Polyrouter vs TensorZero
Polyrouter
polyrouter.app
TensorZero
tensorzero.comSide by side
| Figure | Polyrouter | TensorZero |
|---|---|---|
| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| Web | Yes | Yes |
| Linux | — | Yes |
| API | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 1 | 1 |
| Spec score · LLM gateways | 7.8 (#21) | 8.6 (#7) |
| Spec score · LLM Gateway Software | 7.6 (#22) | 8.0 (#13) |
| Deployment | Self-hosting requires Docker with Compose v2 and runs the SPA, API, and proxy alongside PostgreSQL 16 and Redis. | The gateway can be deployed with Docker, Docker Compose, Kubernetes using a reference Helm chart, or built from source with Cargo. |
| Integrations | Provider options include API keys, OAuth subscriptions, compatible custom endpoints, and self-hosted local models including Ollama, LM Studio, and llama.cpp. | Documented providers include Anthropic, AWS Bedrock, Azure, Google, OpenAI, OpenRouter, Together AI, vLLM, and OpenAI-compatible endpoints. |
| License | Polyrouter is open source under the AGPL-3.0 license. | The FAQ describes TensorZero as open source under the Apache 2.0 License. |
| Privacy | Request logs are metadata-only by default, and prompt or response capture is an opt-in self-hosted feature that is off by default. | The gateway documentation says its pseudonymous usage analytics do not include application data or inference inputs and outputs, and can be disabled. |
| Product | Polyrouter is an open-source LLM gateway that puts one endpoint in front of multiple model providers. | TensorZero is an open-source platform that combines an LLM gateway, observability, evaluation, optimization, and experimentation. |
| Security | Provider and notification credentials are encrypted at rest, and user-supplied URLs are checked against private and metadata address ranges. | TensorZero's privacy policy says it uses physical, technical, organizational, and administrative security measures to protect personal data. |
| Support | The maker directs bug reports, feature requests, and questions to GitHub. | The project README directs users to Slack or Discord and offers work teams a Slack or Teams channel by email. |
Plans
In their own words
Polyrouter
Polyrouter has no write-up on Specifiction yet; its figures are above.
TensorZero
TensorZero is a free, open-source stack that brings together an LLM gateway, observability, optimization, evaluation, and experimentation. Its gateway provides a unified API for model providers and supports routing, retries, fallbacks, prompt templates, schemas, multi-step workflows, and traffic routing for A/B tests. Documented integrations include Anthropic, AWS Bedrock, Azure, Google, OpenAI, OpenRouter, Together AI, vLLM, xAI, and OpenAI-compatible endpoints. Inference and feedback data go to the database you configure, where they can be queried with SQL; feedback can be tied to individual inferences or episodes. The gateway and UI can run through Docker, Docker Compose, Kubernetes and Helm, or a source build. API key authentication is available for gateway endpoints other than status and health checks. The project is available on GitHub, but is no longer maintained; its repository is archived and read-only. TensorZero is self-hosted and licensed under Apache 2.0. It collects pseudonymous aggregate usage analytics, excluding application data and inference inputs and outputs, with an option to disable collection.