Senior Software Engineer, Machine Learning Infrastructure - Generative AI

DoorDash USA; San Francisco (CA); On-site; USD 137,100 - 201,600; Full time

Benefits offered by this job

401(k) plan with employer matching

16 weeks of paid parental leave

Wellness benefits

Job summary

DoorDash USA in San Francisco is searching for a senior engineer to lead the design and architecture of its Generative AI infrastructure. You will oversee the model serving stack, ensuring performance and reliability while mentoring your team.

You should have a strong background in backend engineering, particularly in Python and distributed systems, along with technical leadership experience. This role also offers a generous benefits package, including flexible paid time off and a 401(k) plan.

Qualifications

• 6+ years of industry experience in software engineering.
• Experience operating systems in production, including observability and performance optimization.
• Deep hands-on experience with LLM inference and fine-tuning.

Responsibilities

• Lead the design of infrastructure for Generative AI at DoorDash.
• Own and evolve the open-weights serving stack and related platforms.
• Architect scalable, high-performance systems for model serving.

Skills

Backend engineering fundamentals

Python

Distributed systems

Technical leadership

AI coding tools

Education

B.S., M.S., or PhD. in Computer Science

Tools

Kubernetes

AWS/GCP

Job description

About the Team

DoorDash’s GenAI Platform team sits within Machine Learning Platform and builds the shared infrastructure that helps DoorDash, Wolt, and Deliveroo teams safely bring GenAI‑powered products, agents, automation, and personalization to production. Our mission is to increase the velocity of business impact from GenAI. A central pillar of that work is running frontier open‑weight LLMs and VLMs (such as GLM, Qwen, Kimi, and DeepSeek) ourselves — real‑time GPU serving, high‑throughput batch inference, and fine‑tuning on autoscaling GPUs — delivering large cost and latency wins (for example, a billion embeddings produced roughly 20× cheaper and visual models served roughly 72% cheaper). We also own core platform surfaces including the LLM Gateway, Agent Gateway, evals infrastructure, guardrails, and cost attribution.

About the Role

You will join a small, high‑leverage team building production infrastructure for Generative AI at DoorDash, leading the design and architecture of our open‑weights model platform spanning inference and fine‑tuning: real‑time GPU serving, high‑throughput batch inference, and model fine‑tuning. You’ll set technical direction across model serving and inference engines, fine‑tuning and training pipelines, GPU autoscaling and utilization, batch pipelines, backend services, and observability, and mentor engineers as you go. This role is ideal for a senior engineer who enjoys owning ambiguous, high‑impact systems and pushing the cost/performance frontier of GPU inference and fine‑tuning in a fast‑moving technical area where product needs, model capabilities, vendor ecosystems, and cost/performance tradeoffs are evolving quickly.

You’re excited about this opportunity because you will…

• Lead the design of infrastructure that helps DoorDash teams move GenAI ideas from prototype to production, increasing the velocity of business impact from AI across the company.
• Own and evolve our open‑weights serving stack — real‑time GPU endpoints, high‑throughput batch inference, and fine‑tuning (SFT/DPO/LoRA) — alongside the LLM Gateway, Agent Gateway, evals infrastructure, guardrails, and cost attribution.
• Architect scalable, high‑performance systems for model serving, batch inference, GPU autoscaling, and fine‑tuning that power real customer and internal automation use cases.
• Push the cost and latency frontier of GPU inference — turning batch jobs that took days into hours and cutting inference cost by multiples — while giving product teams a clean choice across open‑weight and closed‑source models with reliability, fallback, observability, and cost controls built in.
• Build platforms that support rapid experimentation while meeting production standards for latency, scale, monitoring, SLOs, playbooks, and operational excellence.
• Partner closely with — and raise the technical bar for — ML engineers, product engineers, data scientists, and platform teams across DoorDash, Wolt, and Deliveroo to turn emerging GenAI capabilities into durable platform primitives.
• Set technical direction for the future of DoorDash’s centralized GenAI platform — including emerging directions such as reinforcement learning (RLHF/RLVR), agent optimization, and other post‑training and agentic techniques — enabling the next generation of AI‑powered products, agents, automation, and personalization.

