1,665,992open jobs
99,800companies
256,005added this week
Browse all
Salary
$150k – $250k per year
Location
In office (San Francisco)
Seniority
Middle · 3+ years exp
Employment
Full-Time

Confirmed on the employer's own hiring board on Oct 15, 2026. First seen by Alion on Oct 14, 2026.

Overview
Company
Impact
Profile match
Headquartered in San Francisco, California, TrainLoop is an artificial intelligence research and product lab specializing in post-training reasoning models for long-horizon tasks. Founded in 2024, the enterprise develops advanced reinforcement learning and fine-tuning solutions to transform general foundation models into domain-specific experts for industries such as biotechnology, logistics, and financial services. By embedding human expert intuition and rigorous preference alignment into proprietary architectures, the company enables organizations to deploy highly reliable AI agents for complex, mission-critical workflows.
Backed by Y Combinator

Develop new methods for building specialized models that learn reliably and solve difficult tasks. We’re hiring research scientists across post-training, reinforcement learning, continual learning, multimodal models, evaluation, and interpretability. Your research focus will depend on your strengths and the questions you pursue with the team.

You might develop new training methods, investigate how models acquire and retain skills, design evaluations for long-horizon reasoning, study model internals, or explore architectures and learning strategies for specialized domains. You’ll formulate hypotheses, implement and run experiments, compare against meaningful baselines, and work with research engineers to turn useful findings into practical capabilities. Communicate results clearly, including limitations and competing explanations.

Requirements

  • Typically 3+ years of relevant ML research experience, or equivalent demonstrated research contributions. Relevant doctoral research counts toward experience.
  • Independent drive for research. Top candidates can discuss at length contemporary research in language model training.
  • At least one substantial original research contribution demonstrated through a paper or open-source implementation.
  • Depth in at least one of post-training, reinforcement learning, continual learning, multimodal learning, evaluation, interpretability, systems, or inference.
  • For work focused on model training: typically 1+ year of hands-on language or multimodal model training, including doctoral research, or equivalent completed training projects.
Free account
Stop reading job ads. Get the ones that fit.
One free account turns this page into a shortlist built around your stack, your level and your pay.
Match on every job. Stack, seniority, pay and location, scored against your profile.
1,665,992 open roles. Read straight off company career pages, refreshed every day.
Unlimited applications. Every one you send is tracked in one place, on-site or on a company board.
3 tailored CVs a month. Rewritten for the exact job you are applying to. Included free.
Create a free account Continue with Google
Free forever. No card. Under a minute.

Your match

How well do you fit this role?
Two answers are enough for a real match. No account needed.
Check my fit
Answers stay in this browser until you create an account.

Recommended for you based on this role

AI/ML
Similar stack
Same company
San Francisco
$180k – $260k per year • In office • 5+ years exp • Bachelor's Degree • Chicago
Python
AI/ML
Time Series Forecasting
DevOps
Linux
TCP/IP
Apply
$180k – $300k per year • In office • Chicago
Databases
Apache Kafka
AI/ML
AI Agents
LLM
Human-in-the-Loop
LLM Guardrails
DevOps
CI/CD
Apply
≈ $74k – $140k per year (Estimated) • In office • 3+ years exp • Dallas
Python
Python
Flask
FastAPI
Django
Asyncio
Aiohttp
Databases
Redis
Apache Kafka
AI/ML
AutoGen
LangChain
LlamaIndex
Fine-tuning
Prompt Engineering
AI Agents
LLM
Google ADK
LLM Guardrails
Frontend
GraphQL
Mobile
Dependency Injection
DevOps
Rest API
GCP
OpenTelemetry
Prometheus
Azure
CI/CD
AWS
IAM
API Gateway
QA
Pytest
Apply
$38k per year • In office • 8+ years exp • Dallas
Python
JavaScript
AI/ML
Copilot
Claude
Fine-tuning
Prompt Engineering
NLP
TensorFlow
PyTorch
Gemini
RAG
OpenAI
Anthropic
Multi-Agent Systems
Analytics
A/B Testing
Apply
$144k – $181k per year • Equity • Hybrid • 4+ years exp • Boston
Python
SQL
Databases
Snowflake
AI/ML
XGBoost
Scikit-learn
Multimodal AI
Computer Vision
AI Agents
NumPy
PyTorch
Amazon SageMaker
Machine Learning
DevOps
GitHub Actions
AWS
Docker
Apply
≈ $127k – $307k per year (Estimated) • In office • Full-Time • Bachelor's Degree • San Francisco
Python
AI/ML
CUDA Toolkit
Fine-tuning
AI Agents
ONNX
TensorRT
PyTorch
Anomaly Detection
CUDA
Vision-Language-Action
World Models
Physical AI
Robotics
ROS2
Isaac Sim
Teleoperation
Sim-to-Real
Imitation Learning
OpenVLA
Apply
≈ $71k – $140k per year (Estimated) • In office • 3+ years exp • San Francisco
DevOps
Windows
Cybersecurity
Okta
SOC 2
Microsoft Entra ID
Management
Slack
Confluence
Jira
Google Workspace
Gmail
ITSM
Apply
In office • Full-Time • San Francisco
Marketing
HubSpot
LinkedIn
Apply
$120k – $135k per year • In office • 3+ years exp • Bachelor's Degree • San Francisco
Management
Microsoft Office
Apply
$185k – $300k per year • Hybrid • Full-Time • 10+ years exp • Fargo • Irving • San Francisco • Des Moines • Concord
Apply
See all jobs
This is one of many
1,665,992 more open roles from verified company boards, updated every day.