diff --git a/publish/src/subcommands/check.ts b/publish/src/subcommands/check.ts
new file mode 100644
index 0000000..3c5f77f
--- /dev/null
+++ b/publish/src/subcommands/check.ts
@@ -0,0 +1,65 @@
+import type { Config } from '../core/config.ts'
+import { createBunkerSigner } from '../core/signer.ts'
+import { loadOutbox } from '../core/outbox.ts'
+import { loadBlossomServers } from '../core/blossom-list.ts'
+
+export interface CheckResult {
+  ok: boolean
+  issues: string[]
+}
+
+export async function runCheck(config: Config): Promise<CheckResult> {
+  const issues: string[] = []
+
+  try {
+    const signer = await createBunkerSigner(config.bunkerUrl)
+    const pk = await signer.getPublicKey()
+    if (pk !== config.authorPubkeyHex) {
+      issues.push(
+        `bunker-pubkey (${pk}) matcht AUTHOR_PUBKEY_HEX (${config.authorPubkeyHex}) nicht`,
+      )
+    }
+  } catch (err) {
+    issues.push(`bunker-ping fehlgeschlagen: ${err instanceof Error ? err.message : err}`)
+  }
+
+  try {
+    const outbox = await loadOutbox(config.bootstrapRelay, config.authorPubkeyHex)
+    if (outbox.write.length === 0) {
+      issues.push('kind:10002 hat keine write-relays — publiziere zuerst ein gültiges Event')
+    }
+  } catch (err) {
+    issues.push(`kind:10002 laden: ${err instanceof Error ? err.message : err}`)
+  }
+
+  try {
+    const servers = await loadBlossomServers(config.bootstrapRelay, config.authorPubkeyHex)
+    if (servers.length === 0) {
+      issues.push('kind:10063 hat keine server — publiziere zuerst ein gültiges Event')
+    } else {
+      for (const server of servers) {
+        try {
+          const resp = await fetch(server + '/', { method: 'HEAD' })
+          if (!resp.ok && resp.status !== 405) {
+            issues.push(`blossom-server ${server}: HTTP ${resp.status}`)
+          }
+        } catch (err) {
+          issues.push(`blossom-server ${server}: ${err instanceof Error ? err.message : err}`)
+        }
+      }
+    }
+  } catch (err) {
+    issues.push(`kind:10063 laden: ${err instanceof Error ? err.message : err}`)
+  }
+
+  return { ok: issues.length === 0, issues }
+}
+
+export function printCheckResult(result: CheckResult): void {
+  if (result.ok) {
+    console.log('✓ pre-flight ok')
+    return
+  }
+  console.error('✗ pre-flight issues:')
+  for (const i of result.issues) console.error(`  - ${i}`)
+}