quickly, challenge each other directly, and take full ownership of results. It&rsquo;s hard work, but it will be worth it.
Join us in building America&rsquo;s mortgage rails.<h2 class="jobSectionHeader">
The Team</h2>
We're looking for Back End Engineers to join our Underwriting team. This is the team that takes human judgment out of mortgage origination &mdash; and replaces it with systems that are faster, more consistent, and more accurate than any human process could be.
Mortgage underwriting today is mostly manual. Experts read guidelines, interpret rules, cross-reference documents, and make decisions that determine whether someone gets a home. We're encoding all of that into software. Nobody has fully cracked this yet. The companies that figure it out will define the next generation of lending.
The stakes are real. An incorrectly modeled rule can cost the company tens of thousands of dollars on a single loan. A well-modeled system can help us outcompete everyone in the market.<h2 class="jobSectionHeader">
Here Is What You'll Do</h2><ul><li>
Encode natural language rules into code. You'll work with DSLs and novel techniques &mdash; including AI &mdash; to translate dense regulatory guidelines into executable logic. Think of it as compiling English into a system that makes six-figure decisions.</li><li>
Work side-by-side with mortgage experts. You won't be guessing what the rules mean. You'll pair with people who've spent their careers in mortgage to understand nuance, exceptions, and the &quot;it depends&quot; that makes this domain so hard.</li><li>
Build systems where correctness is everything. This isn't a domain where &quot;close enough&quot; works. You'll design for precision, build robust test coverage, and think deeply about failure modes.</li><li>
Push into uncharted territory. We're applying AI in ways the mortgage industry hasn't seen. You'll help define what's possible &mdash; not just implement what's been done before.</li><li>
Automate complex, regulated processes. Every rule you encode is a step toward a world where mortgages are faster, cheaper, and more accessible.</li></ul><h2 class="jobSectionHeader">
Tech Stack</h2><ul><li>
TypeScript</li><li>
Custom DSLs for rule encoding</li><li>
AI/ML tooling and agentic infrastructure</li><li>
NestJS + GraphQL</li><li>
SQL (PostgreSQL)</li><li>
Temporal.io (workflow orchestration)</li></ul><h2 class="jobSectionHeader">
Who Will Succeed Here</h2>
Someone who:<ul><li>
Is deeply curious</li><li>
Wants to won features from design to development to deployment to maintence</li><li>
Is willing to put the work in to solve the hardest of problems</li></ul>
Location: Palo Alto , CA Base Salary Range: $140,000/yr to $220,000/yr + Equity + Benefits
Compensation Range: $130K - $220K</div>

Backend Engineer, Underwriting

<div>About Pylon
America&rsquo;s $13T mortgage market is one of the most important financial systems in the world. It underwrites the middle class and is the mechanism through which millions of families build wealth. But while every other financial instrument has been simplified to an API call, mortgages are still assembled by hand.
We started from zero and created the first vertically integrated mortgage platform that turns origination into a single API.
Publicly traded companies and the country&rsquo;s largest originators are already building on Pylon. Revenue is compounding monthly. We&rsquo;re backed by Peter Thiel, Conversion Capital, QED, Citi, Fifth Wall, and the founders of Ramp, Blend, and Mercury.
Working at Pylon isn&rsquo;t for those seeking comfort. The people who thrive here have high agency, strong opinions, and a track record of delivering outcomes without direction. Many of us are former founders. We move quickly, challenge each other directly, and take full ownership of results. It&rsquo;s hard work, but it will be worth it.
Join us in building America&rsquo;s mortgage rails.<h2 class="jobSectionHeader">
The Team</h2>
We're looking for Back End Engineers to join our Integrations team. This team connects Pylon to the outside world &mdash; the partners, services, and data sources that make a seamless mortgage experience possible.
We have a critical, multi-month project ahead: building out a ton of integrations. Credit bureaus, title companies, insurance providers, document services &mdash; mortgage touches everything, and we need to plug into all of it. This is a rare opportunity to work across the entire mortgage domain and understand how all the pieces fit together, fast.<h2 class="jobSectionHeader">
Here Is What You'll Do</h2><ul><li>
Build integrations across the mortgage ecosystem. You'll connect Pylon to external partners &mdash; each with their own APIs, data formats, quirks, and reliability characteristics. No two are the same.</li><li>
Work on everything. This role touches every part of the mortgage process. You'll gain a comprehensive understanding of how mortgage works &mdash; not in theory, but by building the connective tissue that makes it function.</li><li>
Own solutions from development to deploy to maintenance. You build it, you ship it, you keep it running. Integrations are only as good as their uptime, and that's your responsibility.</li><li>
Be self-directed and versatile. The integrations surface is wide. You'll need to context-switch between partners, prioritize what matters, and drive projects forward without waiting for someone to hand you the next task.</li><li>
Move fast on a high-impact project. This isn't a &quot;someday&quot; initiative. We're building these integrations now, and each one we ship unlocks new capabilities for our customers.</li></ul><h2 class="jobSectionHeader">
Tech Stack</h2><ul><li>
TypeScript</li><li>
NestJS + GraphQL</li><li>
SQL (PostgreSQL)</li><li>
Temporal.io (workflow orchestration)</li><li>
External partner APIs (REST, SOAP, file-based &mdash; the full spectrum)</li><li>
AI-driven development tooling and agentic infrastructure</li></ul><h2 class="jobSectionHeader">
Who Will Succeed Here</h2>
Someone who:<ul><li>
Is deeply curious</li><li>
Wants to won features from design to development to deployment to maintence</li><li>
Is willing to put the work in to solve the hardest of problems</li></ul>
Location: Palo Alto , CA Base Salary Range: $140,000/yr to $220,000/yr + Equity + Benefits
Compensation Range: $140K - $220K</div>

