diff --git a/sforth/forth.hpp b/sforth/forth.hpp
index 9e0a59e..52d0585 100644
--- a/sforth/forth.hpp
+++ b/sforth/forth.hpp
@@ -208,6 +208,7 @@ constexpr auto initialize()
         , S{"dp"   }, [](auto) { fthp->push(std::bit_cast<cell>(fthp) + 4 * sizeof(cell)); }, 0
         , S{"state"}, [](auto) { fthp->push(std::bit_cast<cell>(fthp) + 7 * sizeof(cell)); }, 0
         , S{"base" }, [](auto) { fthp->push(std::bit_cast<cell>(fthp) + 8 * sizeof(cell)); }, 0
+        , S{"depth"}, [](auto) { fthp->push(std::distance(fthp->sp, fthp->dstack.end())); }, 0
         , S{"unused"}, [](auto) { fthp->push(sizeof(cell) * std::distance(fthp->here, fthp->dict.end())); }, 0
         , S{"_lit" }, lit_impl, 0
         , S{"swap" }, [](auto) { auto a = fthp->pop(); auto b = fthp->pop(); fthp->push(a, b); }, 0
@@ -264,6 +265,13 @@ constexpr auto initialize()
             auto g = fthp->get(w);
             assert<error::word_not_found>(g.has_value());
             *fthp->here++ = std::bit_cast<cell>((*g)->body()); }, word_base::immediate
+        , S{"source"}, [](auto) {
+            auto len = 0u;
+            while (fthp->source[len])
+                len++;
+            fthp->push(std::bit_cast<cell>(fthp->source));
+            fthp->push(len); }, 0
+        , S{">in"}, [](auto) { fthp->push(std::bit_cast<cell>(&fthp->sourcei)); }, 0
     >::word;
     constexpr static auto& dict2 = comp_dict<prologue, &dict1
         , S{"align"  }, S{"here dup aligned swap - allot"}, 0
@@ -303,6 +311,8 @@ constexpr auto initialize()
         , S{"negate"}, S{"-1 *"}, 0
         , S{"2*"    }, S{"2 *"}, 0
         , S{"bl"    }, S{"32"}, 0
+        , S{"false" }, S{"0"}, 0
+        , S{"true"  }, S{"-1"}, 0
     >::word;
 
     return &dict2;