diff --git a/cabal.project b/cabal.project
index 3db828a76..11f083f5d 100644
--- a/cabal.project
+++ b/cabal.project
@@ -5,4 +5,4 @@ optimization: False
 source-repository-package
   type: git
   location: https://github.com/fossas/yarn-lock.git
-  tag: master
+  tag: 1ac8875f73eaf76237d506e900f944a34ad3c0fb
diff --git a/cabal.project.ci.linux b/cabal.project.ci.linux
index ff4a164b3..6962b925d 100644
--- a/cabal.project.ci.linux
+++ b/cabal.project.ci.linux
@@ -11,4 +11,4 @@ package spectrometer
 source-repository-package
   type: git
   location: https://github.com/fossas/yarn-lock.git
-  tag: master
+  tag: 1ac8875f73eaf76237d506e900f944a34ad3c0fb
diff --git a/cabal.project.ci.macos b/cabal.project.ci.macos
index 574f96a56..2ab2bd4f7 100644
--- a/cabal.project.ci.macos
+++ b/cabal.project.ci.macos
@@ -9,4 +9,4 @@ package spectrometer
 source-repository-package
   type: git
   location: https://github.com/fossas/yarn-lock.git
-  tag: master
+  tag: 1ac8875f73eaf76237d506e900f944a34ad3c0fb
diff --git a/cabal.project.ci.windows b/cabal.project.ci.windows
index ff4a164b3..6962b925d 100644
--- a/cabal.project.ci.windows
+++ b/cabal.project.ci.windows
@@ -11,4 +11,4 @@ package spectrometer
 source-repository-package
   type: git
   location: https://github.com/fossas/yarn-lock.git
-  tag: master
+  tag: 1ac8875f73eaf76237d506e900f944a34ad3c0fb