diff --git a/build.ts b/build.ts
index 5a2ad896e..745866950 100644
--- a/build.ts
+++ b/build.ts
@@ -1,6 +1,6 @@
 import { readdir, readFile, writeFile, cp, unlink, mkdir } from 'fs/promises'
 import { join } from 'path'
-import { getMacroDefines } from './scripts/defines.ts'
+import { getMacroDefines, DEFAULT_BUILD_FEATURES } from './scripts/defines.ts'
 
 const outdir = 'dist'
 
@@ -23,44 +23,8 @@ if (process.env.SKIP_REVIEW_BUILTIN) {
   }
 }
 
-// Default features that match the official CLI build.
+// Feature flags imported from defines.ts (single source of truth).
 // Additional features can be enabled via FEATURE_<NAME>=1 env vars.
-const DEFAULT_BUILD_FEATURES = [
-  'AGENT_TRIGGERS_REMOTE',
-  'CHICAGO_MCP',
-  'VOICE_MODE',
-  'SHOT_STATS',
-  'PROMPT_CACHE_BREAK_DETECTION',
-  'TOKEN_BUDGET',
-  // P0: local features
-  'AGENT_TRIGGERS',
-  'ULTRATHINK',
-  'BUILTIN_EXPLORE_PLAN_AGENTS',
-  'LODESTONE',
-  // P1: API-dependent features
-  'EXTRACT_MEMORIES',
-  'VERIFICATION_AGENT',
-  'KAIROS_BRIEF',
-  'AWAY_SUMMARY',
-  'ULTRAPLAN',
-  // P2: daemon + remote control server
-  'DAEMON',
-  // PR-package restored features
-  'WORKFLOW_SCRIPTS',
-  'HISTORY_SNIP',
-  'CONTEXT_COLLAPSE',
-  'MONITOR_TOOL',
-  'FORK_SUBAGENT',
-//   'UDS_INBOX',
-  'KAIROS',
-  'COORDINATOR_MODE',
-  'LAN_PIPES',
-  // 'REVIEW_ARTIFACT', // API 请求无响应，需进一步排查 schema 兼容性
-  // P3: poor mode (disable extract_memories + prompt_suggestion)
-  'POOR',
-  // P3: serve mode (HTTP API server)
-  'DIRECT_CONNECT',
-]
 
 // Collect FEATURE_* env vars → Bun.build features
 const envFeatures = Object.keys(process.env)
diff --git a/scripts/defines.ts b/scripts/defines.ts
index c03657405..aaea5f6db 100644
--- a/scripts/defines.ts
+++ b/scripts/defines.ts
@@ -58,7 +58,7 @@ export const DEFAULT_BUILD_FEATURES = [
     'ACP',                         // ACP 代理协议，支持外部 agent 接入
     'WORKFLOW_SCRIPTS',            // 工作流脚本（.claude/workflows/ 中的 YAML/MD）
     'HISTORY_SNIP',                // 历史消息裁剪，压缩上下文窗口
-    'CONTEXT_COLLAPSE',            // 上下文折叠，自动压缩旧消息
+    // 'CONTEXT_COLLAPSE',            // 已禁用：实现是空壳 stub，启用后会抑制 auto compact 导致上下文管理完全失效
     'MONITOR_TOOL',                // Monitor 工具，流式监控后台进程输出
     // 'FORK_SUBAGENT',               // Fork 子代理，显式 `fork: true` 参数触发，不影响 run_in_background 行为
     // 'UDS_INBOX',                   // inbox 数组只增不减（非 GB 级主因）
diff --git a/scripts/dev.ts b/scripts/dev.ts
index 39d258284..7a54af2ba 100644
--- a/scripts/dev.ts
+++ b/scripts/dev.ts
@@ -6,7 +6,7 @@
  */
 import { join, dirname } from "node:path";
 import { fileURLToPath } from "node:url";
-import { getMacroDefines } from "./defines.ts";
+import { getMacroDefines, DEFAULT_BUILD_FEATURES as DEFAULT_FEATURES } from "./defines.ts";
 
 // Resolve project root from this script's location
 const __filename = fileURLToPath(import.meta.url);
@@ -22,37 +22,7 @@ const defineArgs = Object.entries(defines).flatMap(([k, v]) => [
 ]);
 
 // Bun --feature flags: enable feature() gates at runtime.
-// Default features enabled in dev mode.
-const DEFAULT_FEATURES = [
-  "BUDDY", "TRANSCRIPT_CLASSIFIER", "BRIDGE_MODE",
-  "AGENT_TRIGGERS_REMOTE", "CHICAGO_MCP", "VOICE_MODE",
-  "SHOT_STATS", "PROMPT_CACHE_BREAK_DETECTION", "TOKEN_BUDGET",
-  // P0: local features
-  "AGENT_TRIGGERS",
-  "ULTRATHINK",
-  "BUILTIN_EXPLORE_PLAN_AGENTS",
-  "LODESTONE",
-  // P1: API-dependent features
-  "EXTRACT_MEMORIES", "VERIFICATION_AGENT",
-  "KAIROS_BRIEF", "AWAY_SUMMARY", "ULTRAPLAN",
-  // P2: daemon + remote control server
-  "DAEMON",
-  // PR-package restored features
-  "WORKFLOW_SCRIPTS",
-  "HISTORY_SNIP",
-  "CONTEXT_COLLAPSE",
-  "MONITOR_TOOL",
-  "FORK_SUBAGENT",
-  "UDS_INBOX",
-  "KAIROS",
-  "COORDINATOR_MODE",
-  "LAN_PIPES",
-  // "REVIEW_ARTIFACT", // API 请求无响应，需进一步排查 schema 兼容性
-  // P3: poor mode (disable extract_memories + prompt_suggestion)
-  "POOR",
-  // P3: serve mode (HTTP API server)
-  "DIRECT_CONNECT",
-];
+// Default features imported from defines.ts (single source of truth).
 
 // Any env var matching FEATURE_<NAME>=1 will also enable that feature.
 // e.g. FEATURE_PROACTIVE=1 bun run dev