Backend Engineer, Integrations

OpenAI

<div>
 
 About The Team
 
 
 
 Our team brings OpenAI&rsquo;s most capable technology to the world through our developer platform: the OpenAI API. As the leading AI development platform, our API is used by millions of developers and the majority of enterprises around the world, and powers the majority of AI applications that you may use on a daily basis. Most recently, we&rsquo;ve released gpt-5, gpt-realtime, Responses API, Agents SDK, and many other products and features.
 
 
 
 About The Role
 
 
 
 We are looking for a software engineer to own the design of our APIs. Our API
 
 is
 
 our product, and as such we treat its design and development with care and intentionality. Every endpoint, every field name, and every enum value is a product interface that we want to design well. We are looking for engineers who not only love building APIs, but who will also sweat the details around API design and have a discerning taste for well designed API experience. You will play a major role in shaping the future roadmap of the OpenAI API &ndash; by both building and designing it.
 
 
 
 In This Role, You Will
 
 
 
 <ul>
 <li>
 Design and build products that we launch in API &ndash; extending existing endpoints, adding new endpoints, or rethinking our entire API suite.
 </li>
 <li>
 Play a major role in our API Review process &ndash; working with all other teams to ensure our APIs meet our design standard.
 </li>
 <li>
 Collaborate closely with the rest of the API team, our Developer Experience team, and our GTM team to make our APIs the best in the world.
 
 
 </li>
 </ul>
 
 You Might Thrive In This Role If You
 
 
 
 <ul>
 <li>
 Appreciate taste in API design &ndash; you believe there are well designed APIs and poorly designed APIs
 </li>
 <li>
 Can thrive and operate independently in a fast-paced environment with ambiguous requirements and goals
 </li>
 <li>
 Love building for other developers, and thrive on feedback from opinionated users
 </li>
 <li>
 Are an engineer at heart, but are willing to lean into product decisions.
 </li>
 <li>
 Think of APIs as ladders.
 
 
 </li>
 </ul>
 
 About OpenAI
 
 
 
 OpenAI is an AI research and deployment company dedicated to ensuring that general-purpose artificial intelligence benefits all of humanity. We push the boundaries of the capabilities of AI systems and seek to safely deploy them to the world through our products. AI is an extremely powerful tool that must be created with safety and human needs at its core, and to achieve our mission, we must encompass and value the many different perspectives, voices, and experiences that form the full spectrum of humanity.
 
 
 We are an equal opportunity employer, and we do not discriminate on the basis of race, religion, color, national origin, sex, sexual orientation, age, veteran status, disability, genetic information, or other applicable legally protected characteristic.
 
 
 For additional information, please see OpenAI&rsquo;s Affirmative Action and Equal Employment Opportunity Policy Statement.
 
