diff --git a/lama-spec.pdf b/lama-spec.pdf
index 02dc803f7..c9be9504f 100644
Binary files a/lama-spec.pdf and b/lama-spec.pdf differ
diff --git a/runtime/Std.i b/runtime/Std.i
index 65e32159e..b3ff0f94a 100644
--- a/runtime/Std.i
+++ b/runtime/Std.i
@@ -1,3 +1,4 @@
+F,assert;
 F,getEnv;
 F,system;
 V,sysargs;
diff --git a/runtime/runtime.c b/runtime/runtime.c
index 54f6ebbcd..117844e89 100644
--- a/runtime/runtime.c
+++ b/runtime/runtime.c
@@ -151,6 +151,15 @@ static void failure (char *s, ...) {
   vfailure (s, args);
 }
 
+void Lassert (void *f, char *s, ...) {
+  if (!UNBOX(f)) {
+    va_list args;
+
+    va_start (args, s);
+    vfailure (s, args);    
+  }
+}
+
 # define ASSERT_BOXED(memo, x)               \
   do if (UNBOXED(x)) failure ("boxed value expected in %s\n", memo); while (0)
 # define ASSERT_UNBOXED(memo, x)             \
diff --git a/spec/07.standard_library.tex b/spec/07.standard_library.tex
index c514ad417..525d01063 100644
--- a/spec/07.standard_library.tex
+++ b/spec/07.standard_library.tex
@@ -12,6 +12,9 @@ is added implicitly by the compiler and can not be specified by an end user.
 
 The following declarations are accessible:
 
+\descr{\lstinline|fun assert (n, s, ...)|}{Asserts that \lstinline|n| is non-zero; otherwise raises \lstinline|failure| with
+  a corresponding error message.}
+
 \descr{\lstinline|fun stringInt (s)|}{Converts a string representation of a signed decimal number into integer.}
 
 \descr{\lstinline|fun read ()|}{Reads an integer value from the standard input, printing a prompt "\lstinline|>|".}
diff --git a/src/stdpath.ml b/src/stdpath.ml
index c85a32af0..3ea09b8ff 100644
--- a/src/stdpath.ml
+++ b/src/stdpath.ml
@@ -1 +1 @@
-let path = "/home/db/.opam/4.07.1+fp/share/Lama"
+let path = "/home/db/.opam/4.07.1+fp+flambda/share/Lama"
diff --git a/src/version.ml b/src/version.ml
index 7c82e5147..cfc8d681e 100644
--- a/src/version.ml
+++ b/src/version.ml
@@ -1 +1 @@
-let version = "Version 1.00, 19252991a, Thu Dec 24 02:54:54 2020 +0300"
+let version = "Version 1.00, eeddb0b25, Tue Jan 12 01:14:18 2021 +0300"