AfterQuery — Software Engineer, RL Environments

davidjoseph-co; San Francisco (CA); On-site; USD 180,000 - 220,000; Full time

Benefits offered by this job

Competitive equity

Job summary

AfterQuery in San Francisco, CA is seeking a Software Engineer for RL Environments to design data slices and evaluation rubrics powering frontier model training.

You will own end-to-end data pipelines, experiment with RLHF/RLVR signals, and collaborate with research teams to translate training objectives into concrete data and evaluation specs. 1–4 years of software engineering experience required; on-site work. Competitive compensation with equity and rapid impact in a small, early-stage team.

Qualifications

• 1–4 years of software engineering experience.
• Design targeted data slices to surface model failure modes across domains.
• Build and iterate evaluation rubrics powering RLHF/RLVR pipelines.
• Develop quantitative frameworks to measure dataset quality, diversity, and impact on model alignment.
• Own end-to-end real-world and synthetic data pipelines, from scoping to production-ready evaluation specs.
• Run annotator modeling experiments to improve model capabilities.

Responsibilities

• Design data slices and explore data shapes that expose meaningful model failure modes across domains.
• Build and refine evaluation rubrics and reward signals for RLHF and RLVR training pipelines.
• Model annotator behavior and run experiments to improve model capabilities.
• Develop quantitative frameworks to measure dataset quality, diversity, and downstream impact on model alignment and capability.
• Create and manage both real-world and synthetic data pipelines.
• Partner with lab research teams to translate training objectives into concrete data and evaluation specs.

Skills

Software engineering

Data pipelines

RLHF/RLVR

Experimentation

Model evaluation

Job description

AfterQuery — Software Engineer, RL Environments

Type: Full-time | On-site | San Francisco, CA Compensation: $180,000–$220,000 + competitive equity (see comp note below) Hiring count: 3 Visa sponsorship: O-1, OPT Reports to: Not specified (initial screen: Alec; second round: Michael/Sam)

About AfterQuery

AfterQuery builds the training data and evaluation infrastructure that frontier AI labs use to improve their models, designing high‑signal datasets and running rigorous evaluations that go beyond static benchmarks. It's a small, early team (post–Series A) where individual contributors have direct impact on how the next generation of models learns. The founding team comes from Jane Street, Citadel, Google, Goldman, and Stanford AI Lab.

Founded: 2025 | Team size: 11–50 | Total funding: $30M raised (~$300M valuation) | Industry: Consumer Tech | Website: afterquery.com | Office: San Francisco, CA

Why Candidates Should Join

• Outsized total cash: $200K base plus profit share of roughly 150% of base, bringing expected total cash to around $500K, plus competitive equity.
• Direct line to frontier models: Output feeds directly into model training runs at scale, working hands‑on with research teams at top AI labs.
• High ownership, early team: Small post–Series A team where ICs scope, build, and ship end to end.

The Role

As a SWE (Environments), you design the datasets and evaluation rubrics that directly influence how frontier models learn — going from hypothesis to live experiment quickly, with output feeding directly into model training.

What You'll Be Doing

• Design data slices and explore data shapes that expose meaningful model failure modes across domains like finance, code, and enterprise workflows.
• Build and refine evaluation rubrics and reward signals for RLHF and RLVR training pipelines.
• Model annotator behavior and run experiments to improve different model capabilities.
• Develop quantitative frameworks for measuring dataset quality, diversity, and downstream impact on model alignment and capability.
• Create and manage both real‑world and synthetic data pipelines.
• Partner with lab research teams to translate their training objectives into concrete data and evaluation specifications.

Tech stack: Not specified

Requirements

• 1–4 years of software engineering experience with strong technical depth.
• Design targeted data slices that surface model failure modes across high‑stakes domains (finance, code generation, enterprise workflows).
• Build and iterate on evaluation rubrics and reward signals powering RLHF and RLVR training pipelines.
• Develop quantitative frameworks to measure dataset quality, diversity, and downstream impact on model alignment and capability.
• Own end‑to‑end real‑world and synthetic data pipelines, from scoping with research teams to production‑ready evaluation specs.
• Run annotator modeling experiments to improve model capabilities across task types.

Green Flags

• Experience at RL environment companies.
• Background in AI safety or benchmarking organizations like METR or Artificial Analysis.
• Genuine obsession with how data structure, selection, and quality drive model behavior.
• Ability to design lightweight experiments and move fast.
• Former founders or early engineers at early stage startups.
• Demonstrated ability to work hard, learn fast, and care deeply about details.

Red Flags

• Pure research profile with limited engineering output; this is a SWE role, shipping matters.
• Looking for standard product engineering work — the real scope is data pipelines, reward modeling, and eval infra.