 
 Background checks for applicants will be administered in accordance with applicable law, and qualified applicants with arrest or conviction records will be considered for employment consistent with those laws, including the San Francisco Fair Chance Ordinance, the Los Angeles County Fair Chance Ordinance for Employers, and the California Fair Chance Act, for US-based candidates. For unincorporated Los Angeles County workers: we reasonably believe that criminal history may have a direct, adverse and negative relationship with the following job duties, potentially resulting in the withdrawal of a conditional offer of employment: protect computer hardware entrusted to you from theft, loss or damage; return all computer hardware in your possession (including the data contained therein) upon termination of employment or end of assignment; and maintain the confidentiality of proprietary, confidential, and non-public information. In addition, job duties require access to secure and protected information technology systems and related data security obligations.
 
 
 To notify OpenAI that you believe this job posting is non-compliant, please submit a report through this form. No response will be provided to inquiries unrelated to job posting compliance.
 
 
 We are committed to providing reasonable accommodations to applicants with disabilities, and requests can be made via this link.
 
 
 OpenAI Global Applicant Privacy Policy
 
 
 At OpenAI, we believe artificial intelligence has the potential to help people solve immense global challenges, and we want the upside of AI to be widely shared. Join us in shaping the future of technology.
</div>

Backend Software Engineer, API Platform

Medallion

<div>
 
 About Medallion:
 
 
 
 At Medallion, we believe healthcare teams should focus on what truly matters - delivering exceptional patient care. That&rsquo;s why we&rsquo;ve built a leading provider operations platform to eliminate the administrative bottlenecks that slow healthcare organizations down. By automating licensing, credentialing, payer enrollment, and compliance monitoring, Medallion empowers healthcare operations teams to streamline their workflows, improve provider satisfaction, and accelerate revenue generation, all while ensuring superior patient outcomes.
 
 
 As one of the fastest-growing healthcare technology companies - ranked #3 on Inc. Magazine&rsquo;s 2024 Fastest-Growing Private Companies in the Pacific Region, #5 on LinkedIn's 2024 Top US Startups, a Glassdoor Best Place to Work in 2024 &amp; 2025, and featured on The Today Show - Medallion is revolutionizing provider network management. Our CEO, Derek Lo, has been named one of the Top 50 Healthcare Technology CEOs of 2024 by The Healthcare Technology Report. Backed by $130M in funding from world-class investors like Sequoia Capital, Google Ventures, Optum Ventures, Salesforce Ventures, Acrew Capital, Washington Harbour, and NFDG, we&rsquo;re on a mission to transform healthcare at scale.
 
 
 
 About the role
 
 
 
 As a Senior Software Engineer, you will work closely with senior members of the team on a variety of high-impact projects, shipping production code during your very first week, getting steady exposure to a broad set of technologies, and rapidly taking on more responsibility. Expect to achieve massive personal growth and ship features that make a meaningful impact on the healthcare system. All on a supportive and experienced team of engineers, PMs, and designers.
 
 
 This role reports to one of our Engineering Managers and base compensation for this role may land between $170,000-$215,0000. In addition to base salary, Medallion offers equity, and benefits as part of the total compensation package. Many factors are considered when determining pay including: market data, geographic location, skills, qualifications, experience, and level.
 
 
 
 What you'll do
 
 
 
 <ul>
 <li>
 Work on meaningful projects with business impact from your very first day.
 </li>
 <li>
 Scope and lead large projects, addressing ambiguity, creating plans, and ensuring technical excellence
 </li>
 <li>
 Help develop the team roadmap, balancing key technical and product tradeoffs
 </li>
 <li>
 Teach and mentor members of the engineering team, constantly modeling how great software should be developed
 </li>
 <li>
 Work within our tech stack, which includes Python and Django on the backend, and React, JavaScript, and TypeScript on the frontend
 </li>
 <li>
 Write a lot of code :)
 
 
 </li>
 </ul>
 
 Qualifications
 
 
 
 <ul>
 <li>
 Have 4+ years of experience as a software engineer
 </li>
 <li>
 Have worked in multiple functional areas &ndash; frontend, backend, platform, services, data, or cloud infrastructure.
 </li>
 <li>
 Have a strong technical foundation
 </li>
 <li>
 Care deeply about both technical success and product success
 </li>
 <li>
 Are an excellent communicator
 </li>
 <li>
 Get things done
 
 
 </li>
 </ul>
 
 You might also have an interest in:
 
 
 
 <ul>
 <li>
 Are an excellent communicator
 </li>
 <li>
 Get things done
 
 
 </li>
 </ul>
 
 We prioritize candidate safety. Please be aware that official communication will only come from @medallion.co email addresses.
 
