diff --git a/README.md b/README.md
index 0cd022d..0e0ad48 100644
--- a/README.md
+++ b/README.md
@@ -127,12 +127,12 @@ jinjaturtle php.ini \
 ## Full usage info
 
 ```
-usage: jinjaturtle [-h] -r ROLE_NAME [-f {json,ini,toml,yaml,xml}] [-d DEFAULTS_OUTPUT] [-t TEMPLATE_OUTPUT] config
+usage: jinjaturtle [-h] -r ROLE_NAME [-f {json,ini,toml,yaml,xml,postfix,systemd}] [-d DEFAULTS_OUTPUT] [-t TEMPLATE_OUTPUT] config
 
 Convert a config file into Ansible inventory and a Jinja2 template.
 
 positional arguments:
-  config                Path to the source configuration file (TOML or INI-style).
+  config                Path to the source configuration file.
 
 options:
   -h, --help            show this help message and exit
@@ -146,6 +146,15 @@ options:
                         Path to write the Jinja2 config template. If omitted, template is printed to stdout.
 ```
 
+## Additional supported formats
+
+JinjaTurtle can also template some common "bespoke" config formats:
+
+- **Postfix main.cf** (`main.cf`) → `--format postfix`
+- **systemd unit files** (`*.service`, `*.socket`, etc.) → `--format systemd`
+
+For ambiguous extensions like `*.conf`, JinjaTurtle uses lightweight content sniffing; you can always force a specific handler via `--format`.
+
 
 ## Found a bug, have a suggestion?
 
diff --git a/pyproject.toml b/pyproject.toml
index 3ed9e59..3fc5c4a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "jinjaturtle"
-version = "0.3.5"
+version = "0.4.0"
 description = "Convert config files into Ansible defaults and Jinja2 templates."
 authors = ["Miguel Jacq <mig@mig5.net>"]
 license = "GPL-3.0-or-later"
diff --git a/src/jinjaturtle/cli.py b/src/jinjaturtle/cli.py
index e6f74ec..74fdd8e 100644
--- a/src/jinjaturtle/cli.py
+++ b/src/jinjaturtle/cli.py
@@ -42,7 +42,7 @@ def _build_arg_parser() -> argparse.ArgumentParser:
     ap.add_argument(
         "-f",
         "--format",
-        choices=["ini", "json", "toml", "yaml", "xml"],
+        choices=["ini", "json", "toml", "yaml", "xml", "postfix", "systemd"],
         help="Force config format instead of auto-detecting from filename.",
     )
     ap.add_argument(
diff --git a/src/jinjaturtle/core.py b/src/jinjaturtle/core.py
index fee5e80..d53f182 100644
--- a/src/jinjaturtle/core.py
+++ b/src/jinjaturtle/core.py
@@ -4,6 +4,7 @@ from pathlib import Path
 from typing import Any, Iterable
 
 import datetime
+import re
 import yaml
 
 from .loop_analyzer import LoopAnalyzer, LoopCandidate
@@ -14,6 +15,8 @@ from .handlers import (
     TomlHandler,
     YamlHandler,
     XmlHandler,
+    PostfixMainHandler,
+    SystemdUnitHandler,
 )
 
 
@@ -56,12 +59,18 @@ _TOML_HANDLER = TomlHandler()
 _YAML_HANDLER = YamlHandler()
 _XML_HANDLER = XmlHandler()
 
+_POSTFIX_HANDLER = PostfixMainHandler()
+_SYSTEMD_HANDLER = SystemdUnitHandler()
+
 _HANDLERS["ini"] = _INI_HANDLER
 _HANDLERS["json"] = _JSON_HANDLER
 _HANDLERS["toml"] = _TOML_HANDLER
 _HANDLERS["yaml"] = _YAML_HANDLER
 _HANDLERS["xml"] = _XML_HANDLER
 
