Is my implementation against the builder pattern?

My sample code:

class CitiesListBuilder{
    private List<String> cities;

    public static CitiesListBuilder newBuilder(){
        return new CitiesListBuilder();
    }

    private CitiesListBuilder(){
        cities = new ArrayList<>();
    }

    public CitiesListBuilder addCity(String city) {
        cities.add(city);
        return this;
    }

    public CitiesListBuilder apply(Function<List<String>, List<String>> filter) {
        cities = cities.apply(filter);
        return this;
    }

    public List<String> build(){
        return cities;
    }
}

To use:

CitiesListBuilder.newBuilder
       .addCity("LA")
       .addCity("NY")
       .apply(NorthCitiesFilterFunction) 
       .build();

I understand my code maybe a bad sample of using builder pattern, but to me it makes the code shorter and more clear (my own opinions), and I don't see any problem with concurrent issue.

But to your opinions, what will be the arguments if I should/should not do the code likes this?

Thank you.