Weekday AI (YC W21)
Founding Software Engineer (Full-Stack)
Weekday AI (YC W21) - San Francisco, California, United States, 94199
Work at Weekday AI (YC W21)
Overview
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Overview
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This role is for one of the Weekday's clients
Salary range:
$150K - $190K / 2.00% - 3.00%
Experience: 3+
YoE
We are seeking a highly skilled
Founding Software Engineer (Full-Stack)
to join our team in San Francisco, CA. This role focuses on solving the challenge of automating all the time-consuming tasks developers face outside their code editor — from deployments to performance, incidents, and bug resolution — using agentic workflows and AI.
You will work directly with two experienced co-founders: one who has led engineering efforts at scale for internal developer platforms used by thousands of engineers, and another who has successfully founded, scaled, and sold a developer-focused startup.
Requirements
Key Responsibilities
Event-Driven Backend Development: Architect a Node.js / Next.js / TypeScript and Supabase stack. Design schemas, event flows, and ingest dev tools webhooks to power a real-time personalized engineering portal. LLM Agentic Workflows: Build a system of AI agents, incorporating MCP, tool usage, memory, retry logic, context updates, and feedback loops. Agent Experience (AX): Design intuitive human-agent interaction interfaces, collaborating closely with engineers to refine productivity-focused digital co-pilots. System Design & Technical Strategy: Partner with leadership to define scalable technical paths, balancing rapid delivery with integration flexibility for diverse developer tools and open-source community support.
Ideal Candidate Profile
Full-stack 0-to-1 builder with production deployment experience, particularly in rapidly shipping Next.js applications and event-driven, serverless architectures. Strong interest in agentic product experiences and the impact of AI on developer productivity. Prior experience as a founder or founding engineer who has built products from scratch that gained real users or paying customers. Problem-solver who thrives on tackling hard challenges with grit and persistence. Comfortable navigating ambiguity, prioritizing effectively, and adapting to changing circumstances. Excellent communication skills with a high degree of candor and openness. Deep commitment to supporting engineers in overcoming operational inefficiencies.
This Role is Not a Fit If You
Are not based in the Bay Area (team will be co-located in San Francisco). Are unwilling to work six days a week (Sundays off). Are not excited about leveraging modern code-generation tools (e.g., Cursor, Windsurf, Claude Code). Are uncomfortable with frequent deletion/refactoring of large portions of code. Prefer rigid structures over dynamic, fast-changing environments. Avoid direct and honest feedback exchanges.
The Opportunity
Work alongside two seasoned co-founders — one with deep experience scaling developer platforms, and another with proven success building and exiting a dev tools startup. Gain end-to-end startup exposure, from customer support and user interviews to events and core development. Become the first engineering hire at a company aiming to define the next category-leading developer platform used and paid for by leading tech companies
Seniority level
Seniority level Mid-Senior level Employment type
Employment type Full-time Job function
Job function Other Industries IT Services and IT Consulting Referrals increase your chances of interviewing at Weekday AI (YC W21) by 2x Get notified about new Software Engineer jobs in
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Salary range:
$150K - $190K / 2.00% - 3.00%
Experience: 3+
YoE
We are seeking a highly skilled
Founding Software Engineer (Full-Stack)
to join our team in San Francisco, CA. This role focuses on solving the challenge of automating all the time-consuming tasks developers face outside their code editor — from deployments to performance, incidents, and bug resolution — using agentic workflows and AI.
You will work directly with two experienced co-founders: one who has led engineering efforts at scale for internal developer platforms used by thousands of engineers, and another who has successfully founded, scaled, and sold a developer-focused startup.
Requirements
Key Responsibilities
Event-Driven Backend Development: Architect a Node.js / Next.js / TypeScript and Supabase stack. Design schemas, event flows, and ingest dev tools webhooks to power a real-time personalized engineering portal. LLM Agentic Workflows: Build a system of AI agents, incorporating MCP, tool usage, memory, retry logic, context updates, and feedback loops. Agent Experience (AX): Design intuitive human-agent interaction interfaces, collaborating closely with engineers to refine productivity-focused digital co-pilots. System Design & Technical Strategy: Partner with leadership to define scalable technical paths, balancing rapid delivery with integration flexibility for diverse developer tools and open-source community support.
Ideal Candidate Profile
Full-stack 0-to-1 builder with production deployment experience, particularly in rapidly shipping Next.js applications and event-driven, serverless architectures. Strong interest in agentic product experiences and the impact of AI on developer productivity. Prior experience as a founder or founding engineer who has built products from scratch that gained real users or paying customers. Problem-solver who thrives on tackling hard challenges with grit and persistence. Comfortable navigating ambiguity, prioritizing effectively, and adapting to changing circumstances. Excellent communication skills with a high degree of candor and openness. Deep commitment to supporting engineers in overcoming operational inefficiencies.
This Role is Not a Fit If You
Are not based in the Bay Area (team will be co-located in San Francisco). Are unwilling to work six days a week (Sundays off). Are not excited about leveraging modern code-generation tools (e.g., Cursor, Windsurf, Claude Code). Are uncomfortable with frequent deletion/refactoring of large portions of code. Prefer rigid structures over dynamic, fast-changing environments. Avoid direct and honest feedback exchanges.
The Opportunity
Work alongside two seasoned co-founders — one with deep experience scaling developer platforms, and another with proven success building and exiting a dev tools startup. Gain end-to-end startup exposure, from customer support and user interviews to events and core development. Become the first engineering hire at a company aiming to define the next category-leading developer platform used and paid for by leading tech companies
Seniority level
Seniority level Mid-Senior level Employment type
Employment type Full-time Job function
Job function Other Industries IT Services and IT Consulting Referrals increase your chances of interviewing at Weekday AI (YC W21) by 2x Get notified about new Software Engineer jobs in
San Francisco, CA . San Francisco, CA $160,000.00-$180,000.00 2 weeks ago San Francisco, CA $130,000.00-$238,000.00 2 weeks ago San Francisco, CA $150,000.00-$250,000.00 2 weeks ago Full-Stack Software Engineer (Jr/Mid level)
San Francisco, CA $120,000.00-$180,000.00 1 month ago San Francisco, CA $150,000.00-$230,000.00 3 months ago Software Development Engineer I - Frontend & Mobile
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San Francisco, CA $57.00-$61.00 2 days ago San Francisco, CA $165,000.00-$165,000.00 2 years ago San Francisco, CA $120,000.00-$200,000.00 2 years ago Alameda, CA $130,000.00-$160,000.00 2 months ago San Francisco, CA $140,000.00-$280,000.00 8 months ago We’re unlocking community knowledge in a new way. Experts add insights directly into each article, started with the help of AI.
#J-18808-Ljbffr