+_HANDLERS["postfix"] = _POSTFIX_HANDLER
+_HANDLERS["systemd"] = _SYSTEMD_HANDLER
+
 
 def dump_yaml(data: Any, *, sort_keys: bool = True) -> str:
     """Dump YAML using JinjaTurtle's dumper settings.
@@ -86,24 +95,92 @@ def make_var_name(role_prefix: str, path: Iterable[str]) -> str:
     return BaseHandler.make_var_name(role_prefix, path)
 
 
+def _read_head(path: Path, max_bytes: int = 65536) -> str:
+    try:
+        with path.open("r", encoding="utf-8", errors="replace") as f:
+            return f.read(max_bytes)
+    except OSError:
+        return ""
+
+
+_SYSTEMD_SUFFIXES: set[str] = {
+    ".service",
+    ".socket",
+    ".target",
+    ".timer",
+    ".path",
+    ".mount",
+    ".automount",
+    ".slice",
+    ".swap",
+    ".scope",
+    ".link",
+    ".netdev",
+    ".network",
+}
+
+
+def _looks_like_systemd(text: str) -> bool:
+    # Be conservative: many INI-style configs have [section] and key=value.
+    # systemd unit files almost always contain one of these well-known sections.
+    if re.search(
+        r"^\s*\[(Unit|Service|Install|Socket|Timer|Path|Mount|Automount|Slice|Swap|Scope)\]\s*$",
+        text,
+        re.M,
+    ) and re.search(r"^\s*\w[\w\-]*\s*=", text, re.M):
+        return True
+    return False
+
+
 def detect_format(path: Path, explicit: str | None = None) -> str:
     """
-    Determine config format from argument or filename.
+    Determine config format.
+
+    For unambiguous extensions (json/yaml/toml/xml/ini), we rely on the suffix.
+    For ambiguous extensions like '.conf' (or no extension), we sniff the content.
     """
     if explicit:
         return explicit
+
     suffix = path.suffix.lower()
     name = path.name.lower()
+
+    # Unambiguous extensions
     if suffix == ".toml":
         return "toml"
     if suffix in {".yaml", ".yml"}:
         return "yaml"
     if suffix == ".json":
         return "json"
-    if suffix in {".ini", ".cfg", ".conf"} or name.endswith(".ini"):
-        return "ini"
     if suffix == ".xml":
         return "xml"
+
+    # Special-ish INI-like formats
+    if suffix in {".ini", ".cfg"} or name.endswith(".ini"):
+        return "ini"
+    if suffix == ".repo":
+        return "ini"
+
+    # systemd units
+    if suffix in _SYSTEMD_SUFFIXES:
+        return "systemd"
+
+    # well-known filenames
+    if name == "main.cf":
+        return "postfix"
+
+    head = _read_head(path)
+
+    # Content sniffing
+    if _looks_like_systemd(head):
+        return "systemd"
+
+    # Ambiguous .conf/.cf defaults to INI-ish if no better match
+    if suffix in {".conf", ".cf"}:
+        if name == "main.cf":
+            return "postfix"
+        return "ini"
+
     # Fallback: treat as INI-ish
     return "ini"
 
diff --git a/src/jinjaturtle/handlers/__init__.py b/src/jinjaturtle/handlers/__init__.py
index 6bbcba1..97074c5 100644
--- a/src/jinjaturtle/handlers/__init__.py
+++ b/src/jinjaturtle/handlers/__init__.py
@@ -8,6 +8,9 @@ from .toml import TomlHandler
 from .yaml import YamlHandler
 from .xml import XmlHandler
 
