diff --git a/src/plugins/github/example/example-github.json b/src/plugins/github/example/example-github.json
index 4c53a2f..3e7f88d 100644
--- a/src/plugins/github/example/example-github.json
+++ b/src/plugins/github/example/example-github.json
@@ -10,6 +10,7 @@
                 "date": "2018-09-12T19:48:21-07:00",
                 "user": null
             },
+            "authoredDate": "2018-09-13T02:48:21Z",
             "id": "MDY6Q29tbWl0MTIzMjU1MDA2OjZiZDFiNGMwYjcxOWMyMmM2ODhhNzQ4NjNiZTA3YTY5OWI3YjliMzQ=",
             "message": "A commit from someone with no GitHub account\n\nSummary:\nThis is a commit to master by a user with email at `example.com`, which\nshould not be linked to any GitHub account.\n\nGenerated with:\n\n    git -c user.name='Mysterious Stranger' \\\n        -c user.email='mysterious-stranger@example.com' \\\n        commit -S\n\nActually committed and signed by William Chargin <wchargin@gmail.com>.\nVerify public key at either of:\n  - <https://github.com/wchargin.gpg>\n  - <https://wchargin.github.io/> (click link to \"My PGP key\")",
             "oid": "6bd1b4c0b719c22c688a74863be07a699b7b9b34",
@@ -25,6 +26,7 @@
                             "url": "https://github.com/credbot"
                         }
                     },
+                    "authoredDate": "2018-09-12T21:43:54Z",
                     "id": "MDY6Q29tbWl0MTIzMjU1MDA2OmM0MzBiZDc0NDU1MTA1Zjc3MjE1ZWNlNTE5NDUwOTRjZWVlZTZjODY=",
                     "message": "Hello from credbot!\n\nSummary:\nThis is a commit to master under the name and email of credbot, who has\nno other contributions to the repository. This is intended to test that\nwe can still pull the correct GitHub user off of the commit.\n\nGenerated with:\n\n    git -c user.name='credbot' \\\n        -c user.email='42819382+credbot@users.noreply.github.com' \\\n        commit\n\nActually committed and signed by William Chargin <wchargin@gmail.com>.\nVerify public key at either of:\n  - <https://github.com/wchargin.gpg>\n  - <https://wchargin.github.io/> (click link to \"My PGP key\")",
                     "oid": "c430bd74455105f77215ece51945094ceeee6c86",
@@ -40,6 +42,7 @@
                                     "url": "https://github.com/decentralion"
                                 }
                             },
+                            "authoredDate": "2018-03-01T04:25:54Z",
                             "id": "MDY6Q29tbWl0MTIzMjU1MDA2OjZkNWIzYWEzMWViYjY4YTA2Y2ViNDZiYmQ2Y2Y0OWI2Y2NkNmY1ZTY=",
                             "message": "This pull request will be more contentious. I can feel it... (#5)\n\n* This pull request will be more contentious. I can feel it...\r\n\r\n* Address wchargin's unreasonable complaints",
                             "oid": "6d5b3aa31ebb68a06ceb46bbd6cf49b6ccd6f5e6",
@@ -55,6 +58,7 @@
                                             "url": "https://github.com/decentralion"
                                         }
                                     },
+                                    "authoredDate": "2018-02-28T08:43:47Z",
                                     "id": "MDY6Q29tbWl0MTIzMjU1MDA2OjBhMjIzMzQ2YjRlNmRlYzAxMjdiMWU2YWE4OTJjNGVlMDQyNGI2NmE=",
                                     "message": "Merge pull request #3 from sourcecred/add-readme\n\nAdd README, merge via PR.",
                                     "oid": "0a223346b4e6dec0127b1e6aa892c4ee0424b66a",
@@ -70,6 +74,7 @@
                                                     "url": "https://github.com/decentralion"
                                                 }
                                             },
+                                            "authoredDate": "2018-02-28T08:41:11Z",
