Senior Software Engineer ($160k-$200k + Equity) at Numero
Jack & Jill · United States
- Hybrid
- Full-time
- $180,000 / year
- United States
Tailored resume — keyword-matched to this role.
Hiring manager — we find who's hiring.
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Job highlights
- Architect and scale backend systems for a YC-backed platform.
- Work with Ruby on Rails, Postgres, and OpenSearch.
- Integrate AI agents and LLM-powered features.
- Optimize high-volume payment processing systems.
- Directly impact national campaigns and fundraising efforts.
About the role
Senior Backend Engineer
This is a job that Jill, our AI Recruiter, is recruiting for on behalf of one of our customers. She will pick the best candidates from Jack's network. The next step is to speak to Jack.
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.
Company Description
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.
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
- Senior Backend Engineer
- Ruby on Rails
- Postgres
- OpenSearch
- SQL
- System Architecture
- AI Integration
- LLM
- Payment Processing
- Scalability
Skills & topics
- Senior Backend Engineer
- Ruby on Rails
- Postgres
- OpenSearch
- SQL
- System Architecture
- AI Integration
- LLM
- Payment Processing
- Scalability
- Backend Development
- YC-backed
- Remote
- USA
How to get hired
- Tailor your resume: Highlight your 6+ years of backend experience, SQL proficiency, and AI integration skills.
- Showcase production experience: Emphasize your understanding of production performance, cost optimization, and scaling systems.
- Demonstrate AI enthusiasm: Mention any experience with AI-integrated engineering workflows or LLM-powered features.
- Prepare for technical interviews: Brush up on Ruby on Rails, Postgres, OpenSearch, and SQL for high-volume data.
- Understand the mission: Be ready to discuss how your work contributes to political campaigns and nonprofits.
Technical preparation
Review Ruby on Rails concepts and best practices.,Practice complex SQL queries and database optimization.,Study system design for high-traffic applications.,Explore AI agent and LLM integration patterns.
Behavioral questions
Describe a time you scaled a backend system.,How do you ensure production performance and cost?,Discuss your experience with AI-integrated workflows.,How do you handle complex payment processing challenges?
Frequently asked questions
- What is the role of a Senior Backend Engineer at Numero?
- As a Senior Backend Engineer at Numero, you will architect and scale backend systems using Ruby on Rails, Postgres, and OpenSearch. You'll work on integrating AI agents and LLM-powered features, and optimize payment processing for national campaigns.
- What are the key technologies used by the Senior Backend Engineer at Numero?
- The Senior Backend Engineer role at Numero primarily utilizes Ruby on Rails, Postgres, and OpenSearch. Experience with SQL, AI integration, and tools like Cursor for AI-driven workflows is also important.
- What kind of impact will a Senior Backend Engineer have at Numero?
- The impact is significant; your work directly supports political campaigns and nonprofits by powering a fundraising platform that has helped raise over $10 billion. You'll be building mission-critical systems at a high-growth startup.
- What experience is required for the Senior Backend Engineer role at Numero?
- The ideal candidate has 6+ years of experience building and scaling user-facing backend systems, with strong SQL skills for high-volume environments, and a good understanding of production performance and cost.
- How does the Jack & Jill recruitment process work for this Senior Backend Engineer role?
- Jill, an AI Recruiter, identifies candidates from Jack's network for this Senior Backend Engineer role. If it's a match, Jill's client (Numero) will initiate the next steps, often involving a call with Jack first.
- Is this Senior Backend Engineer role remote?
- Yes, this Senior Backend Engineer position at Numero is fully remote within the USA.
- What does YC-backed mean for a company like Numero?
- YC-backed signifies that Numero has gone through the prestigious Y Combinator accelerator program, indicating strong potential, innovation, and support from experienced mentors and investors. It suggests a high-growth trajectory.
- What is NumeroQL and how is it relevant to the Senior Backend Engineer role?
- NumeroQL is Numero's proprietary engine. As a Senior Backend Engineer, you will be responsible for scaling this engine, which is central to the platform's data handling and request processing capabilities.