Mid/Senior AI LLM Engineer - EverAI

Our Vision & Products

EverAI is building the future of AI companionship. With over 50 million users in two years, we are creating entirely new product categories. Our flagship product is the world's largest AI companionship platform, governed by our proprietary moderation system, EverGuard—an internal AI designed to keep everything safe, ethical, and human-first.

Our Team

We are an enthusiastic, passionate, and hardworking team of ~100 people. Our founding leadership team brings extensive experience scaling web products from 0 to IPO and multi-million dollar exits across tech, e-commerce, and AI.

Your Role

Most LLM roles stop at experimentation. Here, the models you improve power experiences for 50M+ users. Most of our traffic runs on self-hosted, fine-tuned open-weight models. On internal roleplay evals, our smaller fine-tuned models outperform much larger off-the-shelf models. Your job is to make them better.

You will join a small AI team led by our LLM Tech Lead, working closely with our CTO, Product, Web, and DevOps teams across data, post-training, evals, and model behavior.

Key Responsibilities

• Fine-tune open-weight LLMs using SFT, LoRA/QLoRA, and post-training methods such as DPO and GRPO.
• Diagnose model failures and convert them into actionable experiments across data, post-training, prompting, or classifiers.
• Build training data and evals that directly shape future model iterations.
• Improve model behavior across personalization, character consistency, tone, multilingual support, and group interactions.
• Ship to production and leverage real user behavior to guide iterations.
• Accelerate training loops for faster, reproducible, and easier-to-compare experiments.

Your Qualifications

• Personally post-trained open-weight LLMs for a user-facing product and shipped them to production.
• Worked in environments where AI was core to the product or business, not just a side experiment.
• Deep hands-on experience with fine-tuning.
• Strong expertise in Python, PyTorch, and Hugging Face, including hands-on GPU training and debugging.
• Proven ability to build data pipelines and evals independently based on evidence.
• Track record of taking work beyond notebooks into production systems.
• Daily user of AI tools in your engineering workflow.
• Comfortable working with uncensored models and explicit NSFW content, including harmful material when developing and evaluating moderation systems.

Bonus Points

• Experience with conversational AI, roleplay products, or personalized consumer AI.
• Expertise in multilingual LLMs, multimodal models, or safety and adversarial testing.
• Contributions to open-source LLMs or post-training frameworks.

What We Offer

• Work From Anywhere: 100% remote working setup.
• Contract Flexibility: B2B or standard contracts focused on long-term commitment.
• Paid Time Off: 4 weeks (20 working days) of PTO annually.
• Annual Gathering: Yearly in-person team meetup.
• Health & Wellness Support: $100 USD monthly health allowance plus unlimited 1:1 sessions with psychologists via OpenUp for you and up to three family members.
• Co-Working Budget: Allowance for co-working space visits twice per month ($35 EUR / $40 USD per visit).
• Learning Budget: Dedicated funds for courses, books, conferences, and certifications.
• Equipment Provision: Company laptop, plus budgets for a monitor ($250 USD) and peripherals ($150 USD).
• AI Tools Access: Premium subscriptions to ChatGPT, Hugging Face, Claude Code, and required dev tools.