RETL Klaviyo Destination

condor-retl-klaviyo is a first-party Klaviyo destination connector package. It exposes retl/klaviyo through the retl.destinations entry point group.

Surfaces

• profiles accepts State upserts and submits Klaviyo Bulk Profile Import jobs. It accepts email, phone_e164, and external_id Identifiers and requires at least one of those accepted types. The surface is targetless and does not support remove operations.
• list_memberships accepts targeted State upserts and submits Klaviyo Bulk Profile Import jobs with a lists relationship. It accepts email, phone_e164, external_id, and klaviyo_profile_id Identifiers and requires at least one of those accepted types. This surface creates or updates profiles and adds them to the target list; it does not support remove operations. Logical Targets can be resolved through explicit mappings, the runtime Target Registry, or managed list lookup/create by exact list name.
• list_memberships_by_profile_id accepts targeted State upserts and removes through Klaviyo's List relationships API. It accepts only klaviyo_profile_id, supports upsert and remove, and is the surface to use for authoritative list membership reconciliation. Logical Targets can be resolved through explicit mappings, the runtime Target Registry, or managed list lookup/create by exact list name.

These surfaces use Klaviyo private API key auth with the private_api_key credential field. Successful submission returns delivery_outcome="accepted" for Bulk Profile Import surfaces because Klaviyo returns a 202 job acceptance before asynchronous profile import processing is complete. list_memberships_by_profile_id returns delivery_outcome="succeeded" because Klaviyo returns 204 after the list relationship mutation is accepted by the synchronous endpoint.

The private API key may be loaded with:

credential_namespace="destinations.klaviyo"

which creates retl.secrets["destinations.klaviyo.private_api_key"] without resolving the secret during binding construction.

Profile Rendering

Each RETL upsert record becomes one JSON:API profile object inside a profile-bulk-import-job request. RETL identifiers render to Klaviyo profile attributes as follows:

• email -> email
• phone_e164 -> phone_number
• external_id -> external_id
• klaviyo_profile_id -> profile resource id

Payload fields named first_name, last_name, organization, locale, title, image, location, anonymous_id, and properties render as Klaviyo profile attributes. Other payload fields render into the Klaviyo properties object. null payload values are omitted because Klaviyo's Bulk Profile Import API does not clear profile fields with null.

For list_memberships, the target resolves to the Klaviyo List ID and is sent as the Bulk Profile Import job's relationships.lists.data[0].id. For list_memberships_by_profile_id, the target resolves to the Klaviyo List ID in /api/lists/{id}/relationships/profiles, and each row renders as {"type": "profile", "id": "<klaviyo_profile_id>"}.

Both list surfaces support managed Targets. During normal runner execution, when a logical Target is not already mapped or present in the runtime Target Registry, the connector looks for an existing Klaviyo List with the exact target name and creates one when missing. Dry runs can plan managed list creation without creating remote lists or writing Target Registry rows.

Consent is intentionally out of scope for these surfaces. Klaviyo documents that Bulk Profile Import and List relationship mutations do not update general consent or subscription status; use Klaviyo's Subscribe or Unsubscribe Profiles APIs through separate future surfaces when consent updates are needed.

Binding Config

Shared config:

• api_revision defaults to 2026-04-15.
• transport may be injected for offline tests. When omitted, non-dry-run submissions use the connector's requests transport.

The connector owns the production API origin https://a.klaviyo.com in package code. Tests use injected transports to capture requests without changing that origin.

api_revision is namespace-loadable public config:

destination = retl.destinations.load(
    "retl/klaviyo",
    binding_name="klaviyo_primary",
    credential_namespace="destinations.klaviyo",
    config_namespace="destinations.klaviyo",
)

The namespace can provide DESTINATIONS__KLAVIYO__API_REVISION.

API Source

This connector is based on Klaviyo's official Bulk Profile Import API docs, accessed 2026-05-11:

• https://developers.klaviyo.com/en/reference/bulk_import_profiles
• https://developers.klaviyo.com/en/docs/use_klaviyos_bulk_profile_import_api
• https://developers.klaviyo.com/en/reference/add_profiles_to_list
• https://developers.klaviyo.com/en/reference/remove_profiles_from_list

The connector default API revision is 2026-04-15, matching the latest stable reference page on the access date. Request planning includes the required revision header, batches at up to 10,000 profiles, and enforces the documented 5 MB request payload ceiling through RETL request batching. List relationship requests batch at Klaviyo's documented 1,000 profile relationship objects per request.

Proof Level

Default tests provide:

1. Contract proof for package loading, connector metadata, surface shape, auth, and namespace-loadable config.
2. Translation proof for profile State upserts, list membership imports, and profile-ID list membership adds/removes without network access.
3. Mocked transport proof for request rendering, auth placement, response classification, redacted diagnostics, transport failure handling, selected request-plan reuse, and dry-run behavior.

Sandbox

Live sandbox tests are opt-in:

source local/env/.env.klaviyo.sandbox
make test-sandbox-klaviyo

The sandbox env file must provide DESTINATIONS__KLAVIYO__PRIVATE_API_KEY. The profile and list_memberships sandbox tests submit synthetic Bulk Profile Import jobs for lanacooper735@outlook.com. The list sandbox test creates a temporary managed list, resolves the generated Klaviyo profile ID by email, adds and removes that profile through list_memberships_by_profile_id, and deletes the temporary list. Default repository checks exclude live_sandbox tests and do not contact Klaviyo.