                                             "id": "MDY6Q29tbWl0MTIzMjU1MDA2OmVjOTFhZGI3MThhNjA0NWI0OTIzMDNmMDBkOGU4YmViOTU3ZGM3ODA=",
                                             "message": "Commit without pull request.",
                                             "oid": "ec91adb718a6045b492303f00d8e8beb957dc780",
@@ -88,6 +93,7 @@
                                                     "url": "https://github.com/decentralion"
                                                 }
                                             },
+                                            "authoredDate": "2018-02-28T08:42:09Z",
                                             "id": "MDY6Q29tbWl0MTIzMjU1MDA2OmVjYzg4OWRjOTRjZjZkYTE3YWU2ZWFiNWJiN2I3MTU1ZjU3NzUxOWQ=",
                                             "message": "Add README, merge via PR.",
                                             "oid": "ecc889dc94cf6da17ae6eab5bb7b7155f577519d",
@@ -103,6 +109,7 @@
                                                             "url": "https://github.com/decentralion"
                                                         }
                                                     },
+                                                    "authoredDate": "2018-02-28T08:41:11Z",
                                                     "id": "MDY6Q29tbWl0MTIzMjU1MDA2OmVjOTFhZGI3MThhNjA0NWI0OTIzMDNmMDBkOGU4YmViOTU3ZGM3ODA=",
                                                     "message": "Commit without pull request.",
                                                     "oid": "ec91adb718a6045b492303f00d8e8beb957dc780",
@@ -763,6 +770,7 @@
                         "url": "https://github.com/decentralion"
                     }
                 },
+                "authoredDate": "2018-02-28T08:43:47Z",
                 "id": "MDY6Q29tbWl0MTIzMjU1MDA2OjBhMjIzMzQ2YjRlNmRlYzAxMjdiMWU2YWE4OTJjNGVlMDQyNGI2NmE=",
                 "message": "Merge pull request #3 from sourcecred/add-readme\n\nAdd README, merge via PR.",
                 "oid": "0a223346b4e6dec0127b1e6aa892c4ee0424b66a",
@@ -778,6 +786,7 @@
                                 "url": "https://github.com/decentralion"
                             }
                         },
+                        "authoredDate": "2018-02-28T08:41:11Z",
                         "id": "MDY6Q29tbWl0MTIzMjU1MDA2OmVjOTFhZGI3MThhNjA0NWI0OTIzMDNmMDBkOGU4YmViOTU3ZGM3ODA=",
                         "message": "Commit without pull request.",
                         "oid": "ec91adb718a6045b492303f00d8e8beb957dc780",
@@ -796,6 +805,7 @@
                                 "url": "https://github.com/decentralion"
                             }
                         },
+                        "authoredDate": "2018-02-28T08:42:09Z",
                         "id": "MDY6Q29tbWl0MTIzMjU1MDA2OmVjYzg4OWRjOTRjZjZkYTE3YWU2ZWFiNWJiN2I3MTU1ZjU3NzUxOWQ=",
                         "message": "Add README, merge via PR.",
                         "oid": "ecc889dc94cf6da17ae6eab5bb7b7155f577519d",
@@ -811,6 +821,7 @@
                                         "url": "https://github.com/decentralion"
                                     }
                                 },
+                                "authoredDate": "2018-02-28T08:41:11Z",
                                 "id": "MDY6Q29tbWl0MTIzMjU1MDA2OmVjOTFhZGI3MThhNjA0NWI0OTIzMDNmMDBkOGU4YmViOTU3ZGM3ODA=",
                                 "message": "Commit without pull request.",
                                 "oid": "ec91adb718a6045b492303f00d8e8beb957dc780",
@@ -895,6 +906,7 @@
                         "url": "https://github.com/decentralion"
