Mechanize is a small, elite San Francisco vendor (founded April 2025 by ex-Epoch AI researchers Matthew Barnett, Tamay Besiroglu, and Ege Erdil) that builds a small number of robust, high-fidelity RL environments and evals for frontier coding agents, selling to leading AI labs. Its stated long-term mission is the full automation of valuable economic work via simulated 'digital office' environments.
Raised
$9.1M ↑ $9.1M
Headcount
11-50
Founded
2025
SOC 2
unknown
Researchers
yes
Open src
no
Backers: Nat Friedman, Daniel Gross, Patrick Collison
AfterQuery is a San Francisco applied-research lab and data platform (YC W25) that supplies frontier AI labs with expert-generated human data (SFT, RL rubrics), agent/RL environments, and computer-use trajectories, drawn from a large network of verified practitioners. It publishes real-task benchmarks such as Terminal-Bench, VADER, FinanceQA, and IDE-Bench, positioning around capturing how domain experts (engineers, financial analysts, lawyers) reason.
Raised
$30.5M ↑ $30M
Headcount
51-200
Founded
2025
SOC 2
unknown
Researchers
yes
Open src
yes
Backers: Altos Ventures (lead, Series A), The Raine Group, Y Combinator
Huzzle Labs is the AI division of London-based talent platform Huzzle (founded ~2020 by Ingmar Klein, Parham Rakhshanfar, and Amit Choudhary). It positions itself as a human-intelligence data foundry that builds RL environments (code, tool-use, computer-use, long-horizon enterprise workflows), expert trajectory data, and contextual evaluations for frontier AI labs and regulated European enterprises, leveraging Huzzle's vetted PhD/expert network. It bundles environments, human data, and evals in one stack.
Raised
$6M
Headcount
11-50
Founded
2020
SOC 2
Type II
Researchers
yes
Open src
partial
Backers: 10x Founders, Angel Invest, Emerge
Datacurve is a YC W24 commercial data vendor that supplies expert-curated frontier coding data, RLHF traces, and repository-wide reinforcement learning environments (with unit-test verifiers) to foundation model labs, sourced via its Shipd bounty platform of vetted software engineers. It also publishes DeepSWE, a long-horizon agentic coding benchmark.
Raised
$17.7M
Headcount
11-50
Founded
2024
SOC 2
unknown
Researchers
yes
Open src
no
Backers: Chemistry (Mark Goldberg, lead Series A), Y Combinator, Balaji Srinivasan (seed)
Proximal is a San Francisco-based (with a Bangalore presence) research lab for coding data, building high-fidelity, long-horizon reinforcement learning environments grounded in real codebases to train and evaluate frontier coding agents. It emphasizes scalable, software-driven data engines over human contractors, and research into reward-hacking detection and 'fuzzy verifiers' that score code quality beyond functional correctness.
Raised
–
Headcount
11-50
Founded
2026
SOC 2
unknown
Researchers
yes
Open src
yes
Backers: Scribble Ventures (lead), Angels from OpenAI, Anthropic, Thinking Machines, Google DeepMind, xAI, Meta Superintelligence, Cursor and Cognition (per founders' own statements; not independently verified)
BenchFlow is an early-stage, YC-backed open-source 'environment lab' building evaluation infrastructure and a community Benchmark Hub for AI agents, with products including SkillsBench, ClawsBench (mock workplace environments) and a sandboxed agent runtime. It positions environments as 'the new data' for training and evaluating agents across domains like enterprise workflows, coding, computer use and browser tasks.
Raised
$1.0M
Headcount
1-10
Founded
2024
SOC 2
unknown
Researchers
yes
Open src
yes
Backers: Y Combinator, Pear VC, Construct Capital
Collinear AI operates a 'Simulation Lab' (SimLab) that builds sandboxed, stateful RL environments simulating enterprise users, tools (Jira, ServiceNow, Shopify, EMR, airline/hotel systems) and multi-step workflows, producing training-ready trajectories, reward signals and evals for agentic models. It also offers synthetic post-training data and LLM-judge evaluation, positioning itself around 'environment-as-a-service' for enterprise long-horizon agents.
