Made a simple connector to push high-severity items to Slack.

We've been using CrowdStrike Falcon for a while, and while the console is great, our on-call engineers needed faster, more contextual alerts for critical items—things that need immediate human review. The default email notifications were getting lost.

I built a lightweight connector using Falcon's APIs and a small Go service. It filters for high-severity detections (`severity >= 80`) and pushes a formatted, actionable message to a dedicated Slack channel. This gives the team immediate visibility without console-juggling.

Here's the core logic of the filter and the Slack message construction. It runs in a simple Kubernetes pod, triggered by a cron schedule to poll the API.

```go
// Simplified filter logic
func filterHighSeverity(detections []Detection) []Detection {
var highSeverity []Detection
for _, d := range detections {
if d.Severity >= 80 && d.Status == "new" {
highSeverity = append(highSeverity, d)
}
}
return highSeverity
}

// Slack block builder (using Slack's Block Kit)
func buildSlackBlock(d Detection) slack.Block {
fields := []*slack.TextBlockObject{
{Type: "mrkdwn", Text: fmt.Sprintf("*Host:*n%s", d.Hostname)},
{Type: "mrkdwn", Text: fmt.Sprintf("*Severity:*n%d", d.Severity)},
{Type: "mrkdwn", Text: fmt.Sprintf("*Technique:*n%s", d.Technique)},
}
return slack.NewSectionBlock(nil, fields, nil)
}
```

Key design choices:
* **Stateless:** The service queries for `new` detections only, relying on Falcon's API filters. State management is left to CrowdStrike.
* **Idempotent:** Runs every 5 minutes; duplicate alerts are de-duplicated by the detection ID within Slack's own system.
* **Minimal IAM:** The service uses a principle with read-only access to detections, following least privilege.

The result has cut our mean time to acknowledge (MTTA) for critical detections significantly. The main pitfall to watch is API rate limiting—implementing exponential backoff and respecting the `X-RateLimit-Reset` header is crucial. For teams already in Slack, this simple bridge creates a much tighter feedback loop.