A key requirement for our implementation is that the integration is both seamless and secure. For this reason, we use the API token mechanism implemented by the rest-on-couch package . For this, AiiDAlab first checks if it already owns a suitable token to connect to the ELN and otherwise prompts the user to set up the connection, if that is not the case. To this aim, the user is asked to provide the ELN instance's address and type (cheminfo in our case) and the access token, which can be obtained via the "Request token" button within the AiiDAlab interface. A click on the button will open a page from the cheminfo ELN in an iframe. Before printing the token, the ELN first checks if the user is already authenticated and, if not, it redirects to the authentication page. After the authentication, the user is redirected back to the token-generation page, where the token is shown. This mechanism ensures that the browser contexts remain separated, but we can still use the existing session cookie stored in the browser to authenticate the session in the ELN. The separation of browser contexts also implies that users need to copy and paste the token from the iframe into an input field on the same page. At the same time, the reuse of the session cookie implies that users do not have to log in again typing username and password. The token will then be stored in the AiiDAlab file system of the user. We consider the security risk of that as acceptable, since the access to the AiiDAlab file system is already protected by the authentication mechanism of AiiDAlab.