pull-freezed pull stream that applies Object.freeze() recursively install npm install pull-freezed example var pull = require('pull-stream');var freeze = require('pull-freezed'); pull( pull.values( [ { a: 'immutable' } ] ), freeze, pull.map(function (data) { data.a = 'something'; return data; }), pull.collect(function (err, result) { if (!err) console.log(result); // a === 'immutable' }));