Raised
–
Headcount
11-50
Founded
2023
SOC 2
unknown
Researchers
yes
Open src
no
Backers: Engineering Capital, Firestreak Ventures, 112 Capital (11.2 Capital)
Refresh (YC X25) builds simulation engines / RL environments with verifiable rewards for coding and computer use, partnering with frontier labs and enterprises to train AI software-engineering and computer-use 'coworker' capabilities across terminal and GUI.
Raised
–
Headcount
1-10
Founded
2025
SOC 2
unknown
Researchers
yes
Open src
no
Backers: Y Combinator
Vmax is a San Francisco reinforcement-learning startup (founded 2025 by three RL/robotics PhDs from UCL and UPenn) that automates the conversion of proprietary data and evals into RL environments for LLM-based agents, targeting long-horizon and coding tasks. Its public research includes unix-ctf, a procedural generator of capture-the-flag tasks for Unix/shell competence.
Raised
–
Headcount
1-10
Founded
2025
SOC 2
unknown
Researchers
yes
Open src
no
Backers: Race Capital, South Park Commons
Habitat Inc is an early-stage commercial vendor (2-10 employees, New York HQ) building reinforcement-learning environments for white-collar / work automation, with stated focus on code and desktop-style (computer use) interaction tasks for training agentic AI models. It appears in third-party listings of RL-environment suppliers serving AI labs. No funding, customer, or certification information is publicly available.
Raised
–
Headcount
1-10
Founded
?
SOC 2
unknown
Researchers
?
Open src
no
Pedigree: Maxim Enis (co-founder), Williams College '24; prior Ramp association
Scale AI is the data-labeling and AI-data incumbent that has extended into RL environments, offering simulated web apps, macOS/Windows-like desktop VMs, and MCP-tool environments (Slack, HubSpot, Linear) with expert-designed objectives, rubrics, and automated verifiers to train and evaluate agents on long-horizon professional workflows. Following Meta's ~$14.3B June 2025 investment (~49% non-voting stake) and founder Alexandr Wang's departure to Meta, several frontier-lab customers (OpenAI, Google, xAI) reportedly scaled back or paused engagement over conflict-of-interest concerns.
Raised
$1.6B
Headcount
200+
Founded
2016
SOC 2
Type II
Researchers
yes
Open src
no
Backers: Meta Platforms, Accel, Amazon
Modal (Modal Labs) is a New York-based, Python-native serverless cloud purpose-built for AI/ML workloads, providing on-demand GPU/CPU compute, fast-booting sandboxed containers, inference, fine-tuning, and code execution. It is execution infrastructure rather than an RL-environment vendor, but is used to run reinforcement-learning training and large fleets of parallel sandboxed environments for AI labs.
Raised
$466M ↑ $355M
Headcount
51-200
Founded
2021
SOC 2
Type II
Researchers
no
Open src
no
Backers: General Catalyst (Series C co-lead), Redpoint Ventures (Series C co-lead; earlier Series A lead), Lux Capital (earlier round lead)
Mercor is a venture-backed expert-marketplace and AI-training-data company that organizes a network of ~30,000+ domain experts (doctors, lawyers, bankers, engineers) to produce RLHF data, evaluations, and reinforcement-learning environments for frontier AI labs and enterprises. Originally an AI-recruiting platform, it pivoted to human-data/RL services and expanded its RL-environment capability through acquisitions, including the February 2026 acquisition of Sepal AI and the July 2026 acquisition of Deeptune, whose computer-use/enterprise environment platform and NYC team joined Mercor.
Raised
$492M
Headcount
51-200
Founded
2023
SOC 2
unknown
Researchers
yes
Open src
no
Backers: Felicis Ventures (led Series C and Series B), Benchmark, General Catalyst
Prime Intellect operates an open-source RL stack - the Environments Hub (2,500+ community RL environments), the Verifiers library and prime-rl training framework, plus hosted RL post-training (Lab), evals, inference and on-demand GPU compute. It positions itself as the open alternative to closed big-lab RL tooling and also trains open models (INTELLECT series).
