Senior Software Engineer ($160k-$200k + Equity) at Numero
Jack & Jill · United States
- Hybrid
- Full-time
- $200,000 / year
- United States
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Job highlights
- Architect and scale backend systems for millions of requests.
- Integrate advanced AI agents into product suite.
- Optimize high-volume payment processing systems.
- Work on mission-critical systems impacting campaigns.
- Join a high-growth, YC-backed startup.
About the role
Senior Backend Engineer
Numero is a YC-backed fundraising platform that has helped political campaigns and nonprofits raise over $10B. Backed by investors like 776 and Initialized Capital, Numero provides an all-in-one CRM, payment processing, and communications toolkit that scales to serve thousands of campaigns during the most critical moments of national election cycles.
Job Description
Join Numero as a Senior Backend Engineer to architect systems handling millions of daily requests and billions of records. You will scale our proprietary NumeroQL engine, integrate advanced AI agents into our product suite, and optimize high-volume payment processing. It’s a high-impact role building the infrastructure that powers consequential national campaigns.
Location
Remote, USA
Why this role is remarkable
- Work on mission-critical systems where your code directly impacts thousands of campaigns and helps raise billions of dollars for important causes.
- Join a high-growth, YC-backed team with top-tier investors like 776 and Initialized Capital, operating at a scale few startups ever reach.
- Be at the forefront of AI-native development, utilizing agentic coding workflows and building LLM-powered features like Numero Agents on a proprietary Ruby stack.
What You Will Do
- Architect and scale backend systems using Ruby on Rails, Postgres, and OpenSearch to support billions of records and high-frequency election traffic.
- Develop and refine Numero Agents, a suite of AI-powered tools that allow clients to manage their platform using sophisticated natural language commands.
- Optimize complex payment processing and tandem fundraising features, ensuring high conversion and precise compliance reporting across Stripe and PayPal.
The ideal candidate
- Possesses 6+ years of experience building and scaling user-facing backend systems with a deep, instinctive understanding of production performance and cost.
- Demonstrates high proficiency in SQL and relational data modeling at scale, with experience managing bottlenecks and indexing in high-volume environments.
- Maintains a bias toward high-quality architectural patterns and is eager to push the frontier of AI-integrated engineering workflows using tools like Cursor.
Key skills/competency
- Backend Systems Architecture
- Ruby on Rails
- Postgres
- OpenSearch
- SQL
- Production Performance
- Cost Optimization
- AI Agents
- LLM Development
- Payment Processing
Skills & topics
- Senior Backend Engineer
- Ruby on Rails
- Postgres
- OpenSearch
- SQL
- System Architecture
- AI Integration
- Payment Processing
- YC-backed
- Remote
How to get hired
- Tailor your resume: Highlight experience with Ruby on Rails, Postgres, OpenSearch, and AI agent integration.
- Showcase impact: Quantify achievements in scaling systems, optimizing performance, and handling high volumes.
- Prepare for technical interviews: Practice SQL, system design, and coding challenges relevant to backend engineering.
- Research Numero: Understand their mission and investor base to align your application and interview responses.
Technical preparation
Practice scaling systems with Ruby on Rails.,Review Postgres and OpenSearch optimization techniques.,Prepare for SQL and data modeling challenges.,Study AI agent integration and LLM concepts.
Behavioral questions
Describe a complex system you scaled.,How do you optimize for performance and cost?,Share experience integrating AI or LLM features.,Discuss handling high-volume payment processing.
Frequently asked questions
- What is the expected salary for a Senior Backend Engineer at Numero?
- The anticipated salary range for a Senior Backend Engineer at Numero is $160,000 to $200,000 annually, plus equity. This compensation reflects the senior level of the role and the high-impact nature of the work.
- What technologies will I be using as a Senior Backend Engineer at Numero?
- As a Senior Backend Engineer at Numero, you will primarily work with Ruby on Rails, Postgres, and OpenSearch. You'll also be involved in integrating AI agents and LLM-powered features, potentially using tools like Cursor.
- Is this Senior Backend Engineer role remote?
- Yes, this Senior Backend Engineer position at Numero is a remote role, open to candidates located within the USA.
- What kind of projects can I expect as a Senior Backend Engineer at Numero?
- You can expect to architect and scale backend systems supporting billions of records and high-frequency traffic, develop AI-powered tools like Numero Agents, and optimize payment processing and fundraising features.
- What experience is required for the Senior Backend Engineer role at Numero?
- The ideal candidate for the Senior Backend Engineer role at Numero has 6+ years of experience building and scaling user-facing backend systems, with strong SQL proficiency and an understanding of production performance and cost.
- Who are the investors behind Numero?
- Numero is backed by notable investors including 776 and Initialized Capital. They are also a YC-backed company.