diff --git a/substrate/tendermint/machine/src/block.rs b/substrate/tendermint/machine/src/block.rs
new file mode 100644
index 00000000..9c100ccc
--- /dev/null
+++ b/substrate/tendermint/machine/src/block.rs
@@ -0,0 +1,23 @@
+use std::collections::{HashSet, HashMap};
+
+use crate::{
+  time::CanonicalInstant,
+  ext::{RoundNumber, BlockNumber, Block, Network},
+  round::RoundData,
+  message_log::MessageLog,
+};
+
+pub(crate) struct BlockData<N: Network> {
+  pub(crate) number: BlockNumber,
+  pub(crate) validator_id: Option<N::ValidatorId>,
+  pub(crate) proposal: N::Block,
+
+  pub(crate) log: MessageLog<N>,
+  pub(crate) slashes: HashSet<N::ValidatorId>,
+  pub(crate) end_time: HashMap<RoundNumber, CanonicalInstant>,
+
+  pub(crate) round: RoundData<N>,
+
+  pub(crate) locked: Option<(RoundNumber, <N::Block as Block>::Id)>,
+  pub(crate) valid: Option<(RoundNumber, N::Block)>,
+}
diff --git a/substrate/tendermint/machine/src/lib.rs b/substrate/tendermint/machine/src/lib.rs
index 0a28c0ee..ab996724 100644
--- a/substrate/tendermint/machine/src/lib.rs
+++ b/substrate/tendermint/machine/src/lib.rs
@@ -16,10 +16,13 @@ use futures::{
 use tokio::time::sleep;
 
 mod time;
-use time::*;
+use time::{sys_time, CanonicalInstant};
 
 mod round;
-use round::*;
+use round::RoundData;
+
+mod block;
+use block::BlockData;
 
 mod message_log;
 use message_log::MessageLog;
@@ -106,21 +109,6 @@ enum TendermintError<V: ValidatorId> {
   Temporal,
 }
 
-struct BlockData<N: Network> {
-  number: BlockNumber,
-  validator_id: Option<N::ValidatorId>,
-  proposal: N::Block,
-
-  log: MessageLog<N>,
-  slashes: HashSet<N::ValidatorId>,
-  end_time: HashMap<RoundNumber, CanonicalInstant>,
-
-  round: RoundData<N>,
-
-  locked: Option<(RoundNumber, <N::Block as Block>::Id)>,
-  valid: Option<(RoundNumber, N::Block)>,
-}
-
 /// A machine executing the Tendermint protocol.
 pub struct TendermintMachine<N: Network> {
   network: N,