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Attio App SDK · Data quality

Subdomain Merge for Attio

Version 1.4 · Ready for Attio review · August 2026

Find Company records whose domains share one registrable domain. Review every candidate, choose the primary and merge from a native Attio action.

Read the safety guideExplore the Attio App Store

The 60 second overview

What it finds: root domains and subdomains that resolve to the same eTLD+1 through the Public Suffix List.

What it protects: shared platforms, ambiguous multi domain records and stale previews are excluded before any write.

What it changes: only a merge that a user previews and confirms. There is no background automation and no external service account.

01 / How it works

Deduplication with a deliberate human gate.

Subdomain Merge turns a risky cleanup into a visible three step review. The scan is manual. The proposed primary stays editable. The final action remains explicit.

01 / Scan

Find safe candidates

Open the Companies action and scan current domains. Public suffix rules separate company domains from shared hosting platforms.

02 / Review

Inspect every record

Compare names, domains and populated attributes. Keep the recommendation or choose another primary before continuing.

03 / Confirm

Merge and verify

Confirm the destructive action. The app follows the new Attio record identifier and verifies that the final Company is readable.

02 / In Attio

The evidence stays close to the decision.

Every screenshot and the demonstration below come from the dedicated Attio sandbox used for product validation.

Subdomain Merge from install to resultInstallation, authorization, scan, review and a verified final record
Subdomain Merge scan showing candidate Company groups in Attio
Scan Company domainsManual discovery with protected platform exclusions
Subdomain Merge preview showing the selected primary Company
Review the primaryNames, domains and populated attributes before write
Subdomain Merge result confirming the final Attio Company record
Verify the new recordResponse status and readable final Company
03 / Documentation

Safe by default, explicit at every write.

Installation

Once Subdomain Merge is available through the Attio App Store, a workspace admin can install it from Workspace settings, then Apps. The action appears on the Companies object list and in the command palette.

The app requests read and write access to records plus read access to object configuration. It uses the official App SDK token and the public Attio REST API only.

Usage

  1. Open the Companies list.
  2. Choose Scan subdomain duplicates from the object actions menu.
  3. Review the candidate group and every warning.
  4. Keep the proposed primary or choose another record.
  5. Select Merge records, then read and accept the destructive confirmation.
  6. Wait for the final Company verification before taking another action.

The primary record wins when both records contain a value for the same attribute. Attio creates a new record identifier for every merge.

Matching safeguards

CheckBehavior
Public suffixDomains are reduced to eTLD+1 with the Public Suffix List.
Private suffixShared platforms such as GitHub Pages and Vercel are excluded.
Ambiguous recordA Company spanning unrelated registrable domains is excluded.
Name mismatchThe group remains visible with an extra review warning.
Primary conflictA richer secondary is highlighted when the root record is proposed.
Stale previewThe server revalidates the exact group before calling merge.

Behavior and limits

  • The scan runs only when a user opens the action or selects Rescan.
  • No candidate is merged automatically.
  • The merge endpoint is beta and limited by Attio to five requests per second.
  • A successful merge returns a new record identifier that replaces both source identifiers.
  • A 202 response is followed through the new identifier until the record becomes readable. The merge request is never repeated.
  • A transport failure leaves the state unknown. The app never retries the non idempotent request and instructs the user to rescan.
  • Groups larger than twenty records require a smaller review scope.
  • The current manual scan covers up to 5,000 Company records in one action.

Support

For installation help, a protected platform question or an uncertain merge state, email support@buildrhaus.com. Include the workspace name and the visible result message. Never include Attio API keys or credentials.

Terms and privacy

Subdomain Merge is provided by Buildrhaus for use with Attio. It runs on Attio hosted App SDK infrastructure and calls only the public Attio REST API with the token granted to the installed app. Buildrhaus does not operate a separate data processing backend for this app.

Users remain responsible for reviewing candidates, choosing the intended primary and confirming each merge. Record merge is destructive and produces a new Attio record identifier. The endpoint is currently beta, so behavior may evolve as Attio updates its public API.

The service is provided without a separate uptime commitment. Buildrhaus may update the app to maintain compatibility, safety and reliability. General website terms and privacy information are available in the legal notice and privacy policy.

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