We’re excited about you because…

• B.S., M.S., or PhD. in Computer Science or equivalent.
• 6+ years of industry experience in software engineering.
• Deep backend engineering fundamentals, especially in Python and distributed systems.
• Track record of designing and owning production services, APIs, data pipelines, or ML infrastructure at scale.
• Experience operating systems in production, including observability, debugging, reliability, incident response, and performance/cost optimization.
• Deep hands‑on experience with LLM inference and/or fine‑tuning of open‑weight models in production — serving (latency, throughput, batching, autoscaling, GPU utilization) and/or fine‑tuning (SFT/DPO/LoRA).
• Demonstrated technical leadership: leading design across ambiguous, fast‑moving technical areas, mentoring engineers, and turning customer use cases into reusable platform capabilities.
• Proficiency in using AI coding tools (e.g., Claude Code, Codex, Cursor) in the full software development lifecycle, including designing, generating code, testing, monitoring and releasing software.

Nice To Haves

• Experience with LLM inference engines and serving frameworks (e.g., vLLM, SGLang, TensorRT‑LLM) in production.
• Experience with distributed/multi‑node fine‑tuning and training pipelines (SFT, DPO/RLHF, LoRA), including data preparation and evaluation.
• GPU performance work — multi‑node/distributed inference, KV‑cache/memory optimization, quantization (FP8/INT8/AWQ/GPTQ), or cold‑start/throughput tuning.
• Experience with Kubernetes, cloud infrastructure (AWS/GCP), GPUs, serverless/elastic GPU platforms (e.g., Modal), or high‑throughput batch systems.
• Experience with LLM gateways, model routing, vendor abstraction, or cost attribution.
• Experience building developer platforms, internal platforms, or self‑serve infrastructure.
• Experience building and deploying AI agents or MCP servers in production.
• Experience with eval systems, LLM observability, tracing, RAG, search, or vector databases.

Compensation

The successful candidate’s starting pay will fall within the pay range listed below and is determined based on job‑related factors including, but not limited to, skills, experience, qualifications, work location, and market conditions. Base salary is localized according to an employee’s work location. Ranges are market‑dependent and may be modified in the future.

In addition to base salary, the compensation for this role includes opportunities for equity grants.

DoorDash offers a comprehensive benefits package to all regular employees, which includes a 401(k) plan with employer matching, 16 weeks of paid parental leave, wellness benefits, commuter benefits match, paid time off and paid sick leave in compliance with applicable laws, medical, dental, and vision benefits, 11 paid holidays, disability and basic life insurance, family‑forming assistance, and a mental health program.

Paid Time Off Details

• For salaried roles: flexible paid time off/vacation, plus 80 hours of paid sick time per year.
• For hourly roles: vacation accrued at about 1 hour for every 25.97 hours worked (e.g. about 6.7 hours/month if working 40 hours/week; about 3.4 hours/month if working 20 hours/week), and paid sick time accrued at 1 hour for every 30 hours worked (e.g. about 5.8 hours/month if working 40 hours/week; about 2.9 hours/month if working 20 hours/week).

National Pay Ranges (U.S.)

• $137,100 — $201,600 USD
• $167,800 — $246,800 USD
• $203,500 — $299,300 USD

Equality Statement

We’re committed to growing and empowering a more inclusive community within our company, industry, and cities. That’s why we hire and cultivate diverse teams of people from all backgrounds, experiences, and perspectives. We believe that true innovation happens when everyone has room at the table and the tools, resources, and opportunity to excel. Statement of Non‑Discrimination: In keeping with our beliefs and goals, no employee or applicant will face discrimination or harassment based on race, color, ancestry, national origin, religion, age, gender, marital/domestic partner status, sexual orientation, gender identity or expression, disability status, or veteran status. Above and beyond discrimination and harassment based on “protected categories,” we also strive to prevent other subtler forms of inappropriate behavior from ever gaining a foothold in our office. Whether blatant or hidden, barriers to success have no place at DoorDash. We value a diverse workforce – people who identify as women, non‑binary or gender non‑conforming, LGBTQIA+, American Indian or Native Alaskan, Black or African American, Hispanic or Latinx, Native Hawaiian or Other Pacific Islander, differently‑abled, caretakers and parents, and veterans are strongly encouraged to apply.