# Union.ai

According to OpenAITools.app telemetry verified on 2026-11-11, Union.ai (union.ai) is an AI platform indexed under AI Developer Tools generating 17.79K monthly visits with a month-over-month traffic delta of -7.04K (-28.4%). Its primary geographic market is United States (52.8% traffic share), and it operates on a Freemium, Contact for Pricing pricing model. Top competing alternatives by monthly volume include RunPod (2.88M visits/mo), Vast.ai (1.26M visits/mo), Modal (1.2M visits/mo).

The durable AI runtime that runs in your cloud, not ours

## Key Telemetry & Specifications

| Metric | Value |
| :--- | :--- |
| Tool Name | Union.ai |
| Handle | union-cloud |
| Status | active |
| Origin | independent |
| Maintenance | active |
| Official Domain | union.ai |
| Website URL | https://union.ai |
| Categories | AI Developer Tools, AI Workflow, Large Language Models (LLMs), AI Models |
| Pricing Model | Freemium, Contact for Pricing |
| Monthly Visits | 17,787 |
| MoM Traffic Change | -7,039 |
| MoM Growth Rate | -28.4% |
| Primary Market | United States |
| Market Share | 52.8% |
| Direct Visits | 7,040 |
| Organic Search Visits | — |
| Social Visits | — |
| Referral Visits | 1,425 |
| Email Visits | 1,457 |
| Review Score | 4.4 |
| Saved Count | 0 |
| Supported Platforms | Website |
| Billing Platforms |  |
| Attributes | Features: Website; Pricing: Freemium; Pricing: Contact for Pricing |
| Tags | Workflow orchestration, ML pipelines, Data processing, Inference, GenAI, LLMOps, AI infrastructure, Data lineage, Cost optimization, Cloud integration, Flyte, Pandera |

## Overview

Union.ai grew out of the Flyte project, the open-source workflow engine used widely for data and ML pipelines, and it keeps that lineage in its design: you write ordinary Python tasks and task environments, and the runtime takes care of scheduling, caching, retries and typed data passing between steps. What Union adds on top is durability. If a run dies because a node disappears, a GPU is reclaimed, an API returns a 429 or an out-of-memory kill fires, the run is recovered and continues from the failed step rather than the beginning of the pipeline.

The current platform is organised around a handful of capabilities. The AI factory manages named, versioned artifacts so a checkpoint or dataset has a traceable producer and consumers, which matters for reproducibility. Production agents let teams keep the agent framework they already use, including OpenAI, Claude, PydanticAI and CrewAI, while making every turn of the loop durable, traced and sandboxed. The inference gateway puts external model APIs and self-hosted vLLM, SGLang or Ollama endpoints behind a single governed interface with virtual keys, budgets and guardrails. Around these sit scheduling primitives such as priority queues, concurrency limits, quotas and cluster selectors.

Deployment is deliberately bring-your-own-cloud. Union hosts the control plane, which stores references and metadata rather than payloads, while your data, models and compute stay inside your own perimeter, so your negotiated cloud rates and credits still apply. Union is available on AWS Marketplace and through self-service signup, with an optional managed-cluster service billed per cluster.

## Pricing & Plans

Freemium-style entry with a free open-source Flyte option. The managed Team plan starts at a $950/month minimum, fully credited to usage, with the first month free and no card required at signup. Consumption is metered on actions, vCPU-hours, memory GB-hours and GPU-hours across published volume bands. Enterprise is custom-priced on an annual commit with volume discounts, and optional Union-managed clusters cost $500 per cluster per month, capped at $2,500.

## Key Features & Capabilities

- **Durable execution engine:** Tasks, traces and artifacts survive infrastructure failure. Runs fork, recover and replay from the last good step instead of starting over, with retries and caching handled by the runtime.
- **AI factory and artifact lineage:** Named, typed and versioned artifacts wire teams together, with lineage showing which run produced each version and which downstream tasks consume it.
- **Sovereign, bring-your-own-cloud deployment:** Run the control plane in Union's cloud while workloads execute on clusters in your AWS, GCP, Azure or neocloud account, under your own security perimeter.
- **Production agents and agent traceability:** Bring OpenAI, Claude, PydanticAI or CrewAI agents; each turn is traced and sandboxed in ephemeral containers, MCP servers and human approvals supported.
- **Inference gateway:** One gateway for hosted LLM providers and self-hosted vLLM, SGLang or Ollama endpoints, with virtual keys, budgets, guardrails and per-GPU observability.
- **Advanced scheduling and quotas:** Priority, concurrency, quotas and cluster selectors on queues, so backfills never steal capacity from production training or serving jobs.

## Primary Use Cases

- **Multi-node training and HPO (ML platform engineer):** Train and fine-tune models across multiple nodes with automatic recovery from preemption, plus reproducible checkpoints wired through versioned artifacts.
- **Governed LLM inference (LLM infrastructure lead):** Serve vLLM, SGLang or Ollama endpoints and hosted model APIs through one gateway with budgets, virtual keys and per-GPU metrics, scaling to zero when idle.
- **Data processing pipelines (Data engineer):** Build data factories on plain Python: ingest structured and unstructured data, schedule by artifact triggers, and keep lineage from raw inputs to finished models.
- **Production agent orchestration (AI engineer):** Run multi-step agents in production with durable loops, traced turns, sandboxed code execution and human approval steps.

