diff --git a/DESCRIPTION b/DESCRIPTION
index f605866..eea8950 100755
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,6 +1,6 @@
 Package: repometrics
 Title: Metrics for Your Code Repository
-Version: 0.1.1.018
+Version: 0.1.1.026
 Authors@R: 
     person("Mark", "Padgham", , "mark.padgham@email.com", role = c("aut", "cre"),
            comment = c(ORCID = "0000-0003-2172-5265"))
@@ -16,6 +16,7 @@ Imports:
     dplyr,
     fs,
     gert,
+    git2r,
     httr2,
     memoise,
     pbapply,
diff --git a/R/chaoss-external.R b/R/chaoss-external.R
index 8a77d93..2f0a6ea 100644
--- a/R/chaoss-external.R
+++ b/R/chaoss-external.R
@@ -39,6 +39,7 @@ has_gh_ci_tests <- function (path) {
 #' is defined as, "Percentage of new code commits linked with change requests
 #' in the last 90 days."
 #' \url{https://chaoss.community/kb/metrics-model-collaboration-development-index/}.
+#' @noRd
 prop_commits_in_change_req <- function (path, end_date = Sys.Date ()) {
 
     or <- org_repo_from_path (path)
diff --git a/R/cm-data-git.R b/R/cm-data-git.R
new file mode 100644
index 0000000..c491f0e
--- /dev/null
+++ b/R/cm-data-git.R
@@ -0,0 +1,52 @@
+cm_data_gitlog_internal <- function (path) {
+
+    cmt <- git2r::commits (repo = path)
+
+    hash <- vapply (cmt, function (i) i$sha, character (1L))
+    aut_name <- vapply (cmt, function (i) i$author$name, character (1L))
+    aut_email <- vapply (cmt, function (i) i$author$email, character (1L))
+    timestamp <- vapply (cmt, function (i) as.character (i$author$when), character (1L))
+    cmt_message <- vapply (cmt, function (i) i$message, character (1L))
+    cmt_message <- gsub ("\\n$", "", cmt_message)
+
+    stats <- lapply (
+        hash,
+        function (i) gert::git_commit_stats (ref = i, repo = path)
+    )
+
+    lines_added <- vapply (stats, function (i) i$insertions, integer (1L))
+    lines_removed <- vapply (stats, function (i) i$deletions, integer (1L))
+    nfiles_changed <- vapply (stats, function (i) i$files, integer (1L))
+
+    diffs <- lapply (
+        hash,
+        function (i) gert::git_diff (ref = i, repo = path)
+    )
+
+    files_changed <- lapply (diffs, function (i) i$new)
+
+    # bench::marking shows this form is quicker than either:
+    # `length (grep ("^(\\-|\\+)$", j))` or
+    # `length (which (j %in% c ("-", "+")))`.
+    whitespace <- vapply (diffs, function (i) {
+        patch_i <- suppressWarnings (strsplit (i$patch, "\\n"))
+        res <- vapply (patch_i, function (j) {
+            c (length (which (j == "+")), length (which (j == "-")))
+        }, integer (2L))
+        as.integer (rowSums (res))
+    }, integer (2L))
+
+    data.frame (
+        hash = hash,
+        aut_name = aut_name,
+        aut_email = aut_email,
+        timestamp = as.POSIXct (timestamp),
+        message = cmt_message,
+        nfiles_changed = nfiles_changed,
+        lines_added = lines_added,
+        lines_removed = lines_removed,
+        whitespace_added = whitespace [1, ],
+        whitespace_removed = whitespace [2, ]
+    )
+}
+cm_data_gitlog <- memoise::memoise (cm_data_gitlog_internal)
diff --git a/codemeta.json b/codemeta.json
index 0572622..afd0744 100644
--- a/codemeta.json
+++ b/codemeta.json
@@ -8,13 +8,13 @@
   "codeRepository": "https://github.com/ropensci-review-tools/repometrics",
   "issueTracker": "https://github.com/ropensci-review-tools/repometrics/issues",
   "license": "https://spdx.org/licenses/GPL-3.0",
-  "version": "0.1.1.018",
+  "version": "0.1.1.026",
   "programmingLanguage": {
     "@type": "ComputerLanguage",
     "name": "R",
     "url": "https://r-project.org"
   },
-  "runtimePlatform": "R version 4.4.1 (2024-06-14)",
+  "runtimePlatform": "R version 4.4.2 (2024-10-31)",
   "author": [
     {
       "@type": "Person",
@@ -182,6 +182,18 @@
       "sameAs": "https://CRAN.R-project.org/package=gert"
     },
     "6": {
+      "@type": "SoftwareApplication",
+      "identifier": "git2r",
+      "name": "git2r",
+      "provider": {
+        "@id": "https://cran.r-project.org",
+        "@type": "Organization",
+        "name": "Comprehensive R Archive Network (CRAN)",
+        "url": "https://cran.r-project.org"
+      },
+      "sameAs": "https://CRAN.R-project.org/package=git2r"
+    },
+    "7": {
       "@type": "SoftwareApplication",
       "identifier": "httr2",
       "name": "httr2",
@@ -193,7 +205,7 @@
       },
       "sameAs": "https://CRAN.R-project.org/package=httr2"
     },
-    "7": {
+    "8": {
       "@type": "SoftwareApplication",
       "identifier": "memoise",
       "name": "memoise",
@@ -205,7 +217,7 @@
       },
       "sameAs": "https://CRAN.R-project.org/package=memoise"
     },
-    "8": {
+    "9": {
       "@type": "SoftwareApplication",
       "identifier": "pbapply",
       "name": "pbapply",
@@ -217,7 +229,7 @@
       },
       "sameAs": "https://CRAN.R-project.org/package=pbapply"
     },
-    "9": {
+    "10": {
       "@type": "SoftwareApplication",
       "identifier": "pkgstats",
       "name": "pkgstats",
@@ -225,7 +237,7 @@
     },
     "SystemRequirements": {}
   },
-  "fileSize": "125.292KB",
+  "fileSize": "142.573KB",
   "readme": "https://github.com/ropensci-review-tools/repometrics/blob/main/README.md",
   "contIntegration": [
     "https://github.com/ropensci-review-tools/repometrics/actions?query=workflow%3AR-CMD-check",
diff --git a/tests/testthat/test-cm-data.R b/tests/testthat/test-cm-data.R
new file mode 100644
index 0000000..8363811
--- /dev/null
+++ b/tests/testthat/test-cm-data.R
@@ -0,0 +1,30 @@
+test_that ("cm data git", {
+
+    pkg <- system.file ("extdata", "testpkg.zip", package = "repometrics")
+    flist <- unzip (pkg, exdir = fs::path_temp ())
+    path <- fs::path_dir (flist [1])
+
+    log <- cm_data_gitlog (path)
+
+    expect_s3_class (log, "data.frame")
+    expect_equal (ncol (log), 10L)
+    nms <- c (
+        "hash", "aut_name", "aut_email", "timestamp", "message",
+        "nfiles_changed", "lines_added", "lines_removed", "whitespace_added",
+        "whitespace_removed"
+    )
+    expect_equal (names (log), nms)
+
+    char_nms <- nms [c (1:3, 5)]
+    int_nms <- nms [6:10]
+    for (n in names (log)) {
+        type <- ifelse (n %in% char_nms, "character", "integer")
+        if (n == "timestamp") {
+            expect_s3_class (log [[n]], "POSIXct")
+        } else {
+            expect_type (log [[n]], type)
+        }
+    }
+
+    fs::dir_delete (path)
+})