diff --git a/README.md b/README.md
index ae4cbe5d..6ce40dd3 100644
--- a/README.md
+++ b/README.md
@@ -103,6 +103,7 @@ gemini extensions install https://github.com/ix-infrastructure/ix-gemini-plugin
 ## Requirements
 
 - macOS, Linux, or Windows
+- Node.js 20 or newer
 - Git installed
 - Docker (for full functionality)
 
diff --git a/ix-cli/package.json b/ix-cli/package.json
index 35b3bdf3..b4de1cab 100644
--- a/ix-cli/package.json
+++ b/ix-cli/package.json
@@ -12,6 +12,9 @@
   "bin": {
     "ix": "dist/cli/main.js"
   },
+  "engines": {
+    "node": ">=20.0.0"
+  },
   "scripts": {
     "build": "node scripts/build-core-ingestion.mjs && node -e \"require('fs').rmSync('dist',{recursive:true,force:true})\" && tsc",
     "test": "node scripts/build-core-ingestion.mjs && vitest run --exclude test/parser.test.ts && node test/parser.smoke.mjs",
diff --git a/ix-cli/src/cli/commands/map.ts b/ix-cli/src/cli/commands/map.ts
index bc2f648b..6dff0703 100644
--- a/ix-cli/src/cli/commands/map.ts
+++ b/ix-cli/src/cli/commands/map.ts
@@ -5,6 +5,7 @@ import { IxClient } from "../../client/api.js";
 import { getEndpoint } from "../config.js";
 import { roundFloat } from "../format.js";
 import { bootstrap } from "../bootstrap.js";
+import { formatFetchError } from "../errors.js";
 import { ingestFiles } from "./ingest.js";
 
 export interface MapRegion {
@@ -159,7 +160,7 @@ Examples:
           mapMode: true,
         });
       } catch (err: any) {
-        console.error(chalk.red("Error:"), err.message ?? err);
+        console.error(chalk.red("Error:"), formatFetchError(err));
         process.exitCode = 1;
         return;
       }
@@ -183,7 +184,7 @@ Examples:
         result = await client.map({ full: opts.full }) as MapResult;
       } catch (err: any) {
         if (mapInterval) { clearInterval(mapInterval); process.stderr.write('\r' + ' '.repeat(60) + '\r'); }
-        console.error(chalk.red("Error:"), err.message ?? err);
+        console.error(chalk.red("Error:"), formatFetchError(err));
         process.exitCode = 1;
         return;
       }
diff --git a/ix-cli/src/cli/errors.ts b/ix-cli/src/cli/errors.ts
index 5d73eddc..9889ce16 100644
--- a/ix-cli/src/cli/errors.ts
+++ b/ix-cli/src/cli/errors.ts
@@ -70,6 +70,39 @@ export class CliResolutionError extends Error {
   }
 }
 
+/**
+ * Format an error for display, unwrapping fetch `TypeError: fetch failed`
+ * to expose the underlying transport cause (e.g. ECONNRESET, UND_ERR_SOCKET).
+ *
+ * Node's built-in fetch (undici) throws `TypeError('fetch failed')` on any
+ * transport-level failure and stashes the real error in `err.cause`. Without
+ * this unwrap, users see a bare "fetch failed" with no actionable detail —
+ * see the Node 18 EOL / undici 5.x transport-drop bug report.
+ */
+export function formatFetchError(err: unknown): string {
+  if (err === null || err === undefined) return String(err);
+  const e = err as { message?: unknown; cause?: unknown };
+  const base = typeof e.message === "string" && e.message.length > 0
+    ? e.message
+    : String(err);
+
+  if (base.toLowerCase().includes("fetch failed") && e.cause) {
+    const cause = e.cause as { code?: unknown; message?: unknown };
+    const parts: string[] = [];
+    if (typeof cause.code === "string" && cause.code.length > 0) {
+      parts.push(cause.code);
+    }
+    if (typeof cause.message === "string" && cause.message.length > 0) {
+      parts.push(cause.message);
+    } else if (parts.length === 0) {
+      parts.push(String(e.cause));
+    }
+    return `${base} (${parts.join(": ")})`;
+  }
+
+  return base;
+}
+
 export function renderCliError(err: unknown, debug = false): void {
   if (err instanceof CliUsageError || err instanceof CliResolutionError) {
     process.stderr.write(chalk.red(`Error: ${err.message}\n`));
diff --git a/ix-cli/src/cli/main.ts b/ix-cli/src/cli/main.ts
index b8415758..56481f57 100644
--- a/ix-cli/src/cli/main.ts
+++ b/ix-cli/src/cli/main.ts
@@ -9,6 +9,22 @@ import { readFileSync } from "fs";
 import { join, dirname } from "path";
 import { fileURLToPath } from "url";
 
