diff --git a/core/btyacc/build b/core/btyacc/build
new file mode 100755
index 00000000..425c9f7d
--- /dev/null
+++ b/core/btyacc/build
@@ -0,0 +1,6 @@
+#!/bin/sh -e
+
+make
+
+mkdir -p "$1/usr/bin"
+cp -f btyacc "$1/usr/bin/yacc"
diff --git a/core/btyacc/checksums b/core/btyacc/checksums
new file mode 100644
index 00000000..e292eae7
--- /dev/null
+++ b/core/btyacc/checksums
@@ -0,0 +1 @@
+33de88872e790cf4f64d336b55f80ca2d2f9fa500de4440d0a8f5e7bddccbfdb85
diff --git a/core/btyacc/sources b/core/btyacc/sources
new file mode 100644
index 00000000..bb7c1e83
--- /dev/null
+++ b/core/btyacc/sources
@@ -0,0 +1 @@
+https://www.siber.com/btyacc/btyacc-3-0.tar.gz
diff --git a/core/btyacc/version b/core/btyacc/version
new file mode 100644
index 00000000..fe8659a5
--- /dev/null
+++ b/core/btyacc/version
@@ -0,0 +1 @@
+3-0 1