+from .postfix import PostfixMainHandler
+from .systemd import SystemdUnitHandler
+
 __all__ = [
     "BaseHandler",
     "DictLikeHandler",
@@ -16,4 +19,6 @@ __all__ = [
     "TomlHandler",
     "YamlHandler",
     "XmlHandler",
+    "PostfixMainHandler",
+    "SystemdUnitHandler",
 ]
diff --git a/src/jinjaturtle/handlers/postfix.py b/src/jinjaturtle/handlers/postfix.py
new file mode 100644
index 0000000..65f6be9
--- /dev/null
+++ b/src/jinjaturtle/handlers/postfix.py
@@ -0,0 +1,177 @@
+from __future__ import annotations
+
+from pathlib import Path
+from typing import Any
+
+from . import BaseHandler
+
+
+class PostfixMainHandler(BaseHandler):
+    """
+    Handler for Postfix main.cf style configuration.
+
+    Postfix main.cf is largely 'key = value' with:
+      - '#' comments
+      - continuation lines starting with whitespace (they continue the previous value)
+    """
+
+    fmt = "postfix"
+
+    def parse(self, path: Path) -> dict[str, str]:
+        text = path.read_text(encoding="utf-8")
+        return self._parse_text_to_dict(text)
+
+    def _parse_text_to_dict(self, text: str) -> dict[str, str]:
+        lines = text.splitlines()
+        out: dict[str, str] = {}
+        i = 0
+        while i < len(lines):
+            line = lines[i]
+            stripped = line.strip()
+            if not stripped or stripped.startswith("#"):
+                i += 1
+                continue
+
+            if "=" not in line:
+                i += 1
+                continue
+
+            eq_index = line.find("=")
+            key = line[:eq_index].strip()
+            if not key:
+                i += 1
+                continue
+
+            # value + inline comment
+            after = line[eq_index + 1 :]
+            value_part, _comment = self._split_inline_comment(after, {"#"})
+            value = value_part.strip()
+
+            # collect continuation lines
+            j = i + 1
+            cont_parts: list[str] = []
+            while j < len(lines):
+                nxt = lines[j]
+                if not nxt:
+                    break
+                if nxt.startswith((" ", "\t")):
+                    if nxt.strip().startswith("#"):
+                        # a commented continuation line - treat as a break
+                        break
+                    cont_parts.append(nxt.strip())
+                    j += 1
+                    continue
+                break
+
+            if cont_parts:
+                value = " ".join([value] + cont_parts).strip()
+
+            out[key] = value
+            i = j if cont_parts else i + 1
+
+        return out
+
+    def flatten(self, parsed: Any) -> list[tuple[tuple[str, ...], Any]]:
+        if not isinstance(parsed, dict):
+            raise TypeError("Postfix parse result must be a dict[str, str]")
+        items: list[tuple[tuple[str, ...], Any]] = []
+        for k, v in parsed.items():
+            items.append(((k,), v))
+        return items
+
+    def generate_jinja2_template(
+        self,
+        parsed: Any,
+        role_prefix: str,
+        original_text: str | None = None,
+    ) -> str:
+        if original_text is None:
+            # Canonical render (lossy)
+            if not isinstance(parsed, dict):
+                raise TypeError("Postfix parse result must be a dict[str, str]")
+            lines: list[str] = []
+            for k, v in parsed.items():
+                var = self.make_var_name(role_prefix, (k,))
+                lines.append(f"{k} = {{{{ {var} }}}}")
+            return "\n".join(lines).rstrip() + "\n"
+        return self._generate_from_text(role_prefix, original_text)
+
+    def _generate_from_text(self, role_prefix: str, text: str) -> str:
+        lines = text.splitlines(keepends=True)
+        out_lines: list[str] = []
+        i = 0
+        while i < len(lines):
+            raw_line = lines[i]
+            content = raw_line.rstrip("\n")
+            newline = "\n" if raw_line.endswith("\n") else ""
+
+            stripped = content.strip()
+            if not stripped:
+                out_lines.append(raw_line)
+                i += 1
+                continue
+            if stripped.startswith("#"):
+                out_lines.append(raw_line)
+                i += 1
+                continue
+
+            if "=" not in content:
+                out_lines.append(raw_line)
+                i += 1
