diff --git a/elements/neuron/appunti/old/simple_interpreter/example.snip b/elements/neuron/appunti/old/simple_interpreter/example.snip
new file mode 100644
index 0000000..0099244
--- /dev/null
+++ b/elements/neuron/appunti/old/simple_interpreter/example.snip
@@ -0,0 +1,40 @@
+# example.snip — demonstrates the Snippet language
+
+snippet init
+    set x = 5
+    set y = 10
+    print x
+    print y
+
+snippet adjust_x
+    # If x is small, bump it up; otherwise pull it back down
+    if x < 8
+        increase x
+        increase x
+        increase x
+        if x > 6
+            increase x
+        else
+            decrease x
+    else
+        decrease x
+    print x
+
+snippet adjust_y
+    if y > 8
+        decrease y
+        if y > 5
+            decrease y
+            decrease y
+        else
+            increase y
+    else
+        increase y
+    print y
+
+snippet final
+    # Both snippets share variables — x and y from above are visible here
+    if x > 7
+        print x
+    else
+        print y
diff --git a/elements/neuron/appunti/old/simple_interpreter/interpreter.py b/elements/neuron/appunti/old/simple_interpreter/interpreter.py
new file mode 100644
index 0000000..a6e6bb5
--- /dev/null
+++ b/elements/neuron/appunti/old/simple_interpreter/interpreter.py
@@ -0,0 +1,480 @@
+#!/usr/bin/env python3
+"""
+╔══════════════════════════════════════════════════════════════╗
+║              S N I P P E T   L A N G U A G E                ║
+║                     Interpreter v1.0                         ║
+╠══════════════════════════════════════════════════════════════╣
+║  Syntax:                                                     ║
+║    snippet <name>                                            ║
+║        set <var> = <number>    # assign a variable           ║
+║        increase <var>          # var += 1                    ║
+║        decrease <var>          # var -= 1                    ║
+║        print <var>             # print variable value        ║
+║        if <var> > <number>     # conditional (> or <)        ║
+║            ...                                               ║
+║            else                                              ║
+║                ...                                           ║
+║                                                              ║
+║  Rules:                                                      ║
+║    • Snippets run top-to-bottom and share all variables      ║
+║    • Indentation defines scope (spaces or tabs, be consistent)
+║    • No loops                                                ║
+║    • Numbers only (integers and decimals)                    ║
+║    • Lines starting with # are comments                      ║
+╚══════════════════════════════════════════════════════════════╝
+
+Usage:
+    python interpreter.py program.snip    # run a file
+    python interpreter.py                 # REPL (blank line to run)
+"""
+
+import sys
+import re
+from dataclasses import dataclass
+from typing import Any, Dict, List, Optional, Tuple
+
+
+# ══════════════════════════════════════════════════════════════
+#  TOKEN TYPES
+# ══════════════════════════════════════════════════════════════
+
+class TT:
+    SNIPPET  = 'SNIPPET'
+    IF       = 'IF'
+    ELSE     = 'ELSE'
+    INCREASE = 'INCREASE'
+    DECREASE = 'DECREASE'
+    SET      = 'SET'
+    PRINT    = 'PRINT'
+    NAME     = 'NAME'
+    NUMBER   = 'NUMBER'
+    GT       = 'GT'
+    LT       = 'LT'
+    EQ       = 'EQ'
+
+KEYWORDS: Dict[str, str] = {
+    'snippet':  TT.SNIPPET,
+    'if':       TT.IF,
+    'else':     TT.ELSE,
+    'increase': TT.INCREASE,
+    'decrease': TT.DECREASE,
+    'set':      TT.SET,
+    'print':    TT.PRINT,
+}
+
+
+@dataclass
+class Token:
+    type:  str
+    value: Any
+    line:  int
+
+    def __repr__(self) -> str:
+        return f"Token({self.type}, {self.value!r}, line={self.line})"
+
+
+# ══════════════════════════════════════════════════════════════
+#  LEXER  →  list of (indent, [Token …], line_num)
+# ══════════════════════════════════════════════════════════════
+
+class LexerError(Exception):
+    pass
+
+
+class Lexer:
+    def __init__(self, source: str):
+        self.source = source
+
+    def tokenize(self) -> List[Tuple[int, List[Token], int]]:
