#include <fastmm/venues/feed.hpp>
template<class G>
const OrderCommand& cmd,
std::int64_t now_ms,
std::span<char> out,
std::string_view json,
std::int64_t rx_ts,
std::int64_t now_ns) {
{ g.encode(cmd, now_ms, out) } -> std::same_as<std::size_t>;
{ g.on_message(json, rx_ts) } -> std::same_as<ParseStatus>;
{ g.can_send(now_ns) } -> std::same_as<bool>;
}