Thank you. For serverless-webpack@^3.0.0 and webpack@^3.0.0 you should change it as follows:

// webpack.conf.js

const BundleAnalyzerPlugin = require('webpack-bundle-analyzer').BundleAnalyzerPlugin;
const slsw = require('serverless-webpack');
const webpack = require('webpack');
const path = require('path');

// You can access the options given to serverles with "slsw.lib.options" and
// the serverless instance with "slsw.lib.serverless". This allows you to dynamically
// build the configuration depending on anything available in serverless (e.g.
// the service definition (slsw.lib.serverless.service.xxxxx)

module.exports = {
    entry: slsw.lib.entries,
    target: 'node',
    module: {
      rules: [
        {
          test: /\.ts(x?)$/,
          use: [
            { loader: 'ts-loader' }
          ]
        },
        {
          test: /\.json$/,
          use: [
            { loader: 'json' }
          ]
        },
        {
          test: /\.sql$/,
          use: [
            { loader: 'raw-loader' }
          ]
        },
        {
          test: /\.(md|jst|def)$/,
          use: [
            { loader: 'ignore-loader' }
          ]
        },
      ]
    },
    resolve: {
        extensions: ['.ts', '.js', '.tsx', '.jsx', '.json', '']
    },
    output: {
        libraryTarget: 'commonjs',
        path: path.join(__dirname, '.webpack'),
        filename: '[name].js',
        comments: false
    },
    plugins: [
        new webpack.optimize.DedupePlugin(),
        new BundleAnalyzerPlugin({
            analyzerMode: 'static',
            reportFilename: 'report.html',
            generateStatsFile: true,
            statsFilename: 'stats.json',
            logLevel: 'info',
            openAnalyzer: false
        })
    ]
};

This entries setting also allows you to use individual packaging together with the plugin, so that each function is optimized and compiled separately. Additionally, it now works with serverless invoke local.

Thanks @cmwhited for reporting 👍 Could you share the serverless.yml you are using so that we can try to reproduce it?