Replit Deploy Integration
Overview
Deploy applications on Replit's hosting platform. Three deployment types: Static (free, frontend-only), Autoscale (scales to zero, pay per request), and Reserved VM (always-on, fixed cost). Includes custom domain setup, health checks, rollbacks, and deployment monitoring.
Prerequisites
- Replit Core, Pro, or Teams plan (deployment access)
- Application working in Workspace ("Run" button)
- Custom domain (optional) with DNS access
Deployment Types
| Type | Best For | Pricing | Scale |
|---|
| Static | HTML/CSS/JS frontends | Free | CDN-backed, auto-cached |
| Autoscale | Variable traffic APIs | Per request | 0 to N instances |
| Reserved VM | Always-on services | $0.20+/day | Fixed resources |
Instructions
Step 1: Configure .replit for Deployment
entrypoint = "src/index.ts"
run = "npx tsx src/index.ts"
[nix]
channel = "stable-24_05"
[env]
NODE_ENV = "production"
[deployment]
run = ["sh", "-c", "npx tsx src/index.ts"]
build = ["sh", "-c", "npm ci --production && npm run build"]
deploymentTarget = "autoscale"
Reserved VM:
[deployment]
run = ["sh", "-c", "node dist/index.js"]
build = ["sh", "-c", "npm ci && npm run build"]
deploymentTarget = "cloudrun"
Static:
[deployment]
deploymentTarget = "static"
publicDir = "dist"
build = ["sh", "-c", "npm ci && npm run build"]
Step 2: Configure Secrets for Production
Workspace Secrets auto-sync to Deployments (2025+).
1. Click lock icon (Secrets) in sidebar
2. Add production secrets:
- DATABASE_URL (auto-populated by Replit PostgreSQL)
- API_KEY, JWT_SECRET, etc.
3. Verify in Deployment Settings > Environment Variables
Step 3: Add Health Check Endpoint
Replit monitors your deployment via health checks. Always include one:
import { Router } from 'express';
import { pool } from '../services/db';
const router = Router();
router.get('/health', async (req, res) => {
const checks: Record<string, any> = {
status: 'ok',
uptime: process.uptime(),
timestamp: new Date().toISOString(),
};
if (process.env.DATABASE_URL) {
try {
await pool.query('SELECT 1');
checks.database = 'connected';
} catch {
checks.database = 'disconnected';
checks.status = 'degraded';
}
}
checks.repl = process.env.REPL_SLUG;
checks.region = process.env.REPLIT_DEPLOYMENT_REGION;
const statusCode = checks.status === ? : ;
res.(statusCode).(checks);
});
router;
Step 4: Deploy
Via Replit UI:
1. Click "Deploy" button in the top bar
2. Select deployment type:
- Static: for frontend-only apps
- Autoscale: scales to zero when idle
- Reserved VM: always-on, choose machine size
3. Configure machine size (Autoscale/VM):
- 0.25 vCPU / 512 MB — lightweight APIs
- 0.5 vCPU / 1 GB — standard web apps
- 2 vCPU / 4 GB — compute-heavy apps
- 4+ vCPU / 8-16 GB — production workloads
4. Click "Deploy"
5. Monitor build output in the deploy console
Step 5: Custom Domain Setup
1. Go to Deployment Settings > Custom Domain
2. Enter your domain: app.example.com
3. Add DNS record at your registrar:
Type: CNAME
Name: app
Value: your-repl-slug.replit.app
4. Wait for SSL auto-provisioning (1-5 minutes)
5. Verify:
dig app.example.com CNAME
curl -I https://app.example.com
curl -sf https://app.example.com/health | jq .
For Replit-purchased domains:
- DNS managed in Replit dashboard
- MX records supported for custom email
- SSL auto-provisioned
Step 6: Deployment Rollback
Replit supports one-click rollback to any previous successful deployment.
1. Go to Deployment Settings > History
2. View list of past deployments with timestamps
3. Click "Rollback" on the desired version
4. Deployment reverts immediately
5. Verify health endpoint after rollback
Step 7: Post-Deploy Verification
set -euo pipefail
DEPLOY_URL="https://your-app.replit.app"
echo "=== Deployment Verification ==="
echo -n "Health: "
curl -sf "$DEPLOY_URL/health" | jq -r '.status'
echo -n "Response time: "
curl -s -o /dev/null -w "%{time_total}s\n" "$DEPLOY_URL/"
echo -n "SSL: "
curl -sI "$DEPLOY_URL" | grep -i "strict-transport" && echo "OK" || echo "Missing HSTS"
echo "Cold start test: wait 10 min, then curl again"
Error Handling
| Issue | Cause | Solution |
|---|
| Deploy fails at build | Dependency error | Test npm ci && npm run build locally first |
| 503 after deploy | App crashes on start | Check deployment logs, verify secrets |
| Port mismatch | Not using PORT env | app.listen(process.env.PORT || 3000) |
| Cold start slow (>10s) | Heavy imports on startup | Lazy-load non-critical modules |
| Custom domain 404 | DNS not propagated | Wait, or verify CNAME record |
| SSL not provisioning | Wrong DNS record | Must be CNAME to .replit.app |
Resources
Next Steps
For multi-environment setup, see replit-multi-env-setup.
