> AI agents: this is one page from PostHog's docs. Full index of Markdown docs for LLMs: https://posthog.com/llms.txt

# Linking Membrain as a source

![](https://res.cloudinary.com/dmukukwp6/image/upload/texture_tan_9608fcca70)

![](https://res.cloudinary.com/dmukukwp6/image/upload/texture_tan_dark_a92b0e022d)

Let AI connect your sources for you

Skip the manual setup — run this in your project and the wizard auto-detects your databases and APIs and connects them to PostHog.

`npx @posthog/wizard warehouse`

![PostHog Wizard hedgehog](https://res.cloudinary.com/dmukukwp6/image/upload/wizard_3f8bb7a240.png)

![](https://res.cloudinary.com/dmukukwp6/image/upload/wizard_3f8bb7a240.png)Let AI connect your sources for you

**Alpha release**

This source is currently in **alpha**. The interface and available tables may change.

The Membrain connector syncs companies, contacts, prospects, and more into the PostHog data warehouse, so you can analyze them alongside your product data.

## Prerequisites

Credentials that can read the data you want to sync. PostHog only reads data, so read access is enough.

## Adding a data source

1.  In PostHog, go to the [Sources tab](https://app.posthog.com/data-management/sources) of the data pipeline section.
2.  Click **\+ New source** and click **Link** next to this source.
3.  Enter your credentials (see [Configuration](#configuration) below) and click **Next**.
4.  Select the tables you want to sync, choose a sync method and frequency, then click **Import**.

Once the syncs are complete, you can start querying this data in PostHog.

Enter your Membrain API key and account subdomain to sync your CRM data, including companies, contacts, prospects, sales projects, and tickets.

A Membrain admin can create an API key under **System Setup → Membrain API**. Your subdomain is the first part of your Membrain URL. For `acme.membrain.com` the subdomain is `acme`.

You'll be asked for:

-   **API key**
-   **Account subdomain**: for example `acme`.

## Sync modes

Each table can be synced in one of several modes, depending on what the source supports:

-   **Webhook** (when available) – the source pushes changes to PostHog in real time. Fastest freshness, lowest ongoing cost, and the only mode that reliably captures updates and deletes.
-   **Incremental** – only new or updated rows are synced on each run, using a cursor field (such as an `updated_at` timestamp). Cheaper than a full refresh, but deletes aren't captured.
-   **Append only** – new rows are appended using a cursor field; existing rows are never updated. Ideal for immutable, append-only tables like event logs.
-   **Full refresh** – the whole table is reloaded on every sync. Use it when a table has no reliable cursor or when you need deletions reflected.

See [sync methods](/docs/cdp/sources.md#sync-methods) for a full explanation of how each mode works and how to choose between them.

All Membrain tables are full refresh. Each sync replaces the contents of the table.

## Configuration

| Option | Type | Required |
| --- | --- | --- |
| `API key` | password | Yes |
| `Account subdomain` | text | Yes |

## Supported tables

| Table | Description | Sync method | Incremental field | Primary key |
| --- | --- | --- | --- | --- |
| `companies` | Companies (accounts) in the Membrain CRM, including deleted ones. | Full refresh | — | — |
| `contacts` | Contacts (people) in the Membrain CRM, including deleted and retired ones. Custom field values appear as CustomField columns. | Full refresh | — | — |
| `prospects` | Prospecting-pipeline items. A prospect's human-readable key has the form P-{n}. | Full refresh | — | — |
| `opportunities` | Sales projects (opportunities). A sales project's human-readable key has the form SP-{n}. | Full refresh | — | — |
| `account_growth_items` | Account growth projects. An account growth project's human-readable key has the form AGP-{n}. | Full refresh | — | — |
| `tickets` | Support or service tickets. A ticket's human-readable key has the form T-{n}. | Full refresh | — | — |
| `activities` | Activities: tasks, appointments, calls, notes, and emails. Unset dates use the sentinel value 1753-01-01 00:00:00. | Full refresh | — | — |
| `users` | Membrain users. Every user is also a contact; additional properties such as title and phone number live on the contacts table. | Full refresh | — | — |
| `roles` | Roles that can be assigned to a stakeholder on a project (for example Accountable or Approver). | Full refresh | — | — |
| `custom_fields` | Custom field definitions across entity types. One row per definition, with EntityType naming the entity the field belongs to. | Full refresh | — | — |
| `products` | Products that can be attached to sales projects. | Full refresh | — | — |

## Troubleshooting

-   If the connection fails with an authorization error, the API key is wrong, expired, or has been revoked. Create a new one, then reconnect the source.
-   If a table syncs no rows, the credential may not have access to that data. Check its permissions, then reconnect the source.

If your sync is failing or data looks wrong, see the [Data warehouse troubleshooting guide](/docs/data-warehouse/troubleshooting.md). If that doesn't help, [contact support](https://us.posthog.com/#panel=support%3Asupport%3Adata_warehouse%3A%3Atrue) – we're happy to help.

### Still have questions?

Ask PostHog AI

### Was this page useful?

HelpfulCould be better