+                continue
+
+            eq_index = content.find("=")
+            before_eq = content[:eq_index]
+            after_eq = content[eq_index + 1 :]
+
+            key = before_eq.strip()
+            if not key:
+                out_lines.append(raw_line)
+                i += 1
+                continue
+
+            # whitespace after '='
+            value_ws_len = len(after_eq) - len(after_eq.lstrip(" \t"))
+            leading_ws = after_eq[:value_ws_len]
+            value_and_comment = after_eq[value_ws_len:]
+
+            value_part, comment_part = self._split_inline_comment(
+                value_and_comment, {"#"}
+            )
+            value = value_part.strip()
+
+            # collect continuation physical lines to skip
+            j = i + 1
+            cont_parts: list[str] = []
+            while j < len(lines):
+                nxt_raw = lines[j]
+                nxt = nxt_raw.rstrip("\n")
+                if (
+                    nxt.startswith((" ", "\t"))
+                    and nxt.strip()
+                    and not nxt.strip().startswith("#")
+                ):
+                    cont_parts.append(nxt.strip())
+                    j += 1
+                    continue
+                break
+
+            if cont_parts:
+                value = " ".join([value] + cont_parts).strip()
+
+            var = self.make_var_name(role_prefix, (key,))
+            v = value
+            quoted = len(v) >= 2 and v[0] == v[-1] and v[0] in {'"', "'"}
+            if quoted:
+                replacement = (
+                    f'{before_eq}={leading_ws}"{{{{ {var} }}}}"{comment_part}{newline}'
+                )
+            else:
+                replacement = (
+                    f"{before_eq}={leading_ws}{{{{ {var} }}}}{comment_part}{newline}"
+                )
+
+            out_lines.append(replacement)
+            i = j  # skip continuation lines (if any)
+
+        return "".join(out_lines)
diff --git a/src/jinjaturtle/handlers/systemd.py b/src/jinjaturtle/handlers/systemd.py
new file mode 100644
index 0000000..044fd86
--- /dev/null
+++ b/src/jinjaturtle/handlers/systemd.py
@@ -0,0 +1,177 @@
+from __future__ import annotations
+
+from dataclasses import dataclass
+from pathlib import Path
+from typing import Any
+
+from . import BaseHandler
+
+
+@dataclass
+class SystemdLine:
+    kind: str  # 'blank' | 'comment' | 'section' | 'kv' | 'raw'
+    raw: str
+    lineno: int
+    section: str | None = None
+    key: str | None = None
+    value: str | None = None
+    comment: str = ""
+    before_eq: str = ""
+    leading_ws_after_eq: str = ""
+    occ_index: int | None = None
+
+
+@dataclass
+class SystemdUnit:
+    lines: list[SystemdLine]
+
+
+class SystemdUnitHandler(BaseHandler):
+    """
+    Handler for systemd unit files.
+
+    unit files are INI-like, but keys may repeat (e.g. multiple ExecStart= lines).
+    We preserve repeated keys by indexing them when flattening and templating.
+    """
+
+    fmt = "systemd"
+
+    def parse(self, path: Path) -> SystemdUnit:
+        text = path.read_text(encoding="utf-8")
+        return self._parse_text(text)
+
+    def _parse_text(self, text: str) -> SystemdUnit:
+        lines = text.splitlines(keepends=True)
+        out: list[SystemdLine] = []
+        current_section: str | None = None
+        # counts per section+key to assign occ_index
+        occ: dict[tuple[str, str], int] = {}
+
+        for lineno, raw_line in enumerate(lines, start=1):
+            content = raw_line.rstrip("\n")
+            stripped = content.strip()
+
+            if not stripped:
+                out.append(SystemdLine(kind="blank", raw=raw_line, lineno=lineno))
+                continue
+
+            if stripped.startswith(("#", ";")):
+                out.append(SystemdLine(kind="comment", raw=raw_line, lineno=lineno))
+                continue
+
+            # section header
+            if (
+                stripped.startswith("[")
+                and stripped.endswith("]")
+                and len(stripped) >= 2
+            ):
+                sec = stripped[1:-1].strip()
+                current_section = sec
+                out.append(
+                    SystemdLine(
+                        kind="section", raw=raw_line, lineno=lineno, section=sec
+                    )
+                )
+                continue
