diff --git a/commit_verify/src/bin/commit-stl.rs b/commit_verify/src/bin/commit-stl.rs
index fec4d32f..a13f01a5 100644
--- a/commit_verify/src/bin/commit-stl.rs
+++ b/commit_verify/src/bin/commit-stl.rs
@@ -12,15 +12,20 @@
 // You should have received a copy of the Apache 2.0 License along with this
 // software. If not, see <https://opensource.org/licenses/Apache-2.0>.
 
-use commit_verify::stl;
-use strict_types::parse_args;
+use std::fs;
+use std::io::Write;
+
+use commit_verify::stl::commit_verify_stl;
+use commit_verify::{mpc, CommitmentLayout, MerkleNode};
+use strict_types::stl::{std_stl, strict_types_stl};
+use strict_types::{parse_args, SystemBuilder};
 
 fn main() {
-    let lib = stl::commit_verify_stl();
+    let lib = commit_verify_stl();
     let (format, dir) = parse_args();
     lib.serialize(
         format,
-        dir,
+        dir.as_ref(),
         "0.1.0",
         Some(
             "
@@ -31,4 +36,56 @@ fn main() {
         ),
     )
     .expect("unable to write to the file");
+
+    let dir = dir.unwrap_or_else(|| ".".to_owned());
+
+    let std = std_stl();
+    let st = strict_types_stl();
+    let cv = commit_verify_stl();
+
+    let sys = SystemBuilder::new()
+        .import(cv)
+        .unwrap()
+        .import(st)
+        .unwrap()
+        .import(std)
+        .unwrap()
+        .finalize()
+        .expect("not all libraries present");
+
+    let mut file = fs::File::create(format!("{dir}/Merkle.vesper")).unwrap();
+    writeln!(
+        file,
+        "{{-
+  Description: Merklization and MPC workflows
+  Author: Dr Maxim Orlovsky <orlovsky@lnp-bp.org>
+  Copyright (C) 2024 LNP/BP Standards Association. All rights reserved.
+  License: Apache-2.0
+-}}
+
+Merklization vesper lexicon=types+commitments
+"
+    )
+    .unwrap();
+    writeln!(file, "\n-- General merklization workflows\n").unwrap();
+    let layout = MerkleNode::commitment_layout();
+    writeln!(file, "{layout}").unwrap();
+    let tt = sys.type_tree("CommitVerify.MerkleNode").unwrap();
+    writeln!(file, "{tt}").unwrap();
+
+    writeln!(file, "\n-- Multi-protocol commitment workflows\n").unwrap();
+    let layout = mpc::Leaf::commitment_layout();
+    writeln!(file, "{layout}").unwrap();
+    let tt = sys.type_tree("CommitVerify.Leaf").unwrap();
+    writeln!(file, "{tt}").unwrap();
+
+    let layout = mpc::MerkleBlock::commitment_layout();
+    writeln!(file, "{layout}").unwrap();
+    let tt = sys.type_tree("CommitVerify.MerkleBlock").unwrap();
+    writeln!(file, "{tt}").unwrap();
+
+    let layout = mpc::MerkleTree::commitment_layout();
+    writeln!(file, "{layout}").unwrap();
+    let tt = sys.type_tree("CommitVerify.MerkleTree").unwrap();
+    writeln!(file, "{tt}").unwrap();
 }
diff --git a/stl/Merkle.vesper b/stl/Merkle.vesper
new file mode 100644
index 00000000..dac8c267
--- /dev/null
+++ b/stl/Merkle.vesper
@@ -0,0 +1,83 @@
+{-
+  Description: Merklization and MPC workflows
+  Author: Dr Maxim Orlovsky <orlovsky@lnp-bp.org>
+  Copyright (C) 2024 LNP/BP Standards Association. All rights reserved.
+  License: Apache-2.0
+-}
+
+Merklization vesper lexicon=types+commitments
+
+
+-- General merklization workflows
+
+MerkleHash commitment hasher=SHA256 tagged=urn:ubideco:merkle:node#2024-01-31
+  MerkleNode serialized
+
+MerkleNode rec
+  branching enum void=0 single=1 branch=2 -- NodeBranching
+  depth is U8
+  width is U256
+  node1 bytes len=32 aka=MerkleHash
+  node2 bytes len=32 aka=MerkleHash
+
+
+-- Multi-protocol commitment workflows
+
+MerkleHash commitment hasher=SHA256 tagged=urn:ubideco:merkle:node#2024-01-31
+  Leaf serialized
+
+Leaf union
+  inhabited rec tag=0
+    protocol bytes len=32 aka=ProtocolId
+    message bytes len=32 aka=Message
+  entropy rec tag=1
+    entropy is U64
+    pos is U32
+
+Commitment commitment hasher=SHA256 tagged=urn:ubideco:mpc:commitment#2024-01-31
+  MerkleBlock concealed concealed=MerkleBlock
+
+MerkleBlock rec
+  depth enum {
+    _0=0 _1=1 _2=2 _3=3 _4=4 _5=5 _6=6 _7=7 _8=8
+    _9=9 _10=10 _11=11 _12=12 _13=13 _14=14 _15=15 _16=16
+    _17=17 _18=18 _19=19 _20=20 _21=21 _22=22 _23=23 _24=24
+    _25=25 _26=26 _27=27 _28=28 _29=29 _30=30 _31=31
+  } -- U5
+  cofactor is U16
+  crossSection list len=1..MAX32
+    TreeNode union
+      concealedNode rec tag=0
+        depth enum {
+          _0=0 _1=1 _2=2 _3=3 _4=4 _5=5 _6=6 _7=7 _8=8
+          _9=9 _10=10 _11=11 _12=12 _13=13 _14=14 _15=15 _16=16
+          _17=17 _18=18 _19=19 _20=20 _21=21 _22=22 _23=23 _24=24
+          _25=25 _26=26 _27=27 _28=28 _29=29 _30=30 _31=31
+        } -- U5
+        hash bytes len=32 aka=MerkleHash
+      commitmentLeaf rec tag=1
+        protocolId bytes len=32 aka=ProtocolId
+        message bytes len=32 aka=Message
+    some is U64 option wrapped tag=1
+
+Commitment commitment hasher=SHA256 tagged=urn:ubideco:mpc:commitment#2024-01-31
+  MerkleBlock concealed concealed=MerkleBlock
+
+MerkleTree rec
+  depth enum {
+    _0=0 _1=1 _2=2 _3=3 _4=4 _5=5 _6=6 _7=7 _8=8
+    _9=9 _10=10 _11=11 _12=12 _13=13 _14=14 _15=15 _16=16
+    _17=17 _18=18 _19=19 _20=20 _21=21 _22=22 _23=23 _24=24
+    _25=25 _26=26 _27=27 _28=28 _29=29 _30=30 _31=31
+  } -- U5
+  entropy is U64
+  cofactor is U16
+  messages map len=0..MAX24
+    key bytes len=32 aka=ProtocolId
+    value bytes len=32 aka=Message
+  map map len=0..MAX24
+    key is U32
+    value tuple
+      _ bytes len=32 aka=ProtocolId
+      _ bytes len=32 aka=Message
+