Raised
$180M ↑ $130M
Headcount
11-50
Founded
2023
SOC 2
unknown
Researchers
yes
Open src
yes
Backers: Founders Fund (led $15M round), Menlo Ventures, Distributed Global (co-led seed)
Daytona provides secure, elastic, programmatic sandboxes ('computers') that AI agents and developers can spin up in under ~90ms to run untrusted AI-generated code in isolated, stateful runtimes. It offers a managed-hosted service plus an open-source self-hostable stack, and is positioned as agent-native execution/runtime infrastructure for code execution, computer use, and RL/eval workloads.
Raised
$31M ↑ $24M
Headcount
11-50
Founded
2023
SOC 2
Type I
Researchers
?
Open src
yes
Backers: FirstMark Capital (Series A lead; Matt Turck joined board), Pace Capital, Upfront Ventures (seed lead, Series A participant)
Deeptune was a New York-based startup building managed reinforcement-learning environments ('training gyms') for computer-use and code, where AI agents practice and are evaluated on realistic digital knowledge-work tasks (simulating tools like Slack and Salesforce). It sold these pre-built environments primarily to frontier AI labs and raised a $43M Series A led by a16z (March 2026). In July 2026 it was acquired by Mercor; the team joined Mercor and Deeptune's environment platform now sits under Mercor. It is therefore no longer ranked as an independent vendor.
Raised
$43M
Headcount
11-50
Founded
2025
SOC 2
unknown
Researchers
yes
Open src
no
Backers: Andreessen Horowitz (a16z, lead), 776, Abstract Ventures
E2B provides open-source, secure cloud sandboxes (built on Firecracker microVMs) for running AI-generated code and AI agents, offered as a hosted API with BYOC/on-prem/self-hosted options. It positions as execution infrastructure for enterprise AI agents and self-claims broad Fortune 100 adoption.
Raised
$32M
Headcount
11-50
Founded
2023
SOC 2
Type II
Researchers
no
Open src
yes
Backers: Insight Partners (Series A lead), Decibel (seed lead), Sunflower Capital
Runloop sells cloud-hosted, isolated micro-VM 'devboxes' plus blueprints, snapshots and benchmark/eval tooling that give AI coding agents a secure execution environment for development, evaluation, and reinforcement/supervised fine-tuning (RFT/SFT) loops. It is execution infrastructure for agent builders and model labs rather than an RL-data/environments vendor itself.
Raised
$7M
Headcount
11-50
Founded
2024
SOC 2
claimed
Researchers
no
Open src
yes
Backers: The General Partnership (lead), Blank Ventures, Exponent Founders Capital
General Reasoning is an AI research lab (operating research hub in London; legal entity General Reasoning, Inc. registered in the US) building open RL environments and infrastructure for training and evaluating agents over long horizons. Its OpenReward platform and Open Reward Standard (ORS) provide an open specification for connecting language models to community-built RL environments, with 330+ environments accessible through one API.
Raised
$10.9M
Headcount
11-50
Founded
2025
SOC 2
unknown
Researchers
yes
Open src
yes
Pedigree: Ross Taylor (co-founder/CEO) - ex-Meta AI/FAIR, research lead on Galac
Morph (Morph Labs) provides snapshot-based VM compute for AI agents via its Infinibranch / Liquid Metal technology, which can snapshot, branch, and restore entire computational environments in roughly 100-250ms to enable massively parallel, reversible ('Git for compute') agent rollouts, evaluations, and reasoning-time branching. It markets the platform (Morph Cloud) as infrastructure for running and scaling agent/RL verification environments rather than as an RL-environment dataset vendor itself.
Raised
–
Headcount
1-10
Founded
2023
SOC 2
claimed
Researchers
yes
Open src
yes
Backers: Christian Szegedy (reported seed/angel investor; also Chief Scientist), amount undisclosed
Turing is a large AGI-infrastructure and engineering-services company that supplies frontier AI labs with coding data, human expertise, and RL/evaluation data at scale, drawing on a global vetted developer and domain-expert network. Originally a remote-engineering talent marketplace, it now positions itself around 'AGI advancement' through code and reasoning data, including work over private/real codebases.
Raised
–
Headcount
200+
Founded
2018
SOC 2
unknown
Researchers
yes
Open src
no
HQ: Palo Alto, USA