+
+            if "=" not in content:
+                out.append(SystemdLine(kind="raw", raw=raw_line, lineno=lineno))
+                continue
+
+            eq_index = content.find("=")
+            before_eq = content[:eq_index]
+            after_eq = content[eq_index + 1 :]
+
+            key = before_eq.strip()
+            if not key:
+                out.append(SystemdLine(kind="raw", raw=raw_line, lineno=lineno))
+                continue
+
+            # whitespace after '='
+            value_ws_len = len(after_eq) - len(after_eq.lstrip(" \t"))
+            leading_ws = after_eq[:value_ws_len]
+            value_and_comment = after_eq[value_ws_len:]
+
+            value_part, comment = self._split_inline_comment(
+                value_and_comment, {"#", ";"}
+            )
+            value = value_part.strip()
+
+            sec = current_section or "DEFAULT"
+            k = (sec, key)
+            idx = occ.get(k, 0)
+            occ[k] = idx + 1
+
+            out.append(
+                SystemdLine(
+                    kind="kv",
+                    raw=raw_line,
+                    lineno=lineno,
+                    section=sec,
+                    key=key,
+                    value=value,
+                    comment=comment,
+                    before_eq=before_eq,
+                    leading_ws_after_eq=leading_ws,
+                    occ_index=idx,
+                )
+            )
+
+        return SystemdUnit(lines=out)
+
+    def flatten(self, parsed: Any) -> list[tuple[tuple[str, ...], Any]]:
+        if not isinstance(parsed, SystemdUnit):
+            raise TypeError("systemd parse result must be a SystemdUnit")
+
+        # determine duplicates per (section,key)
+        counts: dict[tuple[str, str], int] = {}
+        for ln in parsed.lines:
+            if ln.kind == "kv" and ln.section and ln.key:
+                counts[(ln.section, ln.key)] = counts.get((ln.section, ln.key), 0) + 1
+
+        items: list[tuple[tuple[str, ...], Any]] = []
+        for ln in parsed.lines:
+            if ln.kind != "kv" or not ln.section or not ln.key:
+                continue
+            path: tuple[str, ...] = (ln.section, ln.key)
+            if counts.get((ln.section, ln.key), 0) > 1 and ln.occ_index is not None:
+                path = path + (str(ln.occ_index),)
+            items.append((path, ln.value or ""))
+        return items
+
+    def generate_jinja2_template(
+        self,
+        parsed: Any,
+        role_prefix: str,
+        original_text: str | None = None,
+    ) -> str:
+        if not isinstance(parsed, SystemdUnit):
+            raise TypeError("systemd parse result must be a SystemdUnit")
+        # We template using parsed lines so we preserve original formatting/comments.
+        counts: dict[tuple[str, str], int] = {}
+        for ln in parsed.lines:
+            if ln.kind == "kv" and ln.section and ln.key:
+                counts[(ln.section, ln.key)] = counts.get((ln.section, ln.key), 0) + 1
+
+        out_lines: list[str] = []
+        for ln in parsed.lines:
+            if ln.kind != "kv" or not ln.section or not ln.key:
+                out_lines.append(ln.raw)
+                continue
+
+            path: tuple[str, ...] = (ln.section, ln.key)
+            if counts.get((ln.section, ln.key), 0) > 1 and ln.occ_index is not None:
+                path = path + (str(ln.occ_index),)
+            var = self.make_var_name(role_prefix, path)
+
+            v = (ln.value or "").strip()
+            quoted = len(v) >= 2 and v[0] == v[-1] and v[0] in {'"', "'"}
+            if quoted:
+                repl = f'{ln.before_eq}={ln.leading_ws_after_eq}"{{{{ {var} }}}}"{ln.comment}'
+            else:
+                repl = f"{ln.before_eq}={ln.leading_ws_after_eq}{{{{ {var} }}}}{ln.comment}"
+
+            newline = "\n" if ln.raw.endswith("\n") else ""
+            out_lines.append(repl + newline)
+
+        return "".join(out_lines)
diff --git a/src/jinjaturtle/multi.py b/src/jinjaturtle/multi.py
index fb1737f..20cf544 100644
--- a/src/jinjaturtle/multi.py
+++ b/src/jinjaturtle/multi.py
@@ -36,7 +36,7 @@ SUPPORTED_SUFFIXES: dict[str, set[str]] = {
     "toml": {".toml"},
     "yaml": {".yaml", ".yml"},
     "json": {".json"},
-    "ini": {".ini", ".cfg", ".conf"},
+    "ini": {".ini", ".cfg", ".conf", ".repo"},
     "xml": {".xml"},
 }
 
