# Carbon vs. Plex

> Plex (by Rockwell) is a mature cloud ERP+MES built for high-volume, repetitive plants — capable, closed, cloud-only, and priced by quote. Carbon is open and self-hostable, exposes the whole backend over API and MCP, and runs high-volume assembly and prototype parts on one model — without the enterprise weight or lock-in.

## Scope & fit

| | Carbon | Plex |
| --- | --- | --- |
| What it is | ERP + MRP + MES + QMS on one data model | Cloud ERP + MES + QMS suite |
| Built for | Discrete manufacturers, from prototype to rate production | High-volume, repetitive discrete & process (automotive) |
| Volume range | High-volume assembly and prototype parts in one system | High-volume plants; not built for small runs |

## Capabilities

| | Carbon | Plex |
| --- | --- | --- |
| Shop-floor execution (MES) | Yes | Yes |
| Quality (QMS) | Yes | Yes |
| Scheduling & capacity planning | Live; updates as the floor reports | Supply-chain planning via DemandCaster module |
| Serial & batch traceability | Yes | Yes |
| Product configurator (CPQ) | Yes | No |
| 3D CAD / STEP viewer | Built in | CAD-to-work-instructions authoring |

## Platform & ownership

| | Carbon | Plex |
| --- | --- | --- |
| Deployment | Cloud or self-host | Cloud-only SaaS; no on-prem |
| Full ownership of the code | Yes — the entire codebase is yours | No — proprietary |
| API coverage | Full backend over REST — every table | REST/JSON API + webhooks (selected endpoints) |
| AI / agent-ready (MCP) | Hosted MCP over the full backend | Embedded AI features; no public MCP |
| ITAR / GovCloud / CMMC | ITAR, GovCloud & CMMC / NIST 800-171 ready | IATF 16949 / automotive quality focus |

## Getting started

| | Carbon | Plex |
| --- | --- | --- |
| Implementation | Self-serve; live in days | Months to a year+; services-heavy |
| Pricing | $40–$100 / user / mo, published | Quote-only; per user + per module |

## Where Plex still fits

For a Tier-1 or Tier-2 automotive supplier running high-volume lines across plants, Plex is a mature, proven cloud ERP+MES backed by Rockwell's automation ecosystem. Carbon gives you the same unified model — open, self-hostable, and transparently priced — running high-volume assembly and prototype parts side by side, without the enterprise weight or lock-in.

## You may be outgrowing Plex if…

- **You run more than high-volume lines.** Plex is built for high-volume, multi-plant production and says so. Carbon runs those same lines and the prototype and low-volume work beside them — one model, any volume.
- **Cloud-only, closed, and quoted.** Plex holds your backend in a shared cloud you can't self-host. Carbon is open-source — own the data and run it where you like.
- **You want the whole backend for agents.** Plex's AI is embedded features. Carbon exposes the entire backend over a hosted MCP server your agents can act on.

## Why manufacturers choose Carbon

- **One system across every run size.** Plex is built for high-volume, repetitive plants. Carbon runs high-volume assembly and one-off prototype parts on the same ERP, MRP, MES and QMS model, so mixed and low-volume work isn't a second-class fit.
- **Open and API-first.** The whole backend is open over REST and MCP, with full source access and no lock-in. Run Carbon in the cloud or self-host it, and point the best agents (Claude, ChatGPT, Cursor) at your live data instead of a vendor's built-in assistant.
- **Live capacity planning built in.** Plex plans demand through the separate DemandCaster module. Carbon's capacity and demand update the moment the floor reports progress — on the same record, with nothing extra to license.
- **Right-sized and open.** Start free for 30 days on published, per-user pricing with a self-serve rollout — instead of an enterprise platform sized and priced for large plants.

Start a 30-day free trial at https://app.carbon.ms, see pricing at https://carbon.ms/pricing, or read the source at https://github.com/crbnos/carbon.