diff --git a/Clarinet.toml b/Clarinet.toml
index 5a70b35..3f17206 100644
--- a/Clarinet.toml
+++ b/Clarinet.toml
@@ -40,6 +40,11 @@ path = 'contracts/helper.clar'
 clarity_version = 2
 epoch = 2.1
 
+[contracts.clarity-bitcoin-helper_test]
+path = 'contracts/tests/clarity-bitcoin-helper_test.clar'
+clarity_version = 2
+epoch = 2.1
+
 [contracts.send-to-first-input]
 path = 'contracts/examples/send-to-first-input.clar'
 clarity_version = 2
diff --git a/contracts/tests/clarity-bitcoin-helper_test.clar b/contracts/tests/clarity-bitcoin-helper_test.clar
new file mode 100644
index 0000000..db4d83d
--- /dev/null
+++ b/contracts/tests/clarity-bitcoin-helper_test.clar
@@ -0,0 +1,17 @@
+;; @name concat tx with empty data
+(define-public (test-concat-tx-empty)
+  (let ((result (contract-call? .clarity-bitcoin-helper concat-tx
+                               {ins: (list), outs: (list), version: 0x, locktime: 0x})))
+    (asserts! (is-eq result 0x0000) (err result))
+    (ok true)))
+
+;; @name concat tx with most data possible per in and out
+(define-public (test-concat-tx-max-1)
+  (let ((result (contract-call? .clarity-bitcoin-helper concat-tx
+                               {ins: (list {outpoint: {hash: 0x112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00, index: 0x00112233}, scriptSig: 0x112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00, sequence: 0x11223344}
+                               ),
+                               outs: (list {value: 0x0011223344556677, scriptPubKey: 0x112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00}),
+                               version: 0x11223344, locktime: 0x44332211})))
+    (asserts! (is-eq result 0x1122334401112233445566778899aabbccddeeff00112233445566778899aabbccddeeff000011223380112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff001122334401001122334455667780112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff0044332211) (err result))
+    (ok true)))
+