From observing comments here on HN, it’s clear that it’s fairly common for non-native speakers of English to use “by foo” when “with foo” or “from foo” would be

From observing comments here on HN, it’s clear that it’s fairly common for non-native speakers of English to use “by foo” when “with foo” or “from foo” would be more appropriate. From this and the fact that OP wrote “by Legos” and not “by LEGO”, it was simple to deduce that they meant that it was created using little interlocking plastic pieces and not by the company well-known for selling little interlocking plastic pieces.