> ## Documentation Index
> Fetch the complete documentation index at: https://docs.maesn.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Changelog

> Product updates and announcements for the Maesn API

<Update label="April 2026">
  ## New asynchronous endpoints

  We released new [asynchronous](async-task) versions of two endpoints, so that you can post your data to DATEV without concerns about refresh token race conditions or rate-limits

  * [POST /files/async](api-reference/accounting-endpoints/files/upload-file-async)
  * [POST /expenses/async](api-reference/accounting-endpoints/expenses/create-expense-async)

  ## Signed authentication callbacks

  We implemented signed authentication callbacks, so that you can be certain that your callbacks originate from your platform and not a malicious actor.
  More details [here](authentication#signed-callbacks)

  ## New endpoints:

  ### Exact Online

  * [POST /bookingProposals (type INVOICE\_CREDIT\_NOTE)](api-reference/accounting-endpoints/bookingproposals/create-booking-proposal)

  ### Buchhaltungsbutler

  * [GET /bills](api-reference/accounting-endpoints/bills/get-bills)
  * [GET /bills/:id](api-reference/accounting-endpoints/bills/get-bill)
  * [GET /bookingProposals](api-reference/accounting-endpoints/bookingproposals/get-booking-proposals)
  * [GET /bookingProposals/:id](api-reference/accounting-endpoints/bookingproposals/get-booking-proposal)

  ### sevdesk

  * [GET /bills](api-reference/accounting-endpoints/bills/get-bills)
  * [GET /bills/:id](api-reference/accounting-endpoints/bills/get-bill)
  * [GET /bookingProposals](api-reference/accounting-endpoints/bookingproposals/get-booking-proposals)
  * [GET /bookingProposals/:id](api-reference/accounting-endpoints/bookingproposals/get-booking-proposal)
</Update>