 
 
</div>

Senior Software Engineer

Handshake

<div>
 
 About Handshake
 
 
 
 Handshake was founded on a simple belief that everyone deserves a path to a great career, regardless of where they went to school or who they know. Today, we power 25 million job seekers, 1 million+ employers, and 1,600 educational institutions.
 
 
 In 2025, we started Handshake AI and built the fastest-growing AI data business in history. We work directly with frontier AI lab researchers to create evaluations, publish benchmarks, and push the boundary of data. We&rsquo;ve grown from $0 to ~$1B run rate and pay ~$60M to over 30K individuals every month.
 
 
 
 Why Join Handshake Now
 
 
 
 <ul>
 <li>
 Shape how every career evolves in the AI economy, at global scale, with impact your friends, family and peers can see and feel
 </li>
 <li>
 Partner hand-in-hand with world-class AI labs, Fortune 500 partners and the world&rsquo;s top educational institutions
 </li>
 <li>
 Work together with engineers, scientists, operators, and more from Palantir, Meta, Scale AI, and former YC founders
 </li>
 <li>
 Build a massive, fast-growing business with billions in revenue
 
 
 </li>
 </ul>
 
 About Handshake AI
 
 
 
 Human data is the core infrastructure to AI advancement. Frontier AI labs currently improve model capabilities with various data-intensive post-training techniques. We believe that data spend for AI training will increase by 3-5x in the next few years and continue for much longer as models take on new domains. Handshake AI supports all of the frontier AI labs, working on their most complex data at the largest scale.
 
 
 
 About The Role
 
 
 
 We&rsquo;re hiring a
 
 Software Engineer
 
 to build our Reinforcement Learning Environments (RLE) platform&mdash;the interactive systems where frontier AI models learn to complete real-world work.
 
 
 This role owns meaningful components end-to-end and plays a key part in scaling systems that power model training and evaluation.
 
 
 
 Location:
 
 San Francisco, CA (in-office, 5 days/week)
 
 
 What You&rsquo;ll Do
 
 
 <ul>
 <li>
 Build and scale core components of RLE environments and infrastructure
 </li>
 <li>
 Design and implement backend systems and data pipelines
 </li>
 <li>
 Translate ambiguous product and research needs into production systems
 </li>
 <li>
 Develop modular, reusable workflow domains
 </li>
 <li>
 Improve reliability, observability, and system performance
 
 
 </li>
 </ul>
 What We&rsquo;re Looking For
 
 
 <ul>
 <li>
 2&ndash;4 years of experience in backend, distributed systems, or ML-adjacent infrastructure
 </li>
 <li>
 Strong proficiency in ReactJS and TypeScript
 </li>
 <li>
 Solid experience with relational databases (PostgreSQL) and data modeling
 </li>
 <li>
 Experience with cloud infrastructure (AWS/GCP) and CI/CD
 </li>
 <li>
 Ability to independently drive projects from design to production
 
 
 </li>
 </ul>
 Nice to Have
 
 
 <ul>
 <li>
 Experience with simulation systems or evaluation platforms
 </li>
 <li>
 Exposure to ML systems or working with research teams
 </li>
 <li>
 Experience in fast-moving, operations-heavy environments
 
 
 </li>
 </ul>
 What Success Looks Like
 
 
 <ul>
 <li>
 Owns and delivers key RLE components end-to-end
 </li>
 <li>
 Improves system scalability and developer velocity
 </li>
 <li>
 Enables faster launch of new domains with high-quality data
 
 
 </li>
 </ul>
 
 Perks
 
 
 
 Handshake delivers benefits that help you feel supported&mdash;and thrive at work and in life.
 
 
 The below benefits are for full-time US employees.
 
