Backend Developer Intern Jobs in California (NOW HIRING)

About Moon
An ambitious and independent stealth SaaS company incubated by Home Organizers, a market leader with decades of proven success in designing and delivering exceptional, innovative home organization solutions through its subsidiaries Closet World, Closets by Design, Brio Water Technology, and others. Backed by their deep industry experience and a commitment to be Home Organizer's critical SaaS provider for its 6000+ employees, our team is building innovative solutions to solve universal problems that most businesses face - yet are not addressed by a single, unified tool.
Our mission is to transform the entrepreneurial experience and deliver operational excellence for businesses across the world through a unified platform supercharged with proprietary AI agents. We want to unleash the creativity of billions and inspire the world to dream big and build fast. We're a rapidly growing team of forward-thinking and, most importantly, committed builders. We are driven by the opportunity to push boundaries, reimagine the foundations of human work, and shape tools that power the next generation of "business operations." The way the world views and does business is changing, and we are committed to leading this change responsibly.
Role Overview
Our backend is a .NET Web API (C#) that powers scheduling, dispatch, billing, and reporting for home services companies. It's a production system with real load, real customers, and real consequences when something breaks. This isn't a "build a sample CRUD app and present at the end" internship - you'll be assigned real features and real technical debt from week one.
Six to twelve months is enough time to own something meaningful. You'll design API contracts, write business logic, push to staging, and ship to production - with engineers who will review your code seriously and expect you to review theirs. The mentorship is structured; the work is real.
About the role
You'll join the engineering team and be assigned a dedicated mentor with weekly 1:1s, live code
review sessions, and structured ramp milestone to achieve.
The PR bar is the same bar applied to full-time engineers. Mentorship is how we support you in
meeting it - not a reason to lower expectations.
Ideally, you'll operate 3 days on-site in Glendale, with flexibility around your academic schedule.
You'll get exposure across the full stack: .NET API, React/Capacitor frontend, Python data
pipelines, and cloud infrastructure.
AI-assisted development is the default here. Engineers use Cursor, Copilot, and Claude as primary tools - you're expected to come in already working that way.
What you'll do
API Design & Feature Delivery
Design and implement .NET Web API endpoints: contract design, business logic, data layer, and
production deployment.
Implement service-layer logic for core home services workflows - domain-heavy problems
where understanding business rules is as important as writing clean code.
Participate in API design discussions: versioning, validation, and error handling standards.
Build and test integrations between backend services and third-party APIs.
Contribute to technical design discussions - your perspective as someone newer to the
codebase is genuinely useful.
Performance, Quality Engineering Standards
Investigate and improve slow queries and high-traffic endpoints: read execution plans, write
indexes, and measure before and after.
Write unit and integration tests for everything you ship; nothing merges without adequate
coverage.
Use AI tools (Cursor, Copilot, Claude) as part of your standard workflow - code generation,
refactoring, test writing, navigating unfamiliar parts of the codebase. AI-assisted development is
your default mode, not an occasional tool.
Give and receive code review feedback from day one.
Qualifications
Required
C# coursework or project experience, or a strong background in another statically typed language
(Java, Kotlin, Go, Swift) - we'll teach you .NET specifics, but you need to understand types,
objects, and how compiled languages think.
REST API design fundamentals: HTTP verbs, status codes, request/response shapes, and what
makes an API painful vs. clean to consume.
SQL - joins, filters, aggregations, and some intuition for why a query might be slow.
Active, opinionated AI tool usage: "I use Copilot but I still read what it generates" is the right
answer; "I paste whatever it outputs" is not. This is evaluated explicitly.
Comfortable asking questions when stuck - after you've done your own research first.
Nice to Have
ASP.NET Core, Entity Framework, or broader .NET ecosystem experience.
Dependency injection, repository patterns, or similar architectural concepts.
Azure or another cloud platform.
ORM or database migration tooling experience.
What You'll Get
Competitive hourly compensation, tiered by experience (undergraduate and graduate rates;
details shared during the process).
A dedicated mentor - weekly 1:1s, structured code review sessions, and long enough runway to own a feature from design to production.
Work that ships - features you build will go to production users during the internship.
Real code review under the same standards applied to the full-time team - not the kind that
approves everything.
AI tooling stipend (Cursor Pro, Claude Pro, or equivalent) - the AI-native expectation is real; we
remove the financial barrier to getting there.
Priority consideration for full-time roles upon graduation.
Location & Hybrid Policy
This role is based in Glendale, CA. We expect 3 days on-site per week, with flexibility around
academic schedules communicated in advance. Fully remote arrangements are not offered.
Candidates who cannot commit to regular on-site presence in Glendale are not a fit for this program.
How to Apply
Send your resume. If you have code to share - GitHub, a school project, anything - include a link
and note the part you're most proud of (or most embarrassed by; honest reflection is more useful
than a curated portfolio). Applications are reviewed on a rolling basis.
Moon is committed to building a diverse and inclusive team. We encourage applications from
candidates of all backgrounds, institutions, and experience levels. We evaluate based on
demonstrated ability, not credentials.
The pay range for this role is:
25 - 35 USD per hour (Moon HQ)