diff --git a/plugins/ultraplan-local/.claude-plugin/plugin.json b/plugins/ultraplan-local/.claude-plugin/plugin.json
index 340bce2..3b62d17 100644
--- a/plugins/ultraplan-local/.claude-plugin/plugin.json
+++ b/plugins/ultraplan-local/.claude-plugin/plugin.json
@@ -1,12 +1,12 @@
 {
-  "name": "ultraplan-local",
-  "description": "Six-command context-engineering pipeline (brief → research → plan → execute → review → continue) with project folders, specialized agent swarms, external research triangulation, adversarial review, post-hoc independent review with Handover 6 feedback loop, multi-session resumption, session decomposition, and headless execution.",
-  "version": "3.4.1",
+  "name": "voyage",
+  "description": "Voyage — brief, research, plan, execute, review, continue. Contract-driven Claude Code pipeline.",
+  "version": "4.0.0",
   "author": {
     "name": "Kjell Tore Guttormsen"
   },
   "homepage": "https://git.fromaitochitta.com/open/ultraplan-local",
   "repository": "https://git.fromaitochitta.com/open/ultraplan-local.git",
   "license": "MIT",
-  "keywords": ["planning", "implementation", "research", "context-engineering", "agents", "adversarial-review", "headless", "execution"]
+  "keywords": ["voyage", "trek", "planning", "implementation", "research", "context-engineering", "agents", "adversarial-review", "headless", "execution"]
 }
diff --git a/plugins/ultraplan-local/CHANGELOG.md b/plugins/ultraplan-local/CHANGELOG.md
index 2693f00..941abea 100644
--- a/plugins/ultraplan-local/CHANGELOG.md
+++ b/plugins/ultraplan-local/CHANGELOG.md
@@ -4,6 +4,37 @@ All notable changes to this project will be documented in this file.
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
 
+## v4.0.0 — 2026-05-05
+
+**Breaking. Rebrand. No migration path.**
+
+The `ultraplan-local` plugin is renamed to **Voyage**. All seven commands
+are renamed from `/ultra*-local` to `/trek*`:
+
+- `/ultrabrief-local` → `/trekbrief`
+- `/ultraresearch-local` → `/trekresearch`
+- `/ultraplan-local` → `/trekplan`
+- `/ultraexecute-local` → `/trekexecute`
+- `/ultrareview-local` → `/trekreview`
+- `/ultracontinue-local` → `/trekcontinue`
+- `/ultraplan-end-session-local` → `/trekendsession`
+
+Internal renames: FLAG_SCHEMA keys, stats filenames, env vars, branch
+namespace, type discriminators, hook stderr prefixes, settings.json scope
+keys all updated to `trek*` form. Plugin identity is now `voyage`.
+
+No backward compatibility. Old artifacts on user disks are orphaned.
+Fork-and-own users re-fork from main if they want to follow upstream;
+there is no migration helper.
+
+See `TRADEMARKS.md` for the new trademark hygiene notice clarifying
+independence from Anthropic.
+
+Out-of-scope handoff (operator follow-up): plugin directory rename
+`plugins/ultraplan-local/` → `plugins/voyage/`, marketplace-root
+coordination across `../../README.md`, `../../CLAUDE.md`, and
+`../../.claude-plugin/marketplace.json`.
+
 ## [3.4.1] - 2026-05-04 — `/ultracontinue-local` hot-fix + ultra-cc-architect doc-rydding
 
 Forward-patch on top of v3.4.0. Fixes four bugs in the multi-session
diff --git a/plugins/ultraplan-local/package.json b/plugins/ultraplan-local/package.json
index 150cd2a..410413f 100644
--- a/plugins/ultraplan-local/package.json
+++ b/plugins/ultraplan-local/package.json
@@ -1,7 +1,7 @@
 {
-  "name": "ultraplan-local",
-  "version": "3.4.1",
-  "description": "Six-command context-engineering pipeline (brief → research → plan → execute → review → continue) for Claude Code.",
+  "name": "voyage",
+  "version": "4.0.0",
+  "description": "Voyage — brief, research, plan, execute, review, continue. Contract-driven Claude Code pipeline.",
   "type": "module",
   "engines": {
     "node": ">=18"