diff --git a/SLS_Python/sls_py.pyi b/SLS_Python/sls_py.pyi
new file mode 100644
index 0000000..b9af9fe
--- /dev/null
+++ b/SLS_Python/sls_py.pyi
@@ -0,0 +1,140 @@
+from dataclasses import dataclass, field
+from enum import Enum, auto
+from typing import Callable, Dict, List, Optional
+
+def main() -> int:
+    ...
+
+SLS_NAME: str
+SLS_VERSION: str
+SLS_COMMIT: str
+INTERPRETER_NAME: str
+INTERPRETER_VER: int
+MODULE_TIMESTAMP: str
+
+
+class LexerInfo:
+    filename: str
+    source_code: str
+    pos: int
+    column: int
+    line: int
+
+    def __init__(self, filename: str = "", source_code: str = ""): ...
+
+
+class TokenType(Enum):
+    EOF = auto()
+    IDENTIFIER = auto()
+    INTEGER = auto()
+    FLOAT = auto()
+    DOUBLE = auto()
+    CHARACTER = auto()
+    STRING = auto()
+    BOOLEAN = auto()
+    ARRAY = auto()
+    TOKEN_STRING = auto()
+    TYPE_TUPLE = auto()
+
+
+@dataclass
+class Identifier:
+    name: str
+    is_literal: bool
+
+
+class IntegerBuiltInType(Enum):
+    I64 = auto()
+    I32 = auto()
+    I16 = auto()
+    I8 = auto()
+    U64 = auto()
+    U32 = auto()
+    U16 = auto()
+    U8 = auto()
+
+
+@dataclass
+class IntegerLiteral:
+    value: int
+    type: IntegerBuiltInType
+
+
+@dataclass
+class TokenString:
+    tokens: List["Token"] = field(default_factory=list)
+
+    def deep_copy(self) -> TokenString: ...
+
+
+@dataclass
+class Token:
+    type: TokenType
+    identifier: Optional[Identifier] = None
+    integer_literal: Optional[IntegerLiteral] = None
+    float_literal: Optional[float] = None
+    double_literal: Optional[float] = None
+    character_literal: Optional[int] = None
+    string_literal: Optional[str] = None
+    boolean_literal: Optional[bool] = None
+    token_string: Optional[TokenString] = None
+
+
+def lexical_analysis(lexer_info: LexerInfo) -> List[Token]:
+    ...
+
+
+class StackType(Enum):
+    IDENTIFIER = auto()
+    I64 = auto()
+    I32 = auto()
+    I16 = auto()
+    I8 = auto()
+    U64 = auto()
+    U32 = auto()
+    U16 = auto()
+    U8 = auto()
+    FLOAT = auto()
+    DOUBLE = auto()
+    CHARACTER = auto()
+    BOOLEAN = auto()
+    TOKEN_STRING = auto()
+    CALLABLE = auto()
+
+@dataclass
+class StackEntry:
+    type: StackType
+    value: object
+
+
+class FunctionType(Enum):
+    TOKEN_STRING = auto()
+    BUILTIN = auto()
+
+
+@dataclass
+class FunctionItem:
+    type: FunctionType
+    token_string: Optional[TokenString] = None
+    builtin: Optional[Callable[["InterpreterState"], bool]] = None
+
+    @classmethod
+    def from_token_string(cls, ts: TokenString) -> "FunctionItem": ...
+    @classmethod
+    def from_builtin(cls, fn: Callable[["InterpreterState"], bool]) -> "FunctionItem": ...
+
+
+class InterpreterState:
+    stack: List[StackEntry]
+    functions: Dict[str, FunctionItem]
+
+    def __init__(self): ...
+    def push(self, entry: StackEntry) -> None: ...
+    def pop(self) -> Optional[StackEntry]: ...
+    def top(self) -> Optional[StackEntry]: ...
+    def add_function(self, name: str, item: FunctionItem) -> None: ...
+    def get_function(self, name: str) -> Optional[FunctionItem]: ...
+    def push_token(self, token: Token) -> bool: ...
+    def execute_func(self, key: str) -> bool: ...
+    def execute_token_string(self, token_string: TokenString) -> bool: ...
+    def execute(self, token: Token) -> bool: ...
diff --git a/SLS_Python/sls_py/__init__.py b/SLS_Python/sls_py/__init__.py
index a9a2aad..3afd27f 100644
--- a/SLS_Python/sls_py/__init__.py
+++ b/SLS_Python/sls_py/__init__.py
@@ -1,6 +1,52 @@
-"""sls — Python SLS reimplementation
+from .__main__ import main
 
