diff --git a/hledger-lib/Hledger/Data/Journal.hs b/hledger-lib/Hledger/Data/Journal.hs
index 710be6859..913f17022 100644
--- a/hledger-lib/Hledger/Data/Journal.hs
+++ b/hledger-lib/Hledger/Data/Journal.hs
@@ -38,9 +38,8 @@ module Hledger.Data.Journal (
   filterTransactionPostings,
   filterPostingAmount,
   -- * Mapping
-  mapJournalTransactions,
-  mapJournalPostings,
-  mapTransactionPostings,
+  journalMapTransactions,
+  journalMapPostings,
   journalMapPostingAmounts,
   -- * Querying
   journalAccountNamesUsed,
@@ -445,20 +444,16 @@ filterTransactionPostings :: Query -> Transaction -> Transaction
 filterTransactionPostings q t@Transaction{tpostings=ps} = t{tpostings=filter (q `matchesPosting`) ps}
 
 -- | Apply a transformation to a journal's transactions.
-mapJournalTransactions :: (Transaction -> Transaction) -> Journal -> Journal
-mapJournalTransactions f j@Journal{jtxns=ts} = j{jtxns=map f ts}
+journalMapTransactions :: (Transaction -> Transaction) -> Journal -> Journal
+journalMapTransactions f j@Journal{jtxns=ts} = j{jtxns=map f ts}
 
 -- | Apply a transformation to a journal's postings.
-mapJournalPostings :: (Posting -> Posting) -> Journal -> Journal
-mapJournalPostings f j@Journal{jtxns=ts} = j{jtxns=map (mapTransactionPostings f) ts}
-
--- | Apply a transformation to a transaction's postings.
-mapTransactionPostings :: (Posting -> Posting) -> Transaction -> Transaction
-mapTransactionPostings f t@Transaction{tpostings=ps} = t{tpostings=map f ps}
+journalMapPostings :: (Posting -> Posting) -> Journal -> Journal
+journalMapPostings f j@Journal{jtxns=ts} = j{jtxns=map (transactionMapPostings f) ts}
 
 -- | Apply a transformation to a journal's posting amounts.
 journalMapPostingAmounts :: (Amount -> Amount) -> Journal -> Journal
-journalMapPostingAmounts f = mapJournalPostings (postingTransformAmount (mapMixedAmount f))
+journalMapPostingAmounts f = journalMapPostings (postingTransformAmount (mapMixedAmount f))
 
 {-
 -------------------------------------------------------------------------------
diff --git a/hledger-lib/Hledger/Data/Transaction.hs b/hledger-lib/Hledger/Data/Transaction.hs
index 40927ccdc..5ffa9c44e 100644
--- a/hledger-lib/Hledger/Data/Transaction.hs
+++ b/hledger-lib/Hledger/Data/Transaction.hs
@@ -36,6 +36,7 @@ module Hledger.Data.Transaction (
   transactionApplyValuation,
   transactionToCost,
   transactionApplyAliases,
+  transactionMapPostings,
   -- nonzerobalanceerror,
   -- * date operations
   transactionDate2,
@@ -617,6 +618,11 @@ transactionApplyAliases aliases t =
     Right ps -> Right $ txnTieKnot $ t{tpostings=ps}
     Left err -> Left err
 
+-- | Apply a transformation to a transaction's postings.
+transactionMapPostings :: (Posting -> Posting) -> Transaction -> Transaction
+transactionMapPostings f t@Transaction{tpostings=ps} = t{tpostings=map f ps}
+
+-- | Apply a transformation to a transaction's posting amounts.
 -- tests
 
 tests_Transaction :: TestTree