diff --git a/README.rst b/README.rst
index 9790956..196ba58 100644
--- a/README.rst
+++ b/README.rst
@@ -231,7 +231,7 @@ A sample config file:
 
     repo: datalad/datalad
     vars:
-      path_prefix: '{year}//{month}//{day}/{ci}/{type}/{type_id}/{commit[:7]}'
+      path_prefix: '{year}//{month}//{day}/{ci}/{type}/{type_id}/{build_commit[:7]}'
     ci:
       github:
         path: '{path_prefix}/{wf_name}/{number}/logs/'
@@ -295,8 +295,17 @@ Placeholder          Definition
                      is the name of the branch to which the push was made (or
                      possibly the tag that was pushed, if using Appveyor); for
                      ``release``, this is the name of the tag
-``{commit}``         The hash of the commit the build ran against or that was
-                     tagged for the release
+``{build_commit}``   The hash of the commit the build ran against or that was
+                     tagged for the release.  Note that, for PR builds on
+                     Travis and Appveyor, this is the hash of an autogenerated
+                     merge commit.
+``{commit}``         The hash of the original commit that triggered the build
+                     or that was tagged for the release.  For GitHub Actions
+                     and all non-pull request builds, this is always the same
+                     as ``{build_commit}``.  For pull request builds on
+                     Appveyor, this is the head of the PR branch.  For pull
+                     request builds on Travis, this is ``UNK``, as the API does
+                     not expose the original commit.
 ``{number}``         The run number of the workflow run (GitHub) or the build
                      number (Travis and Appveyor) [1]_
 ``{status}``         The success status of the workflow run (GitHub) or job
diff --git a/src/tinuous/__main__.py b/src/tinuous/__main__.py
index 52f8a11..99be784 100644
--- a/src/tinuous/__main__.py
+++ b/src/tinuous/__main__.py
@@ -141,7 +141,8 @@ class Asset(ABC, BaseModel):
     created_at: datetime
     event_type: EventType
     event_id: str
-    commit: str
+    build_commit: str
+    commit: Optional[str]
     number: int
     status: str
 
@@ -151,6 +152,7 @@ class Config:
 
     def path_fields(self) -> Dict[str, str]:
         utc_date = self.created_at.astimezone(timezone.utc)
+        commit = "UNK" if self.commit is None else self.commit
         return {
             "year": utc_date.strftime("%Y"),
             "month": utc_date.strftime("%m"),
@@ -160,7 +162,8 @@ def path_fields(self) -> Dict[str, str]:
             "second": utc_date.strftime("%S"),
             "type": self.event_type.value,
             "type_id": self.event_id,
-            "commit": self.commit,
+            "build_commit": self.build_commit,
+            "commit": commit,
             "number": str(self.number),
             "status": self.status,
             "common_status": COMMON_STATUS_MAP[self.status],
@@ -386,6 +389,7 @@ def from_workflow_run(
             created_at=ensure_aware(run.created_at),
             event_type=event_type,
             event_id=event_id,
+            build_commit=run.head_sha,
             commit=run.head_sha,
             workflow_name=workflow.name,
             workflow_file=workflow.path.split("/")[-1],
@@ -451,6 +455,7 @@ def from_workflow_run(
             created_at=ensure_aware(run.created_at),
             event_type=event_type,
             event_id=event_id,
+            build_commit=run.head_sha,
             commit=run.head_sha,
             workflow_name=workflow.name,
             workflow_file=workflow.path.split("/")[-1],
@@ -523,6 +528,7 @@ def path_fields(self) -> Dict[str, str]:
             "ci": "github",
             "type": "release",
             "type_id": self.tag_name,
+            "build_commit": self.commit,
             "commit": self.commit,
         }
 
@@ -649,12 +655,16 @@ def from_job(
         if event is None:
             raise ValueError(f"Build has unknown event type {build['event_type']!r}")
         event_id: str
+        commit: Optional[str]
         if event is EventType.CRON:
             event_id = created_at.strftime("%Y%m%dT%H%M%S")
+            commit = build["commit"]["sha"]
         elif event is EventType.PUSH:
             event_id = build["branch"]["name"]
+            commit = build["commit"]["sha"]
         elif event is EventType.PULL_REQUEST:
             event_id = str(build["pull_request_number"])
+            commit = None
         else:
             raise AssertionError(f"Unhandled EventType: {event!r}")
         return cls(
@@ -662,7 +672,8 @@ def from_job(
             created_at=created_at,
             event_type=event,
             event_id=event_id,
-            commit=build["commit"]["sha"],
+            build_commit=build["commit"]["sha"],
+            commit=commit,
             number=int(build["number"]),
             job=removeprefix(job["number"], f"{build['number']}."),
             job_id=job["id"],
@@ -783,15 +794,18 @@ def from_job(
         if build.get("pullRequestId"):
             event = EventType.PULL_REQUEST
             event_id = build["pullRequestId"]
+            commit = build["pullRequestHeadCommitId"]
         else:
             event = EventType.PUSH
             event_id = build["branch"]
+            commit = build["commitId"]
         return cls(
             client=client,
             created_at=created_at,
             event_type=event,
             event_id=event_id,
-            commit=build["commitId"],
+            build_commit=build["commitId"],
+            commit=commit,
             number=build["buildNumber"],
             job=job["jobId"],
             status=job["status"],