diff --git a/package.json b/package.json
index 0ad85f4..4abfa89 100644
--- a/package.json
+++ b/package.json
@@ -31,6 +31,7 @@
     "tslint": "tslint 'src/**/*.{js,jsx,ts,tsx}' -t verbose --project .",
     "clean": "rimraf lib es6 es2019 es2020 esm typedocs coverage gh-pages yarn-error.log",
     "build": "tsc --project tsconfig.build.json --module commonjs",
+    "build:commands": "ts-node scripts/build-commands.ts",
     "jest": "node -r ts-node/register ./node_modules/.bin/jest",
     "test": "jest --maxWorkers 7",
     "coverage": "yarn test --collectCoverage",
@@ -55,7 +56,8 @@
     "tslib": "^2.6.2",
     "tslint": "^6.1.3",
     "tslint-config-common": "^1.6.2",
-    "typescript": "^5.3.3"
+    "typescript": "^5.3.3",
+    "commands": "https://github.com/streamich/commands#4321d5d40473c48fadf49fd99662032eac9b855b"
   },
   "jest": {
     "verbose": true,
diff --git a/scripts/build-commands.ts b/scripts/build-commands.ts
new file mode 100644
index 0000000..38c59f1
--- /dev/null
+++ b/scripts/build-commands.ts
@@ -0,0 +1,24 @@
+import * as fs from 'fs';
+const defs = require('commands/lib/commands.json');
+
+let ts = `// This file is generated by "yarn build:commands".
+
+// Set of commands that are writable.
+export const write = new Set<string>([
+`;
+
+const commands = Object.keys(defs);
+for (const command of commands) {
+  const cmd = command.toUpperCase();
+  const def = defs[command];
+  const isWritable = Array.isArray(def.flags) && def.flags.includes('write');
+  if (isWritable) ts += `  '${cmd}',\n`;
+}
+ts += `]);
+`;
+
+const dir = 'src/generated';
+fs.mkdirSync(dir, {recursive: true});
+const filename = dir + '/commands.ts';
+fs.writeFileSync(filename, ts);
+console.log('Wrote', filename);
diff --git a/src/generated/commands.ts b/src/generated/commands.ts
new file mode 100644
index 0000000..57983f9
--- /dev/null
+++ b/src/generated/commands.ts
@@ -0,0 +1,104 @@
+// This file is generated by "yarn build:commands".
+
+// Set of commands that are writable.
+export const write = new Set<string>([
+  'APPEND',
+  'BITFIELD',
+  'BITOP',
+  'BLMOVE',
+  'BLMPOP',
+  'BLPOP',
+  'BRPOP',
+  'BRPOPLPUSH',
+  'BZMPOP',
+  'BZPOPMAX',
+  'BZPOPMIN',
+  'COPY',
+  'DECR',
+  'DECRBY',
+  'DEL',
+  'EXPIRE',
+  'EXPIREAT',
+  'FLUSHALL',
+  'FLUSHDB',
+  'GEOADD',
+  'GEORADIUS',
+  'GEORADIUSBYMEMBER',
+  'GEOSEARCHSTORE',
+  'GETDEL',
+  'GETEX',
+  'GETSET',
+  'HDEL',
+  'HINCRBY',
+  'HINCRBYFLOAT',
+  'HMSET',
+  'HSET',
+  'HSETNX',
+  'INCR',
+  'INCRBY',
+  'INCRBYFLOAT',
+  'LINSERT',
+  'LMOVE',
+  'LMPOP',
+  'LPOP',
+  'LPUSH',
+  'LPUSHX',
+  'LREM',
+  'LSET',
+  'LTRIM',
+  'MIGRATE',
+  'MOVE',
+  'MSET',
+  'MSETNX',
+  'PERSIST',
+  'PEXPIRE',
+  'PEXPIREAT',
+  'PFADD',
+  'PFDEBUG',
+  'PFMERGE',
+  'PSETEX',
+  'RENAME',
+  'RENAMENX',
+  'RESTORE',
+  'RESTORE-ASKING',
+  'RPOP',
+  'RPOPLPUSH',
+  'RPUSH',
+  'RPUSHX',
+  'SADD',
+  'SDIFFSTORE',
+  'SET',
+  'SETBIT',
+  'SETEX',
+  'SETNX',
+  'SETRANGE',
+  'SINTERSTORE',
+  'SMOVE',
+  'SORT',
+  'SPOP',
+  'SREM',
+  'SUNIONSTORE',
+  'SWAPDB',
+  'UNLINK',
+  'XACK',
+  'XADD',
+  'XAUTOCLAIM',
+  'XCLAIM',
+  'XDEL',
+  'XREADGROUP',
+  'XSETID',
+  'XTRIM',
+  'ZADD',
+  'ZDIFFSTORE',
+  'ZINCRBY',
+  'ZINTERSTORE',
+  'ZMPOP',
+  'ZPOPMAX',
+  'ZPOPMIN',
+  'ZRANGESTORE',
+  'ZREM',
+  'ZREMRANGEBYLEX',
+  'ZREMRANGEBYRANK',
+  'ZREMRANGEBYSCORE',
+  'ZUNIONSTORE',
+]);
diff --git a/yarn.lock b/yarn.lock
index b578365..8c22c96 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1024,6 +1024,10 @@ commander@^2.12.1:
   resolved "https://registry.yarnpkg.com/commander/-/commander-2.20.3.tgz#fd485e84c03eb4881c20722ba48035e8531aeb33"
   integrity sha512-GpVkmM8vF2vQUkj2LvZmD35JxeJOLCwJ9cUkugyk2nuhbv3+mJvpLYYt+0+USMxE+oj+ey/lJEnhZw75x/OMcQ==
 
+"commands@https://github.com/streamich/commands#4321d5d40473c48fadf49fd99662032eac9b855b":
+  version "0.2.0"
+  resolved "https://github.com/streamich/commands#4321d5d40473c48fadf49fd99662032eac9b855b"
+
 concat-map@0.0.1:
   version "0.0.1"
   resolved "https://registry.yarnpkg.com/concat-map/-/concat-map-0.0.1.tgz#d8a96bd77fd68df7793a73036a3ba0d5405d477b"