diff --git a/go/store/nbs/aws_table_persister.go b/go/store/nbs/aws_table_persister.go
index 242f399bf5..f95aafcf3f 100644
--- a/go/store/nbs/aws_table_persister.go
+++ b/go/store/nbs/aws_table_persister.go
@@ -518,6 +518,7 @@ func (mp manualPart) run(ctx context.Context, buff []byte) error {
 	if err != nil {
 		return err
 	}
+	defer reader.Close()
 	_, err = io.ReadFull(reader, buff[mp.start:mp.end])
 	return err
 }
diff --git a/go/store/nbs/conjoiner.go b/go/store/nbs/conjoiner.go
index bc0085b84c..3c23e77f69 100644
--- a/go/store/nbs/conjoiner.go
+++ b/go/store/nbs/conjoiner.go
@@ -91,7 +91,7 @@ func (c noopConjoiner) chooseConjoinees(sources []tableSpec) (conjoinees, keeper
 // process actor has already landed a conjoin of its own. Callers must
 // handle this, likely by rebasing against upstream and re-evaluating the
 // situation.
-func conjoin(ctx context.Context, s conjoinStrategy, upstream manifestContents, mm manifestUpdater, p tablePersister, stats *Stats) (manifestContents, error) {
+func conjoin(ctx context.Context, s conjoinStrategy, upstream manifestContents, mm manifestUpdater, p tablePersister, stats *Stats) (manifestContents, cleanupFunc, error) {
 	var conjoined tableSpec
 	var conjoinees, keepers, appendixSpecs []tableSpec
 	var cleanup cleanupFunc
@@ -108,12 +108,12 @@ func conjoin(ctx context.Context, s conjoinStrategy, upstream manifestContents,
 			var err error
 			conjoinees, keepers, err = s.chooseConjoinees(upstream.specs)
 			if err != nil {
-				return manifestContents{}, err
+				return manifestContents{}, nil, err
 			}
 
 			conjoined, cleanup, err = conjoinTables(ctx, conjoinees, p, stats)
 			if err != nil {
-				return manifestContents{}, err
+				return manifestContents{}, nil, err
 			}
 		}
 
@@ -137,12 +137,11 @@ func conjoin(ctx context.Context, s conjoinStrategy, upstream manifestContents,
 		var err error
 		upstream, err = mm.Update(ctx, upstream.lock, newContents, stats, nil)
 		if err != nil {
-			return manifestContents{}, err
+			return manifestContents{}, nil, err
 		}
 
 		if newContents.lock == upstream.lock {
-			cleanup()
-			return upstream, nil
+			return upstream, cleanup, nil
 		}
 
 		// Optimistic lock failure. Someone else moved to the root, the
@@ -158,11 +157,11 @@ func conjoin(ctx context.Context, s conjoinStrategy, upstream manifestContents,
 		// and let the client retry
 		if len(appendixSpecs) > 0 {
 			if len(upstream.appendix) != len(appendixSpecs) {
-				return upstream, nil
+				return upstream, func() {}, nil
 			}
 			for i := range upstream.appendix {
 				if upstream.appendix[i].name != appendixSpecs[i].name {
-					return upstream, nil
+					return upstream, func() {}, nil
 				}
 			}
 
@@ -179,7 +178,7 @@ func conjoin(ctx context.Context, s conjoinStrategy, upstream manifestContents,
 		}
 		for _, c := range conjoinees {
 			if _, present := upstreamNames[c.name]; !present {
-				return upstream, nil // Bail!
+				return upstream, func() {}, nil // Bail!
 			}
 			conjoineeSet[c.name] = struct{}{}
 		}
diff --git a/go/store/nbs/conjoiner_test.go b/go/store/nbs/conjoiner_test.go
index 19cd246e21..fe0bdf4d4c 100644
--- a/go/store/nbs/conjoiner_test.go
+++ b/go/store/nbs/conjoiner_test.go
@@ -206,7 +206,7 @@ func testConjoin(t *testing.T, factory func(t *testing.T) tablePersister) {
 			t.Run(c.name, func(t *testing.T) {
 				fm, p, upstream := setup(startLock, startRoot, c.precompact)
 