 
 🎯 Ownership: Equity in a fast-growing company
 
 
 💰 Financial Wellness: 401(k) match, competitive compensation, financial coaching
 
 
 🍼 Family Support: Paid parental leave, fertility benefits, parental coaching
 
 
 💝 Wellbeing: Medical, dental, and vision, mental health support, $500 wellness stipend
 
 
 📚 Growth: $2,000 learning stipend, ongoing development
 
 
 💻 Office: Commuting support, free lunch, and gym in our SF office
 
 
 🏝 Time Off: Flexible PTO, 15 holidays + 2 flex days
 
 
 🤝 Connection: Team outings &amp; referral bonuses
 
 
 Compensation Range: $157.5K - $175K
 
 
</div>

Software Engineer I, RLE

Medra

<div><div>What We're Building:
We have been quietly building the foundational layers of our Physical AI Scientist platform:<ul><li>
Physical AI that can operate scientific instruments with human-level dexterity.</li><li>
Scientific AI that can analyze results, reason about next steps, and close the loop autonomously.</li></ul>
This is an incredibly ambitious mission, but we believe that a team of ambitious people with high ownership can accomplish incredible things.
The Team:<ul><li>
We're a team of passionate, mission-driven engineers from companies like Tesla, Amazon, SpaceX, and Neuralink. We're collaborative and love moving fast, both with our product and on team trips skiing or go-karting!</li><li>
As a team, we love nerding out about engineering and robotics &mdash; plus other topics like race cars or cooking. We like learning new things and then sharing our new knowledge with each other.</li><li>
Our team is opinionated and straightforward. We don't mind intense discussions about design tradeoffs. If we have arguments or miscommunication, we resolve conflicts quickly and empathetically.</li></ul>
In this role, you will:<ul><li>
Own the architecture and implementation of full-stack systems end-to-end &mdash; writing code daily and being in the critical path on the hardest problems, not delegating them.</li><li>
Design and implement user experiences that spark joy in our customers.</li><li>
Build kick-ass internal tools to allow us to build, support and scale our robotic fleet across multiple customer deployments.</li><li>
Set the technical direction and quality bar for full-stack engineering, and make the hard tradeoff calls on design, scope, and prioritization.</li><li>
Grow a small team of talented full-stack engineers &mdash; hiring, mentoring, and unblocking them as a force multiplier alongside your own technical work.</li></ul>
Let's talk if you have:<ul><li>
Deep proficiency with Python and the ability to rapidly implement and iterate on ideas.</li><li>
Experience building interactive front-ends with React or similar.</li><li>
Experience with TypeScript.</li><li>
Understanding of programming for the web (HTML, CSS, JS, HTTP, REST).</li><li>
Significant backend system design and implementation experience.</li><li>
A track record of being the engineer your team relies on to ship the hardest things.</li><li>
Willingness to wear many hats / a flexible attitude towards responsibilities and scope.</li><li>
Ability to move fast in an environment where things are sometimes loosely defined and you may have competing priorities or deadlines.</li><li>
Passion for learning and expanding your skillset.</li><li>
Experience leading or mentoring software engineers &mdash; and a desire to keep doing that while remaining hands-on technically.</li></ul>
Nice to have:<ul><li>
Experience with database technologies like Postgres and Redis.</li><li>
Interest and experience in robotics, machine learning, or computer vision (bonus points for past experience working with hardware).</li></ul>
This position is 100% in-person, you must be able to come on-site to our San Francisco office. We offer relocation benefits for applicants who need to relocate.
What we offer:<ul><li>
An opportunity to change the way that scientific research happens</li><li>
Fast-paced, creative, and collaborative work environment</li><li>
Significant equity ownership</li><li>
401k</li><li>
Medical insurance and dental insurance</li><li>
Unlimited PTO</li><li>
Weekday dinners</li></ul>
Medra is an equal opportunity employer and prohibits discrimination and harassment of any type without regard to race, color, ancestry, national origin, religion or religious creed, mental or physical disability, medical condition, genetic information, sex (including pregnancy, childbirth, and related medical conditions), sexual orientation, gender identity, gender expression, age, marital status, military or veteran status, citizenship, or other characteristics protected by state, federal or local law or our other policies. We value diversity at Medra and welcome applications from those who are traditionally underrepresented in tech. If you like the sound of this position but are not sure if you are the perfect fit, please apply!</div></div>

Tech Lead Manager - Full Stack

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