diff --git a/dev-dotnet/coco/Manifest b/dev-dotnet/coco/Manifest
index fc5826d0ef1c5..acf5b3ef3e335 100644
--- a/dev-dotnet/coco/Manifest
+++ b/dev-dotnet/coco/Manifest
@@ -1 +1,2 @@
 DIST coco-2014.12.24.tar.gz 37670 BLAKE2B acd2299e3452d4dac495a0a7f897694791b4abcc0dd7c243771fe8c7084cd9909110c655788844e11fbb576bd95e3596cb890c0ec930c3e4587fd3313082b5cb SHA512 d3b5af1b73b233a8c4b4572db8d65b1c1ffec36e455e4d5fadf1002125433551c833b9574ae03edbe2cd3978fedef41c85667fce82ff2d6ee155c16f778f970e
+DIST coco-2014.12.25.snapshot.gh.tar.gz 37724 BLAKE2B ba399980bfdc7772371f83c1913e2a9188b9d85c4db5c079dc6897b4503f994416b0da829c7dffc2fb295688b1607e468b281fd02c32a824ad878825daea859f SHA512 e8e1985f0d044a9b985c04e82e512a35692a7bb83d3691f806727ddc791908e25f2f4a8da52f0213e9c437ffc14cae89b2bb0e86769e1f4d0d73a83973fbe8d4
diff --git a/dev-dotnet/coco/coco-2014.12.25.ebuild b/dev-dotnet/coco/coco-2014.12.25.ebuild
new file mode 100644
index 0000000000000..1098888311826
--- /dev/null
+++ b/dev-dotnet/coco/coco-2014.12.25.ebuild
@@ -0,0 +1,46 @@
+# Copyright 1999-2025 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+# Upstream did not tag this release.
+if [[ "${PV}" == "2014.12.25" ]] ; then
+	COMMIT_SHA="14be0314ae393569ab7abaf4e187f78e6d42b2fd"
+else
+	die 'Could not detect "COMMIT_SHA", please update the ebuild.'
+fi
+
+DOTNET_PKG_COMPAT="9.0"
+NUGET_PACKAGES=""
+
+inherit dotnet-pkg
+
+DESCRIPTION="The compiler generator Coco/R for C#"
+HOMEPAGE="https://github.com/boogie-org/coco/"
+
+if [[ "${PV}" == *9999* ]] ; then
+	inherit git-r3
+
+	EGIT_REPO_URI="https://github.com/boogie-org/${PN}.git"
+else
+	SRC_URI="https://github.com/boogie-org/${PN}/archive/${COMMIT_SHA}.tar.gz
+		-> ${P}.snapshot.gh.tar.gz"
+	S="${WORKDIR}/${PN}-${COMMIT_SHA}"
+
+	KEYWORDS="~amd64"
+fi
+
+LICENSE="GPL-2+"
+SLOT="0"
+
+DOTNET_PKG_PROJECTS=( Coco.csproj )
+
+dotnet-pkg_force-compat
+
+src_unpack() {
+	dotnet-pkg_src_unpack
+
+	if [[ -n "${EGIT_REPO_URI}" ]] ; then
+		git-r3_src_unpack
+	fi
+}