Junior Software Engineer (SWE 1)

About Downstream

Downstream is a marketplace platform transforming the waste and construction industries from the ground up. We're on a mission to bring simplicity, transparency, and sustainability to two of the most essential — but often overlooked — sectors of our economy.

We make it easy for contractors, builders, and businesses to find and book critical services like dumpster rentals, hauling, site services, and equipment — all in a few clicks. No endless calls, no confusing pricing, no waiting around. Our platform connects customers with vetted, reliable providers so they can get what they need, when they need it.

We're not just about convenience — we're about impact. By streamlining logistics and digitizing the supply chain, we're helping reduce waste, cut emissions, and build a cleaner, more sustainable future. Let's build better, together.

About the role

We're looking for a Junior Software Engineer to help build and improve the Django applications, APIs, and data models that power the Downstream marketplace. You'll work on clearly scoped projects with support from experienced engineers, learning how our platform connects customers, suppliers, pricing, and logistics. You'll also begin contributing to AI-enabled product capabilities, including integrations and well-defined steps in agentic workflows.

What you'll do

• Implement well-defined features and fixes in our Django and Python applications with guidance from senior engineers
• Build and maintain REST API endpoints, data models, and integrations that support marketplace workflows
• Write readable, maintainable code and contribute unit and integration tests
• Work with relational data in PostgreSQL or a similar database, including basic queries, migrations, and data validation
• Assist with integrating AI capabilities using tools such as OpenAI APIs, LangChain, or other approved frameworks
• Contribute to small, clearly scoped automation tasks and learn how multi-step AI workflows interact with application data and business logic
• Participate in code reviews, technical discussions, and debugging; communicate blockers early and incorporate feedback
• Document your work and follow established development, testing, security, and deployment practices

Role specifics

• Ownership: delivers scoped tasks with clear requirements and support from more experienced engineers
• Technical focus: Django, Python, REST APIs, relational data, testing, and core development workflows
• AI exposure: contributes to contained AI integrations and workflow components; learns safe, reliable patterns for using LLMs in production
• Quality expectations: prioritizes correctness, maintainability, tests, and clear communication over unnecessary complexity

Who you are

• You've built something with Python and Django through coursework, a personal project, an internship, or professional experience
• You understand foundational programming concepts, HTTP, REST APIs, and relational database fundamentals
• You're curious about AI-native software and interested in how LLMs and agents can work with users, data, and business logic
• You can break down a task, ask thoughtful questions, communicate blockers, and respond constructively to feedback
• You value readable code, testing, collaboration, and continuous learning
• You're comfortable working in a startup environment where priorities can evolve

Compensation

$70,000–$90,000 per year (Series A compensation band).

Benefits

Downstream is an equal opportunity employer. We consider all applicants for employment without regard to race, color, religion, sex, sexual orientation, gender identity or expression, national origin, age, disability, genetic information, veteran status, or any other protected status under applicable law.

• Medical, dental, and vision insurance
• 401(k) with a company match
• Company equity — be an owner in what we're building
• Paid time off, paid holidays, and floating holidays
• Parental and bereavement leave