---
title: 'Research Engineer, AI Safety & Alignment at Character.AI'
canonical: 'https://feeny.ai/job/research-engineer-ai-safety-alignment-character-ai-redwood-city-p2gtwtpvekg7'
type: 'job'
last_seen: '2026-11-05'
---

# Research Engineer, AI Safety & Alignment at Character.AI

- **Company:** Character.AI
- **Location:** Redwood City, CA
- **Compensation:** $225k–$400k
- **Employment:** full-time
- **Work type:** hybrid
- **Posted:** 2025-10-03
- **Last confirmed live:** 2026-11-05
- **Apply:** https://jobs.ashbyhq.com/character/a7ddb640-466f-4a1f-9a94-7465006aad05/application

**Skills:** Python, GPU programming, Transformers, Reinforcement Learning, Machine Learning, Data pipelines, Data infrastructure, Product experimentation, A/B testing, Distributed model training, ML deployment, Kubernetes, Docker, Cloud computing, Explainable AI, Interpretability techniques

> As a Research Engineer in AI Safety & Alignment, you will conduct foundational research to mitigate advanced AI risks and ensure models behave according to human values. You will develop evaluation methodologies, perform adversarial testing, and integrate safety solutions into products while bridging theoretical res...

## Job description

## About the role and team

Joining us as a Research Engineer, you'll be at the forefront of tackling one of the most critical challenges in AI today: safety and alignment. Your work will be pivotal in understanding and mitigating the risks of advanced AI, conducting foundational research to make our models safer, and solving the core technical problems of AI alignment—ensuring our models behave in accordance with human values and intentions. The Safety team is dedicated to pioneering and implementing techniques that make our models more robust, honest, and harmless. As a Research Engineer, you will bridge the gap between theoretical research and practical application, writing high-quality code to test hypotheses and integrating successful safety solutions directly into our products. Your research will not only protect millions of users but also contribute to the broader scientific community's understanding of how to build safe, beneficial AI.

## What you'll do

- Develop and implement novel evaluation methodologies and metrics to assess the safety and alignment of large language models.
- Research and develop cutting-edge techniques for model alignment, value learning, and interpretability.
- Conduct adversarial testing to proactively uncover potential vulnerabilities and failure modes in our models.
- Analyze and mitigate biases, toxicity, and other harmful behaviors in large language models through techniques like reinforcement learning from human feedback (RLHF) and fine-tuning.
- Collaborate with engineering and product teams to translate safety research into practical, scalable solutions and best practices.
- Stay abreast of the latest advancements in AI safety research and contribute to the academic community through publications and presentations.

## Who you are

- Hold a PhD (or equivalent experience) in a relevant field such as Computer Science, Machine Learning, or a related discipline.
- Write clear and clean production-facing and training code
- Experience working with GPUs (training, serving, debugging)
- Experience with data pipelines and data infrastructure
- Strong understanding of modern machine learning techniques, particularly transformers and reinforcement learning, with a focus on their safety implications.
- Are passionate about the responsible development of AI and dedicated to solving complex safety challenges.

## Nice to Have

- Experience with product experimentation and A/B testing
- Experience training large models in a distributed setting
- Familiarity with ML deployment and orchestration (Kubernetes, Docker, cloud)
- Experience with explainable AI (XAI) and interpretability techniques.
- Have research in AI safety, alignment, ethics, or a related area.
- Knowledge of the broader societal and ethical implications of AI, including policy and governance.
- Publications in relevant academic journals or conferences in the field of machine learning

## About Character.AI

[Character.AI](http://Character.AI) empowers people to connect, learn and tell stories through interactive entertainment. Over 20 million people visit [Character.AI](http://Character.AI) every month, using our technology to supercharge their creativity and imagination. Our platform lets users engage with tens of millions of characters, enjoy unlimited conversations, and embark on infinite adventures.

In just two years, we achieved unicorn status and were honored as Google Play's AI App of the Year—a testament to our innovative technology and visionary approach.

Join us and be a part of establishing this new entertainment paradigm while shaping the future of Consumer AI!

At Character, we value diversity and welcome applicants from all backgrounds. As an equal opportunity employer, we firmly uphold a non-discrimination policy based on race, religion, national origin, gender, sexual orientation, age, veteran status, or disability. Your unique perspectives are vital to our success.

## About Character.AI

## Company Overview
- **One-liner**: Character.AI builds a full-stack, direct-to-consumer platform where users interact with AI-powered "Characters" for open-ended conversation, storytelling, and entertainment.
- **Entity Type**: Private (Venture Capital-Backed)
- **Headquarters**: Menlo Park, California, United States
- **Founded**: 2021
- **Founders**: Noam Shazeer and Daniel De Freitas

## Core Business
- **Primary industry/industries**: Entertainment Software, Artificial Intelligence & Machine Learning, SaaS (B2C)
- **Target customers**: B2C — millions of monthly active users seeking virtual companions, creative storytelling, and interactive entertainment.
- **Mission or purpose statement**: "Empower people to connect, learn, and tell stories through interactive entertainment."

## Products & Services
- **Character.AI Platform**: A web and mobile application that allows users to create, discover, and converse with AI Characters. The platform supports user-generated content, enabling users to build heroes, settings, stories, and challenges. It sits at the intersection of storytelling, gaming, social connection, and creative expression.

