diff --git a/cabal.project b/cabal.project
index c216d6e9ce25190cc1b5794854ce6eae5b300174..1873927ee2d18ce296e8173440e4e3979f48234e 100644
--- a/cabal.project
+++ b/cabal.project
@@ -3,7 +3,7 @@ packages: .
           -- straight from the vcs host.  Probably should do some releases
           -- soon.
           https://whetstone.private.storage/privatestorage/tahoe-chk/-/archive/0.1.0.0/tahoe-chk-0.1.0.0.tar.gz
-          https://whetstone.private.storage/privatestorage/tahoe-great-black-swamp/-/archive/0.1.0.1/tahoe-great-black-swamp-0.1.0.1.tar.gz
+          https://whetstone.private.storage/privatestorage/tahoe-great-black-swamp/-/archive/0.2.0.1/tahoe-great-black-swamp-0.2.0.1.tar.gz
 
 package zlib
         -- Turn on discovery of the underlying zlib using pkg-config.  This
diff --git a/gbs-downloader.cabal b/gbs-downloader.cabal
index a12f83034b52495858f7d2b2a41d17c39358c657..71d08e5765f5189c09c65c5dbe767441e86a9586 100644
--- a/gbs-downloader.cabal
+++ b/gbs-downloader.cabal
@@ -102,7 +102,7 @@ library
     , servant-client
     , servant-client-core
     , tahoe-chk
-    , tahoe-great-black-swamp
+    , tahoe-great-black-swamp  >=0.2       && <0.3
     , text
     , yaml