+        result: List[Tuple[int, List[Token], int]] = []
+        for line_num, raw in enumerate(self.source.splitlines(), 1):
+            stripped = raw.rstrip()
+            if not stripped or stripped.lstrip().startswith('#'):
+                continue
+            indent = len(raw) - len(raw.lstrip(' \t'))
+            tokens = self._lex_words(stripped.lstrip().split(), line_num)
+            if tokens:
+                result.append((indent, tokens, line_num))
+        return result
+
+    def _lex_words(self, words: List[str], line_num: int) -> List[Token]:
+        tokens: List[Token] = []
+        for word in words:
+            if word in KEYWORDS:
+                tokens.append(Token(KEYWORDS[word], word, line_num))
+            elif re.fullmatch(r'-?\d+(\.\d+)?', word):
+                tokens.append(Token(TT.NUMBER, float(word), line_num))
+            elif word == '>':
+                tokens.append(Token(TT.GT, '>', line_num))
+            elif word == '<':
+                tokens.append(Token(TT.LT, '<', line_num))
+            elif word == '=':
+                tokens.append(Token(TT.EQ, '=', line_num))
+            elif re.fullmatch(r'[a-zA-Z_]\w*', word):
+                tokens.append(Token(TT.NAME, word, line_num))
+            else:
+                raise LexerError(f"[Line {line_num}] Unknown token: {word!r}")
+        return tokens
+
+
+# ══════════════════════════════════════════════════════════════
+#  AST  NODES
+# ══════════════════════════════════════════════════════════════
+
+@dataclass
+class ProgramNode:
+    snippets: List
+
+@dataclass
+class SnippetNode:
+    name: str
+    body: List
+    line: int
+
+@dataclass
+class ConditionNode:
+    left:  str    # variable name
+    op:    str    # '>' or '<'
+    right: float  # literal number
+    line:  int
+
+@dataclass
+class IfNode:
+    condition: ConditionNode
+    then_body: List
+    else_body: List
+    line: int
+
+@dataclass
+class IncreaseNode:
+    name: str
+    line: int
+
+@dataclass
+class DecreaseNode:
+    name: str
+    line: int
+
+@dataclass
+class SetNode:
+    name:  str
+    value: float
+    line:  int
+
+@dataclass
+class PrintNode:
+    name: str
+    line: int
+
+
+# ══════════════════════════════════════════════════════════════
+#  PARSER
+# ══════════════════════════════════════════════════════════════
+
+class ParseError(Exception):
+    pass
+
+
+# Shorthand type for a lexed line
+LexLine = Tuple[int, List[Token], int]
+
+
+class Parser:
+    def __init__(self, lines: List[LexLine]):
+        self.lines = lines
+        self.pos   = 0
+
+    # ── low-level helpers ─────────────────────────────────────
+
+    def _peek(self) -> Optional[LexLine]:
+        return self.lines[self.pos] if self.pos < len(self.lines) else None
+
+    def _consume(self) -> LexLine:
+        line = self.lines[self.pos]
+        self.pos += 1
+        return line
+
+    # ── top level ─────────────────────────────────────────────
+
+    def parse(self) -> ProgramNode:
+        snippets = []
+        while self._peek():
+            indent, tokens, line_num = self._peek()
+            if tokens[0].type != TT.SNIPPET:
+                raise ParseError(
+                    f"[Line {line_num}] Expected 'snippet', got {tokens[0].value!r}"
+                )
+            snippets.append(self._parse_snippet())
+        return ProgramNode(snippets)
+
+    # ── snippet ───────────────────────────────────────────────
+
+    def _parse_snippet(self) -> SnippetNode:
+        indent, tokens, line_num = self._consume()
+        if len(tokens) < 2 or tokens[1].type != TT.NAME:
+            raise ParseError(f"[Line {line_num}] Expected a name after 'snippet'")
+        name = tokens[1].value
+        body = self._parse_block(parent_indent=indent)
+        if not body:
+            raise ParseError(f"[Line {line_num}] Snippet '{name}' has an empty body")
+        return SnippetNode(name, body, line_num)
+
+    # ── block ─────────────────────────────────────────────────
+
+    def _parse_block(self, parent_indent: int) -> List:
+        """
+        Collect statements whose indentation is strictly greater than
+        parent_indent and all equal to the first line's indentation.
