gistfile1.txt

record Column {
    bytes name;
    bytes value;
    long timestamp;
    union { int, null } ttl;
}

// becomes...

record Column {
    bytes name;
    bytes value;
    Timestamp timestamp;
    Timestamp ttl;

    /* deprecated */
    long @aliases(["timestamp"]) deprecated_timestamp;
    union { int, null } @aliases(["ttl"]) deprecated_ttl;
}