from typing import List
from typing import Dict


def group_by_author(commits: List[dict]) -> Dict[str, List[dict]]:
    """Group GitHub commit objects by their author."""
    grouped: Dict[str, List[dict]] = {}
    for commit in commits:
        name = commit["author"]["login"]
        if name not in grouped:
            grouped[name] = []
        grouped[name].append(commit)
    return grouped