-				_, err := conjoin(context.Background(), inlineConjoiner{}, upstream, fm, p, stats)
+				_, _, err := conjoin(context.Background(), inlineConjoiner{}, upstream, fm, p, stats)
 				require.NoError(t, err)
 				exists, newUpstream, err := fm.ParseIfExists(context.Background(), stats, nil)
 				require.NoError(t, err)
@@ -227,7 +227,7 @@ func testConjoin(t *testing.T, factory func(t *testing.T) tablePersister) {
 					specs := append([]tableSpec{}, upstream.specs...)
 					fm.set(constants.NomsVersion, computeAddr([]byte("lock2")), startRoot, append(specs, newTable), nil)
 				}}
-				_, err := conjoin(context.Background(), inlineConjoiner{}, upstream, u, p, stats)
+				_, _, err := conjoin(context.Background(), inlineConjoiner{}, upstream, u, p, stats)
 				require.NoError(t, err)
 				exists, newUpstream, err := fm.ParseIfExists(context.Background(), stats, nil)
 				require.NoError(t, err)
@@ -247,7 +247,7 @@ func testConjoin(t *testing.T, factory func(t *testing.T) tablePersister) {
 				u := updatePreemptManifest{fm, func() {
 					fm.set(constants.NomsVersion, computeAddr([]byte("lock2")), startRoot, upstream.specs[1:], nil)
 				}}
-				_, err := conjoin(context.Background(), inlineConjoiner{}, upstream, u, p, stats)
+				_, _, err := conjoin(context.Background(), inlineConjoiner{}, upstream, u, p, stats)
 				require.NoError(t, err)
 				exists, newUpstream, err := fm.ParseIfExists(context.Background(), stats, nil)
 				require.NoError(t, err)
@@ -289,7 +289,7 @@ func testConjoin(t *testing.T, factory func(t *testing.T) tablePersister) {
 			t.Run(c.name, func(t *testing.T) {
 				fm, p, upstream := setupAppendix(startLock, startRoot, c.precompact, c.appendix)
 
-				_, err := conjoin(context.Background(), inlineConjoiner{}, upstream, fm, p, stats)
+				_, _, err := conjoin(context.Background(), inlineConjoiner{}, upstream, fm, p, stats)
 				require.NoError(t, err)
 				exists, newUpstream, err := fm.ParseIfExists(context.Background(), stats, nil)
 				require.NoError(t, err)
@@ -313,7 +313,7 @@ func testConjoin(t *testing.T, factory func(t *testing.T) tablePersister) {
 					fm.set(constants.NomsVersion, computeAddr([]byte("lock2")), startRoot, append(specs, newTable), upstream.appendix)
 				}}
 
-				_, err := conjoin(context.Background(), inlineConjoiner{}, upstream, u, p, stats)
+				_, _, err := conjoin(context.Background(), inlineConjoiner{}, upstream, u, p, stats)
 				require.NoError(t, err)
 				exists, newUpstream, err := fm.ParseIfExists(context.Background(), stats, nil)
 				require.NoError(t, err)
@@ -338,7 +338,7 @@ func testConjoin(t *testing.T, factory func(t *testing.T) tablePersister) {
 					fm.set(constants.NomsVersion, computeAddr([]byte("lock2")), startRoot, append(specs, upstream.specs...), append(app, newTable))
 				}}
 
