ss-keel-devpanel

ss-keel-devpanel is the official observability addon for Keel. It embeds a real-time UI directly in your Go binary to inspect HTTP requests, logs, addon events, registered routes, and runtime configuration — with zero external dependencies.

Current stable release: v1.10.0 (2026-04-22)

Browse this addon

• Overview
• Installation
• Configuration
• Examples

Installation

keel add devpanel

Or manually:

go get github.com/slice-soft/ss-keel-devpanel

Bootstrap

When you run keel add devpanel, the CLI creates cmd/setup_devpanel.go and injects one line into cmd/main.go:

// cmd/setup_devpanel.go — created by keel add devpanel
package main

import (
    "github.com/slice-soft/ss-keel-core/config"
    "github.com/slice-soft/ss-keel-core/core"
    "github.com/slice-soft/ss-keel-devpanel/devpanel"
)

// setupDevPanel mounts the real-time observability panel on the Fiber app.
// Set panel.enabled=false in production to disable the panel.
func setupDevPanel(app *core.App) *devpanel.DevPanel {
    panelConfig := config.MustLoadConfig[devpanel.Config]()
    panel := devpanel.New(panelConfig)
    fiberApp := app.Fiber()
    fiberApp.Use(panel.RequestMiddleware())
    fiberApp.Use(panel.GlobalGuard())
    panel.Mount(fiberApp)
    return panel
}

The following is injected into cmd/main.go:

panel := setupDevPanel(app)
defer panel.Shutdown()

The required environment variables are added to .env:

KEEL_PANEL_ENABLED=true
KEEL_PANEL_SECRET=
KEEL_PANEL_PATH=/keel/panel

Open http://localhost:7331/keel/panel in your browser once the server is running.

Configuration

panel := devpanel.New(devpanel.Config{
    Enabled: true,             // set false in production
    Secret:  "strong-token",   // optional Bearer token
    Path:    "/keel/panel",    // default path prefix
})

Field	Type	Default	Description
Enabled	bool	true	Enable the panel. Set false in production.
Secret	string	""	Bearer token. Empty = no authentication.
Path	string	/keel/panel	URL prefix for all panel routes.

Panel pages

Requests

Captures the last 256 HTTP requests with method, path, status code, latency, and request ID. Panel routes are excluded automatically.

Logs

Captures the last 512 log entries written via PanelLogger. New entries stream live to connected browsers over SSE. Use WithRequestID to correlate log entries with a specific request:

logger := panel.Logger()

app.Use(func(c *fiber.Ctx) error {
    reqLogger := logger.WithRequestID(c.Get("X-Request-ID"))
    c.Locals("logger", reqLogger)
    return c.Next()
})

// In a handler:
log := c.Locals("logger").(*devpanel.PanelLogger)
log.Info("user fetched: %s", userID)

Routes

Lists all Fiber routes registered on the application at a glance.

Addons

Shows all addons that have self-registered with the panel. Any addon implementing contracts.Debuggable streams its PanelEvents() live:

// In your addon's Register step:
func (a *MyAddon) Register(app *keel.App) error {
    if panel, ok := app.GetAddon("devpanel").(contracts.PanelRegistry); ok {
        panel.RegisterAddon(a)
    }
    return nil
}

Addons that also implement contracts.Manifestable expose version, capabilities, and resources in the detail view.

Config

Displays all env vars declared by the panel and each registered Manifestable addon, Go runtime stats (goroutines, heap, sys), and addon manifests. Secret env var values are automatically redacted.

Security

• Always disable in production — set KEEL_PANEL_ENABLED=false.
• Use a secret — set KEEL_PANEL_SECRET to a strong random token and serve over HTTPS when the panel is enabled.
• GlobalGuard() provides defence-in-depth at the app middleware level: any request whose path starts with Config.Path receives a 404 immediately when the panel is disabled.
• Every panel response includes the X-Keel-Panel: true header.
• Rate limiting: 120 requests per minute per IP on all panel endpoints.