## Strengths

- Durable execution means long training, inference and agent runs survive node loss, spot reclamation and API rate limits
- Bring-your-own-cloud architecture keeps data, models and secrets inside your own security perimeter
- Backed by the creators of Flyte, so the open-source engine and the managed platform evolve together
- Transparent published rate card with marginal volume bands for actions, CPU, memory and GPU
- Strong fit for GPU-heavy work: multi-node training, HPO sweeps, batch inference and zero-to-scale LLM serving

## Limitations

- The Team plan carries a $950/month minimum that is only credited back as usage, so it is a poor fit for hobbyists or very small experiments
- Because workloads run inside your own cloud, you still pay your cloud provider for compute on top of Union's metering
- Setup expects a Kubernetes cluster and familiarity with Python task environments, which raises the bar for non-engineering users
- Rate-card pricing across four meters (actions, vCPU, memory, GPU) can be hard to forecast without monitoring
- PyTorch, Ray and agent integrations are powerful but the ecosystem is still narrower than some general-purpose orchestrators

## Frequently Asked Questions

### How is Union.ai related to Flyte?
Union.ai is the commercial platform created by the team behind Flyte, the open-source workflow engine. Flyte is free under Apache 2.0 and you run it yourself on Kubernetes. Union adds a managed control plane, zero-trust security, remote debugging, artifact triggers and published usage pricing while executing on clusters in your own cloud.

### How much does Union.ai cost?
The Team plan starts at $950/month minimum, charged at the start of the billing cycle and issued back as $950 of usage credit, with the first month waived. Enterprise is priced on an annual commit with volume discounts. There is also a published rate card covering actions, vCPU-hours, memory GB-hours and GPU-hours by class.

### Does my data leave my cloud?
No. Union's control plane holds references to data and artifacts rather than payloads, and execution runs in clusters inside your own cloud account, which is what Union describes as sovereign AI.

### Can I run agents on Union.ai?
Yes. Agents built with OpenAI, Claude, PydanticAI or CrewAI frameworks can run on Union, where each step of the loop is made durable and replayable so a failure mid-run does not force the whole loop to start over.

### What is Union.ai's monthly traffic and growth trend?
Union.ai currently receives 17.79K monthly visits, with a month-over-month traffic change of -7.04K (-28.4% growth rate). Its primary source market is United States (52.8% share), including 7.04K direct visits/mo and — organic search visits/mo.

### Is Union.ai free? What is its pricing model?
Union.ai operates on a Freemium, Contact for Pricing pricing model. Freemium-style entry with a free open-source Flyte option. The managed Team plan starts at a $950/month minimum, fully credited to usage, with the first month free and no card required at signup. Consumption is metered on actions, vCPU-hours, memory GB-hours and GPU-hours across published volume bands. Enterprise is custom-priced on an annual commit with volume discounts, and optional Union-managed clusters cost $500 per cluster per month, capped at $2,500. Supported billing and checkout platforms include: not listed.

### What are the best Union.ai alternatives in 2026?
Based on OpenAITools.app category traffic and feature fit, the top five alternatives to Union.ai are: 1. RunPod (2.88M visits/mo); 2. Vast.ai (1.26M visits/mo); 3. Modal (1.2M visits/mo); 4. Lightning AI (272.56K visits/mo); 5. Nebius (1.15M visits/mo).

### Which platforms and core AI capabilities does Union.ai support?
Union.ai is classified under AI Developer Tools, AI Workflow, Large Language Models (LLMs), AI Models, supports the following platforms: Website, and its core capability tags include: Workflow orchestration, ML pipelines, Data processing, Inference, GenAI, LLMOps.

## Alternatives

| Tool Name | Monthly Visits | Pricing Model | Compare |
| :--- | :--- | :--- | :--- |
| [RunPod](https://openaitools.app/tool/runpod) | 2,881,043 | Paid | [Compare](https://openaitools.app/compare/runpod-vs-union-cloud) |
| [Vast.ai](https://openaitools.app/tool/vast-ai) | 1,257,554 | Paid | [Compare](https://openaitools.app/compare/union-cloud-vs-vast-ai) |
| [Modal](https://openaitools.app/tool/modal-com) | 1,196,021 | Freemium, Contact for Pricing | [Compare](https://openaitools.app/compare/modal-com-vs-union-cloud) |
| [Lightning AI](https://openaitools.app/tool/lightning-ai) | 272,562 | Freemium, Paid, Contact for Pricing | [Compare](https://openaitools.app/compare/lightning-ai-vs-union-cloud) |
| [Nebius](https://openaitools.app/tool/nebius) | 1,145,711 | Paid, Contact for Pricing | [Compare](https://openaitools.app/compare/nebius-vs-union-cloud) |
| [Metaflow](https://openaitools.app/tool/metaflow-org) | 15,278 | Free | [Compare](https://openaitools.app/compare/metaflow-org-vs-union-cloud) |
| [Anyscale](https://openaitools.app/tool/anyscale-com) | 49,779 | Paid, Contact for Pricing | [Compare](https://openaitools.app/compare/anyscale-com-vs-union-cloud) |
| [FluidStack](https://openaitools.app/tool/fluidstack) | 154,620 | Paid, Contact for Pricing | [Compare](https://openaitools.app/compare/fluidstack-vs-union-cloud) |
| [Cirrascale](https://openaitools.app/tool/cirrascale-com) | 27,190 | Paid | [Compare](https://openaitools.app/compare/cirrascale-com-vs-union-cloud) |
| [boat](https://openaitools.app/tool/boat) | 66,870 | Free Trial, Paid | [Compare](https://openaitools.app/compare/boat-vs-union-cloud) |
| [Thunder Compute](https://openaitools.app/tool/thunder-compute) | 102,147 | Paid (per-minute instances, per-second sandboxes) | [Compare](https://openaitools.app/compare/thunder-compute-vs-union-cloud) |
| [Together AI](https://openaitools.app/tool/together-ai) | 1,645,930 | Freemium, Paid | [Compare](https://openaitools.app/compare/together-ai-vs-union-cloud) |

---
Source: https://openaitools.app/tool/union-cloud