                     }
                 },
+                "authoredDate": "2018-03-01T04:25:54Z",
                 "id": "MDY6Q29tbWl0MTIzMjU1MDA2OjZkNWIzYWEzMWViYjY4YTA2Y2ViNDZiYmQ2Y2Y0OWI2Y2NkNmY1ZTY=",
                 "message": "This pull request will be more contentious. I can feel it... (#5)\n\n* This pull request will be more contentious. I can feel it...\r\n\r\n* Address wchargin's unreasonable complaints",
                 "oid": "6d5b3aa31ebb68a06ceb46bbd6cf49b6ccd6f5e6",
@@ -910,6 +922,7 @@
                                 "url": "https://github.com/decentralion"
                             }
                         },
+                        "authoredDate": "2018-02-28T08:43:47Z",
                         "id": "MDY6Q29tbWl0MTIzMjU1MDA2OjBhMjIzMzQ2YjRlNmRlYzAxMjdiMWU2YWE4OTJjNGVlMDQyNGI2NmE=",
                         "message": "Merge pull request #3 from sourcecred/add-readme\n\nAdd README, merge via PR.",
                         "oid": "0a223346b4e6dec0127b1e6aa892c4ee0424b66a",
@@ -925,6 +938,7 @@
                                         "url": "https://github.com/decentralion"
                                     }
                                 },
+                                "authoredDate": "2018-02-28T08:41:11Z",
                                 "id": "MDY6Q29tbWl0MTIzMjU1MDA2OmVjOTFhZGI3MThhNjA0NWI0OTIzMDNmMDBkOGU4YmViOTU3ZGM3ODA=",
                                 "message": "Commit without pull request.",
                                 "oid": "ec91adb718a6045b492303f00d8e8beb957dc780",
@@ -943,6 +957,7 @@
                                         "url": "https://github.com/decentralion"
                                     }
                                 },
+                                "authoredDate": "2018-02-28T08:42:09Z",
                                 "id": "MDY6Q29tbWl0MTIzMjU1MDA2OmVjYzg4OWRjOTRjZjZkYTE3YWU2ZWFiNWJiN2I3MTU1ZjU3NzUxOWQ=",
                                 "message": "Add README, merge via PR.",
                                 "oid": "ecc889dc94cf6da17ae6eab5bb7b7155f577519d",
@@ -958,6 +973,7 @@
                                                 "url": "https://github.com/decentralion"
                                             }
                                         },
+                                        "authoredDate": "2018-02-28T08:41:11Z",
                                         "id": "MDY6Q29tbWl0MTIzMjU1MDA2OmVjOTFhZGI3MThhNjA0NWI0OTIzMDNmMDBkOGU4YmViOTU3ZGM3ODA=",
                                         "message": "Commit without pull request.",
                                         "oid": "ec91adb718a6045b492303f00d8e8beb957dc780",
diff --git a/src/plugins/github/graphqlTypes.js b/src/plugins/github/graphqlTypes.js
index a52a89f..a89618b 100644
--- a/src/plugins/github/graphqlTypes.js
+++ b/src/plugins/github/graphqlTypes.js
@@ -23,6 +23,7 @@ export type Commit = {|
     +date: null | GitTimestamp,
     +user: null | User,
   |},
+  +authoredDate: GitTimestamp,
   +id: string,
   +message: String,
   +oid: GitObjectID,
diff --git a/src/plugins/github/schema.js b/src/plugins/github/schema.js
index 384d431..6a38f86 100644
--- a/src/plugins/github/schema.js
+++ b/src/plugins/github/schema.js
@@ -117,6 +117,10 @@ export default function schema(): Schema.Schema {
         user: s.node("User"),
       }),
       parents: s.connection("Commit"),
+      // In contrast to the author.date, this is both nonNull and is
+      // specifically the authoredDate. Docs for author.date suggest that
+      // field might be the commiter date instead.
+      authoredDate: s.primitive(s.nonNull("GitTimestamp")),
     }),
     Tag: s.object({
       id: s.id(),