Practical overview
When it fits
Use DoppelBot when a Slack workspace wants replies generated in the style of one selected user's messages, or when a developer wants a documented Modal-based starting point for that workflow.
Who it is for
- Slack workspaces that want a bot to draft replies modeled on one selected member's communication style.
- Developers who want to deploy or adapt the Python Slack application on Modal.
Documented uses
- Choose a Slack user as the style target and start model training with `/doppel `.
- Check whether the training process has finished by repeating the command.
- Summon the trained bot by mentioning it in a public Slack channel.
- Deploy the application using a Slack app, Modal credentials and the repository's documented configuration.
Requirements & limits
- A workspace can select only one target user, and the selection cannot be changed after installation.
- Training duration is described as a few minutes to an hour, depending on how prolific the selected user is on Slack.
- For the installed-app workflow, the README says Modal retains training states but not the Slack messages used for training.
- The repository is public and carries an MIT license.
Check current requirements in the official documentation. Source-based guidance does not mean OpenViST has run or independently tested this project.
Install and use DoppelBot in a Slack workspace
Select one workspace user for training, check training status, then summon the bot in a public channel.
Before you start
- A Slack workspace where the app can be installed.
Steps
Install DoppelBot in the Slack workspace using the app installation link.
In a channel, run
/doppelusing the target person's Slack handle or real name.Wait for training to finish; run the command again to check its status.
Mention the bot in a public channel to summon it.
Expected outcome
A Slack bot that generates replies in the selected user's style.
Guide limitations
- Each workspace is limited to one target user, and the choice cannot be changed after installation.
- Training time varies from a few minutes to an hour depending on how prolific the target user is on Slack.
Deploy a single-workspace instance on Modal
Set up and deploy the repository's Slack app for one workspace.
Before you start
- A Modal account, Python environment with the Modal client installed, and Modal token configured.
- A Slack app in the target workspace with the documented bot-token scopes.
- A Modal Slack secret containing
SLACK_SIGNING_SECRETandSLACK_BOT_TOKEN.
Steps
Create the Modal account, install the
modalclient in the Python environment, and configure a token withmodal setup.Create a Slack app and add the documented bot-token scopes:
app_mentions:read,channels:history,channels:join,channels:read,chat:write,chat:write.customize,commands,users.profile:read, andusers:read; install it to the workspace.Create a Modal Slack secret named
slack-finetune-secretwith the Slack signing secret underSLACK_SIGNING_SECRETand bot OAuth token underSLACK_BOT_TOKEN.From the repository root, run
modal deploy src.bot; use the printed URL for Slack Event Subscriptions and the/doppelslash command, then install the app to the workspace.
Expected outcome
A deployed Modal app connected to a Slack app for a single workspace.
Guide limitations
- This deployment path covers one workspace; multi-workspace distribution requires additional configuration and a Neon database.
Sources & review
Source record details
- Source availability
- Active
- Sources checked
- 13 October 2026
- Original website title
- modal-labs/doppel-bot · Official homepage title · retained in its source language

