Visma and Paychex integration

What moves between them

Worker data flows from Paychex into Visma. When Paychex sends a worker demographic, compensation, or employment status change event, ml-connector fetches the full worker record and syncs employee name, status, hire date, termination date, job title, location, and cost center into Visma's employee and dimension records. Job and organization data from Paychex are matched to corresponding dimensions in Visma so payroll allocations land on valid cost centers. The sync is one-directional: Paychex is the source, Visma the destination.

How ml-connector handles it

ml-connector stores both OAuth2 credential sets encrypted and obtains bearer tokens from each system before each API call. On the Paychex side, it registers for WRKR_DEM, WRKR_CMP, WRKR_EMPL, WRKR_ADD, and CLT_ACCESS webhooks and listens for events; when a notification arrives, it fetches the full worker record from GET /workers/{id} to ensure all fields are current. On the Visma side, it upserts employee records via PUT to the employee endpoint, using the ETag value in the If-Match header for optimistic locking, and maps Paychex job titles and organizations to Visma dimensions by name. Since Paychex does not send refresh tokens, ml-connector checks token expiry before each call and proactively acquires a new token rather than waiting for a 401. Since Visma webhooks have no guaranteed retry, ml-connector also polls the employee and dimension endpoints periodically to catch any changes missed by webhooks. All worker records carry an audit trail with timestamps and change reasons.

A real-world example

A mid-sized Nordic manufacturing company runs Visma for general ledger, purchasing, and financial close, and Paychex Flex for payroll across multiple plants and headquarters. Before the integration, the HR team exported employee rosters from Paychex each month and re-entered new hires, terminations, and job changes into Visma by hand, and payroll coordinators manually verified that cost centers in Paychex matched cost centers in Visma before running payroll. With Paychex and Visma connected, each hire, termination, and job change flows into Visma automatically, cost centers are aligned by the integration, and the finance team starts month-end close with accurate headcount and cost allocation ready for review.

What you can do

• •Sync Paychex workers, job titles, and organizations into Visma employee records and dimensions as changes occur.
• •Keep Visma cost centers and organizational dimensions aligned with Paychex jobs and locations so payroll allocations land on the correct GL accounts.
• •Listen for Paychex worker demographic, compensation, and employment status changes via webhooks and fetch full current state on each event.
• •Bridge OAuth2 authentication on both sides and proactively refresh Paychex tokens before expiry since no refresh token is issued.
• •Poll Visma employee and dimension endpoints periodically to catch changes missed by Visma webhooks, which have no automatic retry guarantee.

Questions

Does ml-connector sync payroll GL postings from Paychex into Visma?

No. ml-connector syncs employee records, job titles, and organizational dimensions from Paychex into Visma to keep headcount and cost allocations current. Paychex does not expose GL postings or financial transactions through its developer API, so payroll journal entries are not part of this integration.

How does ml-connector handle Paychex webhook notification-only payloads?

Paychex webhooks notify that a change occurred but do not include the changed data in the payload. ml-connector receives the notification and immediately calls the Paychex GET /workers/{id} endpoint to fetch the full current state of the worker, then syncs the complete record into Visma.

Why does ml-connector poll Visma if webhooks are available?

Visma webhooks are sent once with no automatic retry if the receiver is unavailable, so they can be lost if ml-connector is temporarily down. ml-connector registers for webhooks but also polls the employee and dimension endpoints periodically to ensure no changes are missed, guaranteeing eventual consistency.