+        """
+        nxt = self._peek()
+        if nxt is None or nxt[0] <= parent_indent:
+            return []
+
+        block_indent = nxt[0]
+        stmts = []
+
+        while True:
+            nxt = self._peek()
+            if nxt is None or nxt[0] < block_indent:
+                break
+            indent, tokens, line_num = nxt
+            if indent > block_indent:
+                raise ParseError(
+                    f"[Line {line_num}] Unexpected indentation "
+                    f"(expected {block_indent}, got {indent})"
+                )
+            if tokens[0].type == TT.ELSE:
+                break  # parent if-parser will handle this
+            stmts.append(self._parse_statement(block_indent))
+
+        return stmts
+
+    # ── statements ────────────────────────────────────────────
+
+    def _parse_statement(self, block_indent: int):
+        indent, tokens, line_num = self._peek()
+        tt = tokens[0].type
+        dispatch = {
+            TT.IF:       self._parse_if,
+            TT.INCREASE: self._parse_increase,
+            TT.DECREASE: self._parse_decrease,
+            TT.SET:      self._parse_set,
+            TT.PRINT:    self._parse_print,
+        }
+        if tt not in dispatch:
+            raise ParseError(
+                f"[Line {line_num}] Unexpected keyword: {tokens[0].value!r}"
+            )
+        return dispatch[tt](block_indent) if tt == TT.IF else dispatch[tt]()
+
+    def _parse_if(self, current_indent: int) -> IfNode:
+        indent, tokens, line_num = self._consume()
+        # Expected shape:  IF  NAME  (GT|LT)  NUMBER
+        if len(tokens) < 4:
+            raise ParseError(f"[Line {line_num}] Incomplete 'if' condition")
+        if tokens[1].type != TT.NAME:
+            raise ParseError(f"[Line {line_num}] Expected variable name after 'if'")
+        if tokens[2].type not in (TT.GT, TT.LT):
+            raise ParseError(f"[Line {line_num}] Expected '>' or '<' in condition")
+        if tokens[3].type != TT.NUMBER:
+            raise ParseError(f"[Line {line_num}] Expected a number in condition")
+
+        cond = ConditionNode(
+            left  = tokens[1].value,
+            op    = tokens[2].value,
+            right = tokens[3].value,
+            line  = line_num,
+        )
+        then_body = self._parse_block(parent_indent=indent)
+
+        # Optional else at the SAME indent level as the if
+        else_body: List = []
+        nxt = self._peek()
+        if nxt and nxt[0] == indent and nxt[1][0].type == TT.ELSE:
+            self._consume()  # eat 'else'
+            else_body = self._parse_block(parent_indent=indent)
+
+        return IfNode(cond, then_body, else_body, line_num)
+
+    def _parse_increase(self) -> IncreaseNode:
+        indent, tokens, line_num = self._consume()
+        if len(tokens) < 2 or tokens[1].type != TT.NAME:
+            raise ParseError(f"[Line {line_num}] Expected variable name after 'increase'")
+        return IncreaseNode(tokens[1].value, line_num)
+
+    def _parse_decrease(self) -> DecreaseNode:
+        indent, tokens, line_num = self._consume()
+        if len(tokens) < 2 or tokens[1].type != TT.NAME:
+            raise ParseError(f"[Line {line_num}] Expected variable name after 'decrease'")
+        return DecreaseNode(tokens[1].value, line_num)
+
+    def _parse_set(self) -> SetNode:
+        indent, tokens, line_num = self._consume()
+        # set  NAME  =  NUMBER
+        if len(tokens) < 4:
+            raise ParseError(f"[Line {line_num}] Syntax: set <var> = <number>")
+        if tokens[1].type != TT.NAME:
+            raise ParseError(f"[Line {line_num}] Expected variable name after 'set'")
+        if tokens[2].type != TT.EQ:
+            raise ParseError(f"[Line {line_num}] Expected '=' after variable name")
+        if tokens[3].type != TT.NUMBER:
+            raise ParseError(f"[Line {line_num}] Expected a number after '='")
+        return SetNode(tokens[1].value, tokens[3].value, line_num)
+
+    def _parse_print(self) -> PrintNode:
+        indent, tokens, line_num = self._consume()
+        if len(tokens) < 2 or tokens[1].type != TT.NAME:
+            raise ParseError(f"[Line {line_num}] Expected variable name after 'print'")
+        return PrintNode(tokens[1].value, line_num)
+
+
+# ══════════════════════════════════════════════════════════════
+#  INTERPRETER  (tree-walk evaluator)
+# ══════════════════════════════════════════════════════════════
+
+class SnippetRuntimeError(Exception):
+    pass
+
+
+class Interpreter:
+    def __init__(self):