## Market Standing
- **Valuation/Market Cap**: Not publicly disclosed (latest known round: Secondary Transaction - Private, completed at "Generating Revenue" stage per PitchBook).
- **Key Metric**: Total Funding raised — **$193M** (Series A: $43.1M in 2022; Series A extension/round: $150M in March 2023).
- **Notable Investors/Partners**: Andreessen Horowitz, Google, Greycroft, SV Angel, Elad Gil, and 8 total investors. [cbinsights.com](https://www.cbinsights.com/company/characterai)
- **Growth Signals**: 
    - Millions of monthly active users.
    - Headcount of ~130 employees as of 2026.
    - Offices in Silicon Valley (HQ), Seattle, and New York.
    - The company completed a "Reverse Acqui-Hire" transaction, signaling strong talent acquisition interest from larger players.

## Competitive Advantages
- **Deep Technical Talent**: Founded by AI pioneers Noam Shazeer and Daniel De Freitas, who bring deep expertise in machine learning and natural language processing.
- **Full-Stack AI Platform**: Unlike many chatbot APIs, Character.AI owns the entire stack from model inference to consumer interface, giving them control over user experience and data.
- **Strong User Engagement & Community**: The platform has built a passionate community of creators and users who generate and share content, creating a network effect moat.
- **Brand Recognition**: One of the leading independent consumer AI platforms globally, with a clear identity as an entertainment-first product.

## Strategic Focus
- **AI-driven Entertainment**: The company is focused on redefining entertainment through generative AI, moving beyond simple chatbots into immersive, interactive experiences.
- **User-Generated Content (UGC)**: Empowering users to create their own characters and worlds is a core strategic priority, differentiating them from single-purpose AI tools.
- **Monetization & Scale**: Moving from a free product toward a sustainable business model (subscription tiers like c.ai+) while scaling the platform to serve a global user base.
- **Talent Acquisition**: Actively hiring across ML research, engineering, and safety to build out the next generation of their product.

## Why Work Here
- **Mission-Driven Work**: Opportunity to work on cutting-edge generative AI and shape the future of entertainment for millions of users.
- **High-Impact Environment**: Described as a "small, passionate team" where individuals can have significant ownership and influence.
- **Strong Compensation**: Competitive salaries (e.g., Research Engineer, AI Safety & Alignment: $225K–$400K + equity). [jobs.ashbyhq.com](https://jobs.ashbyhq.com/character/)
- **Comprehensive Benefits**:
    - **Parental Leave**: 20 weeks paid for birthing parents, 12 weeks for non-birthing parents.
    - **Retirement**: 401(k) match up to $5,875/year (25% of contributions up to IRS cap).
    - **Time Off**: 20 days accrued PTO, 12 company-paid holidays, plus accrued sick time.
    - **Health**: 100% premium coverage for medical (PPO or HSA), dental, and vision for employees; 80% for dependents. Life, AD&D, and LTD insurance fully covered.
    - **Perks**: Daily lunch in all offices, monthly DoorDash credit, monthly commuter allowance ($50), and a quarterly wellness stipend.
- **Work Policy**: Hybrid (offices in Menlo Park, Seattle, New York).
- **Culture Values**: "Users First" (users > company > team), "Think Transformational," and a focus on collaboration and high performance.

## Sources
1. [character.ai/about](https://character.ai/about)
2. [character.ai/careers](https://character.ai/careers)
3. [jobs.ashbyhq.com/character/](https://jobs.ashbyhq.com/character/)
4. [cbinsights.com](https://www.cbinsights.com/company/characterai)
5. [pitchbook.com](https://pitchbook.com/profiles/company/512290-54)

## Other roles at Character.AI

- [Technical Program Manager, Product Experience](https://feeny.ai/job/technical-program-manager-product-experience-character-ai-redwood-city-m9zmhkmgt1qy) — Redwood City, CA
- [Principal Research Engineer, Post-Training](https://feeny.ai/job/principal-research-engineer-post-training-character-ai-redwood-city-92f6f7sk06h1) — Redwood City, CA
- [Technical Program Manager, Model Alignment and Deployment](https://feeny.ai/job/technical-program-manager-model-alignment-and-deployment-character-ai-redwood-brmkpc2gvra0) — Redwood City, CA
- [Staff Data Scientist, Monetization](https://feeny.ai/job/staff-data-scientist-monetization-character-ai-redwood-city-51hmwhgh6e2k) — Redwood City, CA
- [Technical Program Manager, AI Infrastructure](https://feeny.ai/job/technical-program-manager-ai-infrastructure-character-ai-redwood-city-3ty4trwmewr9) — Redwood City, CA
- [Software Engineer, Backend/Applied ML (Safety & Integrity)](https://feeny.ai/job/software-engineer-backend-applied-ml-safety-integrity-character-ai-redwood-city-4q5mdjeptsz5) — Redwood City, CA
- [Software Engineer, Applied ML (Discovery, Recommendation & Search)](https://feeny.ai/job/software-engineer-applied-ml-discovery-recommendation-search-character-ai-5r4a2m0v7fzq) — Redwood City, CA
- [Software Engineer, Backend](https://feeny.ai/job/software-engineer-backend-character-ai-redwood-city-kx5x7rxznvz7) — Redwood City, CA
- [Software Engineer, Monetization](https://feeny.ai/job/software-engineer-monetization-character-ai-redwood-city-4wjqzcp5e490) — Redwood City, CA
- [Software Engineer, Core Product](https://feeny.ai/job/software-engineer-core-product-character-ai-redwood-city-h676pc9pz8k1) — Redwood City, CA