-				_, err := conjoin(context.Background(), inlineConjoiner{}, upstream, u, p, stats)
+				_, _, err := conjoin(context.Background(), inlineConjoiner{}, upstream, u, p, stats)
 				require.NoError(t, err)
 				exists, newUpstream, err := fm.ParseIfExists(context.Background(), stats, nil)
 				require.NoError(t, err)
@@ -362,7 +362,7 @@ func testConjoin(t *testing.T, factory func(t *testing.T) tablePersister) {
 				u := updatePreemptManifest{fm, func() {
 					fm.set(constants.NomsVersion, computeAddr([]byte("lock2")), startRoot, upstream.specs[len(c.appendix)+1:], upstream.appendix[:])
 				}}
-				_, err := conjoin(context.Background(), inlineConjoiner{}, upstream, u, p, stats)
+				_, _, err := conjoin(context.Background(), inlineConjoiner{}, upstream, u, p, stats)
 				require.NoError(t, err)
 				exists, newUpstream, err := fm.ParseIfExists(context.Background(), stats, nil)
 				require.NoError(t, err)
@@ -386,7 +386,7 @@ func testConjoin(t *testing.T, factory func(t *testing.T) tablePersister) {
 					fm.set(constants.NomsVersion, computeAddr([]byte("lock2")), startRoot, specs, append([]tableSpec{}, newTable))
 				}}
 
-				_, err := conjoin(context.Background(), inlineConjoiner{}, upstream, u, p, stats)
+				_, _, err := conjoin(context.Background(), inlineConjoiner{}, upstream, u, p, stats)
 				require.NoError(t, err)
 				exists, newUpstream, err := fm.ParseIfExists(context.Background(), stats, nil)
 				require.NoError(t, err)
diff --git a/go/store/nbs/file_table_persister.go b/go/store/nbs/file_table_persister.go
index b3a339591b..a3670111f7 100644
--- a/go/store/nbs/file_table_persister.go
+++ b/go/store/nbs/file_table_persister.go
@@ -168,7 +168,7 @@ func (ftp *fsTablePersister) ConjoinAll(ctx context.Context, sources chunkSource
 	}
 
 	if plan.chunkCount == 0 {
-		return emptyChunkSource{}, nil, nil
+		return emptyChunkSource{}, func() {}, nil
 	}
 
 	name := nameFromSuffixes(plan.suffixes())
@@ -189,22 +189,27 @@ func (ftp *fsTablePersister) ConjoinAll(ctx context.Context, sources chunkSource
 		}()
 
 		for _, sws := range plan.sources.sws {
-			var r io.Reader
+			var r io.ReadCloser
 			r, _, ferr = sws.source.reader(ctx)
-
 			if ferr != nil {
 				return "", ferr
 			}
 
 			n, ferr := io.CopyN(temp, r, int64(sws.dataLen))
-
 			if ferr != nil {
+				r.Close()
 				return "", ferr
 			}
 
 			if uint64(n) != sws.dataLen {
+				r.Close()
 				return "", errors.New("failed to copy all data")
 			}
+
+			err := r.Close()
+			if err != nil {
+				return "", err
+			}
 		}
 
 		_, ferr = temp.Write(plan.mergedIndex)
diff --git a/go/store/nbs/store.go b/go/store/nbs/store.go
index 8dc240ebb2..b4777c92b3 100644
--- a/go/store/nbs/store.go
+++ b/go/store/nbs/store.go
@@ -1120,7 +1120,7 @@ func (nbs *NomsBlockStore) updateManifest(ctx context.Context, current, last has
 	}
 
 	if nbs.c.conjoinRequired(nbs.tables) {
-		newUpstream, err := conjoin(ctx, nbs.c, nbs.upstream, nbs.mm, nbs.p, nbs.stats)
+		newUpstream, cleanup, err := conjoin(ctx, nbs.c, nbs.upstream, nbs.mm, nbs.p, nbs.stats)
 		if err != nil {
 			return err
 		}
@@ -1137,6 +1137,7 @@ func (nbs *NomsBlockStore) updateManifest(ctx context.Context, current, last has
 		if err != nil {
 			return err
 		}
+		cleanup()
 		return errOptimisticLockFailedTables
 	}