Senior Software Engineer

Lumilens; San Jose (CA); On-site; USD 150,000 - 210,000; Full time

Benefits offered by this job

Competitive salary

Professional development

Cutting-edge technology

Collaborative culture

Equal opportunity employer

Job summary

Lumilens is building critical photonics infrastructure for AI supercomputing. You will contribute to a high-performance, multi-threaded desktop application for optical transceiver testing, with MVVM architecture and deep hardware integration.

Collaborate with a team of engineers on scalable software powering thousands of units daily. You will work across C#/.NET, Python, and tooling like GitHub Actions, designing robust, testable solutions, and debugging remotely using telemetry and logs.

Qualifications

• 5 years of C#/.NET experience with GUI (WPF) and MVVM patterns.
• Strong concurrency knowledge and thread-safe design across multi-threaded apps.
• Experience with .NET 8 or later.
• 3 years of Python, OOP and pytest.
• Clean architecture, dependency injection, testability.
• Experience with MongoDB or similar document databases.
• Ability to debug remotely via logs and telemetry.

Responsibilities

• Develop a C#/.NET desktop application for manufacturing software with MVVM architecture.
• Integrate hardware drivers and manage instrument control across multiple tests.
• Create Python test scripts and integrate functionality into the .NET app.
• Scale software to run on manufacturing lines producing thousands of units daily.
• Collaborate with cross-functional teams to deliver robust solutions.

Skills

C#/.NET

WPF

MVVM

Async/Await

Thread safety

Concurrent programming

.NET 8+

Python

Clean architecture

Remote debugging

Tools

Git

GitHub Actions

CI/CD

PowerShell

Bash

MongoDB

Job description

About Lumilens

At Lumilens we are building the critical photonics infrastructure that powers tomorrow’s AI supercomputing. From chip-to-chip optical interconnects to scalable photonic engines, Lumilens is unlocking a new era of computing faster, cooler, and massively more efficient.

We’re a well-funded startup backed by Mayfield and led by veterans who’ve built and scaled some of the most transformative technologies in the industry. This isn’t incremental innovation, it’s a ground-floor opportunity to rethink the optical layer from the silicon up. You’ll work alongside a team of world-class engineers solving some of the hardest challenges in optics, systems, and scale. Every line of code, every design decision, every breakthrough you help deliver will shape the infrastructure of tomorrow.

If you’re looking for mission, momentum, and the chance to make an outsized impact—jump on the rocket ship. We’re just getting started … and we are building a Team in Kraków!

What You Will Work On

• C# / .NET desktop application — Advanced manufacturing software for optical transceiver testing. A GUI application built with MVVM architecture, featuring multi-threaded test execution, instrument resource management, and RPC services.
• Hardware integration — Writing drivers and control code for laboratory equipment, managing parallel test execution and handling complex locking across instruments.
• Python test scripts & libraries — Our manufacturing software draws the best from both worlds. You will have the opportunity to integrate complex testing functionality based on Python code embedded natively into the .NET application.
• Manufacturing scale – You will be developing software that runs on manufacturing lines, producing thousands of units daily.

Required Skills:

• 5 years of C#/.NET — experience with GUI (WPF or similar framework), MVVM, async/await, thread safety, and class library design
• Strong command of concurrent programming — designing thread-safe systems, avoiding race conditions, and reasoning about execution across multiple threads and processes
• Experience with .NET 8 or later
• 3 years of Python — OOP, pytest, abstraction-driven design
• Solid understanding of clean architecture — separation of concerns, dependency inversion, dependency injection, and testability
• MongoDB or similar document database — data modeling, querying, and managing test results at scale
• Analytical mindset — proven ability to break down complex multi-component failures, trace issues across process boundaries, and design reliable solutions under ambiguity
• Ability to debug remotely without direct debugger access — diagnosing issues via logs, traces, and telemetry

Infrastructure & Tooling

• Git & CI/CD fluency — GitHub Actions, artifact pipelines, versioning strategies, and automated deployment to remote Windows machines
• Bash and/or PowerShell scripting for automation, remote management, and deployment
• Systems-level thinking

Nice to Have

• Experience with test and measurement instruments (oscilloscopes, spectrum analyzers, power meters)
• Experience with Unit Tests: xUnit, MSTest, etc.
• Knowledge of optical communications, photonics, or transceiver technology
• Python.net experience
• Familiarity with hardware interfaces — serial communication, TCP sockets, low-level protocols and interfaces (I2C, GPIB), and instrument communication standards (SCPI, VISA)
• Familiarity with factory/manufacturing software or MES integration

What we offer

• Competitive salary commensurate with experience
• Professional development opportunities and certification support
• Access to cutting-edge technology and cloud platforms
• Collaborative work environment with cross-functional teams
• Lumilens is an equal opportunity employer. All qualified applicants will receive consideration without regard to race, color, religion, gender, identity, orientation, veteran status, disability, or any other legally protected status.