+        # All snippets share this variable store
+        self.variables: Dict[str, float] = {}
+
+    def run(self, program: ProgramNode) -> None:
+        for snippet in program.snippets:
+            self._exec_snippet(snippet)
+
+    # ── snippet ───────────────────────────────────────────────
+
+    def _exec_snippet(self, node: SnippetNode) -> None:
+        print(f"── snippet {node.name} ──")
+        self._exec_block(node.body)
+
+    # ── block / dispatch ──────────────────────────────────────
+
+    def _exec_block(self, stmts: List) -> None:
+        for stmt in stmts:
+            self._exec(stmt)
+
+    def _exec(self, node) -> None:
+        dispatch = {
+            IfNode:       self._exec_if,
+            IncreaseNode: self._exec_increase,
+            DecreaseNode: self._exec_decrease,
+            SetNode:      self._exec_set,
+            PrintNode:    self._exec_print,
+        }
+        handler = dispatch.get(type(node))
+        if handler is None:
+            raise SnippetRuntimeError(f"Unknown AST node: {type(node).__name__}")
+        handler(node)
+
+    # ── statements ────────────────────────────────────────────
+
+    def _exec_if(self, node: IfNode) -> None:
+        if self._eval_condition(node.condition):
+            self._exec_block(node.then_body)
+        else:
+            self._exec_block(node.else_body)
+
+    def _eval_condition(self, cond: ConditionNode) -> bool:
+        val = self._get_var(cond.left, cond.line)
+        if cond.op == '>':
+            return val > cond.right
+        if cond.op == '<':
+            return val < cond.right
+        raise SnippetRuntimeError(f"Unknown operator: {cond.op!r}")
+
+    def _exec_increase(self, node: IncreaseNode) -> None:
+        self.variables[node.name] = self._get_var(node.name, node.line) + 1
+
+    def _exec_decrease(self, node: DecreaseNode) -> None:
+        self.variables[node.name] = self._get_var(node.name, node.line) - 1
+
+    def _exec_set(self, node: SetNode) -> None:
+        self.variables[node.name] = node.value
+
+    def _exec_print(self, node: PrintNode) -> None:
+        val = self._get_var(node.name, node.line)
+        # Show as int when the value is a whole number
+        display = int(val) if val == int(val) else val
+        print(f"  {node.name} = {display}")
+
+    # ── helpers ───────────────────────────────────────────────
+
+    def _get_var(self, name: str, line: int) -> float:
+        if name not in self.variables:
+            raise SnippetRuntimeError(
+                f"[Line {line}] Undefined variable: '{name}'"
+            )
+        return self.variables[name]
+
+
+# ══════════════════════════════════════════════════════════════
+#  PUBLIC ENTRY POINT
+# ══════════════════════════════════════════════════════════════
+
+def run_source(source: str) -> None:
+    """Lex → parse → interpret a source string."""
+    try:
+        lines  = Lexer(source).tokenize()
+        ast    = Parser(lines).parse()
+        Interpreter().run(ast)
+    except (LexerError, ParseError, SnippetRuntimeError) as err:
+        print(f"\n  ✖  {err}", file=sys.stderr)
+        sys.exit(1)
+
+
+# ══════════════════════════════════════════════════════════════
+#  COMMAND LINE
+# ══════════════════════════════════════════════════════════════
+
+REPL_BANNER = """\
+╔════════════════════════════════╗
+║  Snippet Language REPL  v1.0   ║
+║  blank line → run              ║
+║  'exit'     → quit             ║
+╚════════════════════════════════╝
+"""
+
+def _repl() -> None:
+    print(REPL_BANNER)
+    while True:
+        collected: List[str] = []
+        prompt = '> '
+        try:
+            while True:
+                line = input(prompt)
+                if line.strip().lower() == 'exit':
+                    sys.exit(0)
+                if line == '' and collected:
+                    break
+                collected.append(line)
+                prompt = '  '
+        except EOFError:
+            break
+        if collected:
+            run_source('\n'.join(collected))
+            print()
+
+
+def main() -> None:
+    if len(sys.argv) == 1:
+        _repl()
+    elif len(sys.argv) == 2:
+        path = sys.argv[1]
+        try:
+            with open(path) as fh:
+                source = fh.read()
+        except FileNotFoundError:
+            print(f"File not found: {path}", file=sys.stderr)
+            sys.exit(1)
+        run_source(source)
+    else:
+        print(f"Usage: {sys.argv[0]} [file.snip]", file=sys.stderr)
+        sys.exit(1)
+
+
+if __name__ == '__main__':
+    main()