-Expose package version and small helpers here.
-"""
+from .meta import (
+    SLS_NAME,
+    SLS_VERSION,
+    SLS_COMMIT,
+    INTERPRETER_NAME,
+    INTERPRETER_VER,
+    MODULE_TIMESTAMP,
+)
 
-__all__ = ["main"]
+from .lexer import (
+    LexerInfo,
+    TokenType,
+    Identifier,
+    IntegerBuiltInType,
+    IntegerLiteral,
+    TokenString,
+    Token,
+    lexical_analysis,
+)
+
+from .interpreter import (
+    StackType,
+    StackEntry,
+    FunctionType,
+    FunctionItem,
+    InterpreterState,
+)
+
+__all__ = [
+    "main",
+    "SLS_NAME",
+    "SLS_VERSION",
+    "SLS_COMMIT",
+    "INTERPRETER_NAME",
+    "INTERPRETER_VER",
+    "MODULE_TIMESTAMP",
+    "LexerInfo",
+    "TokenType",
+    "Identifier",
+    "IntegerBuiltInType",
+    "IntegerLiteral",
+    "TokenString",
+    "Token",
+    "lexical_analysis",
+    "StackType",
+    "StackEntry",
+    "FunctionType",
+    "FunctionItem",
+    "InterpreterState",
+]
diff --git a/SLS_Python/sls_py/meta.py b/SLS_Python/sls_py/meta.py
index 8de7af0..a7304e2 100644
--- a/SLS_Python/sls_py/meta.py
+++ b/SLS_Python/sls_py/meta.py
@@ -8,12 +8,15 @@ except ImportError:
 
 
 SLS_NAME = "SLS_PYTHON"
+SLS_VERSION = version
+SLS_COMMIT = commit
 
 # Runtime interpreter info (Python equivalent of compiler)
 _impl = sys.implementation
 INTERPRETER_NAME = _impl.name.capitalize()
 INTERPRETER_VER = _impl.version.major
+MODULE_TIMESTAMP = timestamp
 
 def print_version() -> None:
-    print(f"YREA SLS ({SLS_NAME}) {version} ({commit})")
-    print(f"Running on {INTERPRETER_NAME} {INTERPRETER_VER} at {timestamp}")
+    print(f"YREA SLS ({SLS_NAME}) {SLS_VERSION} ({SLS_COMMIT})")
+    print(f"Running on {INTERPRETER_NAME} {INTERPRETER_VER} at {MODULE_TIMESTAMP}")
diff --git a/SLS_Python/sls_py/repl.py b/SLS_Python/sls_py/repl.py
index e16c7e8..402be3b 100644
--- a/SLS_Python/sls_py/repl.py
+++ b/SLS_Python/sls_py/repl.py
@@ -24,9 +24,9 @@ def print_top_of_stack(interpreter: InterpreterState) -> None:
         print(f"#0: {item.value}:{t}")
     elif t in {StackType.U64, StackType.U32, StackType.U16, StackType.U8}:
         print(f"#0: {item.value}:{t}")
-    elif t == StackType.F32:
+    elif t == StackType.FLOAT:
         print(f"#0: {item.value}:f32")
-    elif t == StackType.F64:
+    elif t == StackType.DOUBLE:
         print(f"#0: {item.value}")
     elif t == StackType.CHARACTER:
         print(f"#0: {item.value}")