README.md in pg_ha_migrations-1.3.0 vs README.md in pg_ha_migrations-1.4.0

@@ -146,10 +146,12 @@
 safe_change_column_default :table, :column, -> { "NOW()" }
 # Functional expression evaluated at migration time:
 safe_change_column_default :table, :column, -> { "'NOW()'" }
 ```
 
+Note: On Postgres 11+ adding a column with a constant default value does not rewrite or scan the table (under a lock or otherwise). In that case a migration adding a column with a default should do so in a single operation rather than the two-step `safe_add_column` followed by `safe_change_column_default`. We enforce this best practice with the error `PgHaMigrations::BestPracticeError`, but if your prefer otherwise (or are running in a mixed Postgres version environment), you may opt out by setting `config.prefer_single_step_column_addition_with_default = true` [in your configuration initializer](#configuration).
+
 #### safe\_make\_column\_nullable
 
 Safely make the column nullable.
 
 ```ruby
@@ -270,10 +272,12 @@
 
 #### Available options
 
 - `disable_default_migration_methods`: If true, the default implementations of DDL changes in `ActiveRecord::Migration` and the PostgreSQL adapter will be overridden by implementations that raise a `PgHaMigrations::UnsafeMigrationError`. Default: `true`
 - `check_for_dependent_objects`: If true, some `unsafe_*` migration methods will raise a `PgHaMigrations::UnsafeMigrationError` if any dependent objects exist. Default: `false`
+- `prefer_single_step_column_addition_with_default`: If `true`, raise an error when adding a column and separately setting a constant default value for that column in the same migration. Default: `false`
+- 'allow_force_create_table`: If false, the `force: true` option to ActiveRecord's `create_table` method is disallowed. Default: `true`
 
 ### Rake Tasks
 
 Use this to check for blocking transactions before migrating.
 
@@ -297,10 +301,14 @@
 
 After checking out the repo, run `bin/setup` to install dependencies and start a postgres docker container. Then, run `bundle exec rspec` to run the tests. You can also run `bin/console` for an interactive prompt that will allow you to experiment. This project uses Appraisal to test against multiple versions of ActiveRecord; you can run the tests against all supported version with `bundle exec appraisal rspec`.
 
 Running tests will automatically create a test database in the locally running Postgres server. You can find the connection parameters in `spec/spec_helper.rb`, but setting the environment variables `PGHOST`, `PGPORT`, `PGUSER`, and `PGPASSWORD` will override the defaults.
 
-To install this gem onto your local machine, run `bundle exec rake install`. To release a new version, update the version number in `version.rb`, and then run `bundle exec rake release`, which will create a git tag for the version, push git commits and tags, and push the `.gem` file to [rubygems.org](https://rubygems.org).
+To install this gem onto your local machine, run `bundle exec rake install`.
+
+To release a new version, update the version number in `version.rb`, and then run `bundle exec rake release`, which will create a git tag for the version, push git commits and tags, and push the `.gem` file to [rubygems.org](https://rubygems.org).
+
+Note: if while releasing the gem you get the error `Your rubygems.org credentials aren't set. Run \`gem push\` to set them.` you can more simply run `gem signin`.
 
 ## Contributing
 
 Bug reports and pull requests are welcome on GitHub at https://github.com/braintreeps/pg_ha_migrations. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the [Contributor Covenant](http://contributor-covenant.org) code of conduct.