+// Runtime Node version guard. Runs before any command work so users on an
+// unsupported Node get an actionable message instead of a cryptic "fetch
+// failed" deep inside undici.
+const MIN_NODE_MAJOR = 20;
+{
+  const current = process.versions.node;
+  const major = parseInt(current.split(".")[0] ?? "0", 10);
+  if (!Number.isFinite(major) || major < MIN_NODE_MAJOR) {
+    process.stderr.write(
+      `Ix requires Node.js ${MIN_NODE_MAJOR} or newer. You are running v${current}.\n` +
+      `Install a supported version from https://nodejs.org/ and re-run.\n`
+    );
+    process.exit(1);
+  }
+}
+
 let cliVersion = "0.0.0";
 try {
   const __dirname = dirname(fileURLToPath(import.meta.url));
diff --git a/requirements.txt b/requirements.txt
index 5e5d8513..a341cd2e 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -29,11 +29,11 @@ git>=2
 #  STEP 1: Node.js (auto-installed/upgraded if missing or too old)
 # ============================================================================
 
-# Node.js >= 18 (installer targets Node 22 LTS)
+# Node.js >= 20 (installer targets Node 22 LTS)
 #   macOS:   brew install node OR official .pkg installer
 #   Linux:   NodeSource apt/dnf/yum repo (setup_22.x) OR apk
 #   Windows: manual from https://nodejs.org/
-node>=18
+node>=20
 npm>=8  # bundled with Node.js
 
 # ============================================================================
diff --git a/scripts/build-cli.sh b/scripts/build-cli.sh
index e1a46adb..a1ab8f5c 100755
--- a/scripts/build-cli.sh
+++ b/scripts/build-cli.sh
@@ -20,13 +20,13 @@ CLI_DIR="$IX_DIR/ix-cli"
 check_prerequisites() {
   if ! command -v node &> /dev/null; then
     echo "Error: Node.js is not installed."
-    echo "  Install: https://nodejs.org/ (v18+ required)"
+    echo "  Install: https://nodejs.org/ (v20+ required)"
     exit 1
   fi
 
   NODE_VERSION=$(node -v | sed 's/v//' | cut -d. -f1)
-  if [ "$NODE_VERSION" -lt 18 ]; then
-    echo "Error: Node.js 18+ required (found $(node -v))"
+  if [ "$NODE_VERSION" -lt 20 ]; then
+    echo "Error: Node.js 20+ required (found $(node -v))"
     exit 1
   fi
 
diff --git a/scripts/dev/setup.sh b/scripts/dev/setup.sh
index 92d85113..4a9796d6 100755
--- a/scripts/dev/setup.sh
+++ b/scripts/dev/setup.sh
@@ -129,7 +129,7 @@ if [ "${#MISSING_DEPS[@]}" -gt 0 ]; then
   for dep in "${MISSING_DEPS[@]}"; do
     case "$dep" in
       docker) echo "    docker:  https://docs.docker.com/get-docker/" ;;
-      node)   echo "    node:    https://nodejs.org (v18+ required)" ;;
+      node)   echo "    node:    https://nodejs.org (v20+ required)" ;;
     esac
   done
   echo ""
diff --git a/scripts/install/install.ps1 b/scripts/install/install.ps1
index bd1172e6..c964dab7 100644
--- a/scripts/install/install.ps1
+++ b/scripts/install/install.ps1
@@ -27,7 +27,7 @@ $IxBin = "$IxHome\bin"
 $ComposeDir = "$IxHome\backend"
 $HealthUrl = "http://localhost:8090/v1/health"
 $ArangoUrl = "http://localhost:8529/_api/version"
-$NodeMinMajor = 18
+$NodeMinMajor = 20
 
 # ── Helpers ──────────────────────────────────────────────────────────────────
 
diff --git a/scripts/install/install.sh b/scripts/install/install.sh
index 1d90f2e1..f632e1f3 100755
--- a/scripts/install/install.sh
+++ b/scripts/install/install.sh
@@ -28,7 +28,7 @@ COMPOSE_DIR="$IX_HOME/backend"
 HEALTH_URL="http://localhost:8090/v1/health"
 ARANGO_URL="http://localhost:8529/_api/version"
 
-NODE_MIN_MAJOR=18
+NODE_MIN_MAJOR=20
 
 # -- Windows / POSIX docker compose wrapper --