@@ -584,6 +584,9 @@ class FormatOutput:
     items: list[dict[str, Any]]
 
 
+FOLDER_SUPPORTED_FORMATS: set[str] = {"json", "yaml", "toml", "ini", "xml"}
+
+
 def process_directory(
     root: Path, recursive: bool, role_prefix: str
 ) -> tuple[str, list[FormatOutput]]:
@@ -596,8 +599,14 @@ def process_directory(
     grouped: dict[str, list[tuple[Path, Any]]] = defaultdict(list)
     for p in files:
         fmt, parsed = parse_config(p, None)
+        if fmt not in FOLDER_SUPPORTED_FORMATS:
+            # Directory mode only supports a subset of formats for now.
+            continue
         grouped[fmt].append((p, parsed))
 
+    if not grouped:
+        raise ValueError(f"No folder-supported config files found under: {root}")
+
     multiple_formats = len(grouped) > 1
     outputs: list[FormatOutput] = []
 
diff --git a/tests/test_postfix_format.py b/tests/test_postfix_format.py
new file mode 100644
index 0000000..6bb9e5d
--- /dev/null
+++ b/tests/test_postfix_format.py
@@ -0,0 +1,33 @@
+from __future__ import annotations
+
+from pathlib import Path
+
+import jinjaturtle.core as core
+
+
+def test_postfix_main_cf_parsing_and_template(tmp_path: Path) -> None:
+    p = tmp_path / "main.cf"
+    p.write_text(
+        "# comment\n"
+        "myhostname = mail.example.com\n"
+        "mynetworks = 127.0.0.0/8\n"
+        "    [::1]/128\n",
+        encoding="utf-8",
+    )
+
+    fmt, parsed = core.parse_config(p)
+    assert fmt == "postfix"
+
+    flat = core.flatten_config(fmt, parsed)
+    assert (("myhostname",), "mail.example.com") in flat
+    assert any(
+        path == ("mynetworks",) and value.startswith("127.0.0.0/8")
+        for path, value in flat
+    )
+
+    template = core.generate_jinja2_template(
+        fmt, parsed, role_prefix="role", original_text=p.read_text(encoding="utf-8")
+    )
+    assert "myhostname = {{ role_myhostname }}" in template
+    assert "mynetworks = {{ role_mynetworks }}" in template
+    assert "# comment" in template
diff --git a/tests/test_systemd_format.py b/tests/test_systemd_format.py
new file mode 100644
index 0000000..c310f72
--- /dev/null
+++ b/tests/test_systemd_format.py
@@ -0,0 +1,26 @@
+from __future__ import annotations
+
+from pathlib import Path
+
+import jinjaturtle.core as core
+
+
+def test_systemd_unit_repeated_keys(tmp_path: Path) -> None:
+    p = tmp_path / "demo.service"
+    p.write_text(
+        "[Service]\n" "ExecStart=/bin/echo one\n" "ExecStart=/bin/echo two\n",
+        encoding="utf-8",
+    )
+
+    fmt, parsed = core.parse_config(p)
+    assert fmt == "systemd"
+
+    flat = core.flatten_config(fmt, parsed)
+    assert (("Service", "ExecStart", "0"), "/bin/echo one") in flat
+    assert (("Service", "ExecStart", "1"), "/bin/echo two") in flat
+
+    template = core.generate_jinja2_template(
+        fmt, parsed, role_prefix="role", original_text=p.read_text(encoding="utf-8")
+    )
+    assert "ExecStart={{ role_service_execstart_0 }}" in template
+    assert "ExecStart={{ role_service_execstart_1 }}" in template