Ship Your Slack Integration In Minutes, Not Months
Stop building a Slack app just to post a message. Zernio gives you one endpoint to schedule Slack messages and answer DMs and mentions, while we own the OAuth, the Events API server, and the token rotation.
No credit card required
{
"platforms": ["slack"],
"accountId": "acc_abc123",
"content": "Hello from Zernio!",
"scheduledFor": "2025-01-15T19:00:00Z"
}Why Zernio vs the Slack Web API?
Zernio API
- ✓Simple API key - start in 30 seconds
- ✓Automatic retries & queue management
- ✓Attach files to a post, we handle the upload
- ✓We run the Events API endpoint for you
- ✓One API for 16 platforms
Slack Web API Direct
- ✗Create a Slack app, manage scopes, handle re-auth on every scope change
- ✗Per-method rate limit tiers with your own backoff logic
- ✗Separate multi-step upload flow for files
- ✗Host an Events API endpoint with signature verification and 3s acks
- ✗Build separate integrations per platform
Save 3-5 weeks of development. Ship your Slack integration today, not next quarter.
You Don't Build a Slack App - We Provide It
No Developer Portal setup, no Events API server to host, no signing secrets or token rotation to get right. Install the Zernio app into your workspace with one OAuth click and pick the channel it publishes to.
Public channels are joined automatically. For a private channel, run /invite @Zernio first.
Content Types
How It Works
- 1.Get Your API KeySign up and grab your API key. Takes 30 seconds.
- 2.Add Zernio to SlackOne OAuth click from Settings -> Connections, then pick the channel to publish to.
- 3.Schedule or AutomateOne API call to schedule a message. Incoming DMs and mentions fire a webhook.
Features
Ship Faster
Go from zero to a scheduled Slack message in under a minute. No Slack app review, no bot process to keep alive.
Real Scheduling
Slack cannot schedule messages sent by an app. Zernio queues yours and publishes at the exact timestamp, in your timezone.
One API, All Platforms
The same call that posts to Slack posts to Instagram, LinkedIn and the rest. Build once, announce everywhere.
Code Example
// Schedule a message to a connected Slack channel
const response = await fetch('https://zernio.com/api/v1/posts', {
method: 'POST',
headers: {
'Authorization': 'Bearer YOUR_API_KEY',
'Content-Type': 'application/json'
},
body: JSON.stringify({
platforms: [{
platform: 'slack',
accountId: 'your-slack-account-id'
}],
content: 'Release 2.3 is live :rocket:',
scheduledFor: '2026-08-03T09:00:00Z'
})
});
const data = await response.json();
console.log('Slack post id:', data.id);Common Questions
- Do I need to create my own Slack app?
- └No. Zernio provides the Slack app. You install it through OAuth and choose which channel it may post to. There is no Developer Portal setup, no bot hosting, and no tokens for you to manage.
- Do I need to be a Slack admin?
- └Usually not, though some workspaces require admin approval for any new app. If yours does, Slack shows a request-approval screen and an admin has to allow it before the connection completes.
- Can it post to private channels?
- └Yes, but a member must run /invite @Zernio in the private channel first - an app cannot add itself to a private channel. Public channels are joined automatically when you connect them.
- Can one connection post to several channels?
- └Each connection publishes to a single channel, so it is always obvious where a scheduled message lands. Connecting another channel in the same workspace does not require going through OAuth again.
- Does Zernio read everything in my channels?
- └No. Only direct messages to the app, messages that @-mention it, and replies in threads it is already part of reach your inbox. Ordinary conversation in a connected channel is never ingested, and there is no backfill of history from before you connected.
- Can I build an agent that answers in Slack?
- └Yes. Every incoming message fires a webhook that tells you whether the app was mentioned and whether the message is a thread reply. Your agent decides what to say and posts the answer back through the API, in thread.
- Do I get analytics for Slack messages?
- └No. Slack has no public analytics API for message engagement, so Slack posts report zero in Zernio. Reactions and replies stay visible inside Slack.
One API, 16 Platforms
Learn More
Ready to Ship Your Slack Integration?
Schedule messages, upload files, and answer DMs and mentions from one inbox. Same reliability, 10x less code.
