diff --git a/CHANGELOG b/CHANGELOG
index 03f7511d..aaab44a3 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,6 +1,7 @@
 jc changelog
 
 20220601 v1.20.1 (in progress)
+- Add `postconf -M` parser tested on linux
 - Fix `id` parser for cases where the user or group name is not present
 
 20220531 v1.20.0
diff --git a/jc/parsers/postconf.py b/jc/parsers/postconf.py
index 15eadd62..d0a318f1 100644
--- a/jc/parsers/postconf.py
+++ b/jc/parsers/postconf.py
@@ -17,12 +17,22 @@ Schema:
 
     [
       {
-        "postconf":     string,
-        "bar":     boolean,
-        "baz":     integer
+        "service_name":                     string,
+        "service_type":                     string,
+        "private":                          boolean/null,  # [0]
+        "unprivileged":                     boolean/null,  # [0]
+        "chroot":                           boolean/null,  # [0]
+        "wake_up_time":                     integer,       # [1]
+        "no_wake_up_before_first_use":      boolean/null,  # [2]
+        "process_limit":                    integer,
+        "command":                          string
       }
     ]
 
+    [0] '-' converted to null/None
+    [1] '-' converted to -1
+    [2] null/None if `wake_up_time` is null/None
+
 Examples:
 
     $ postconf | jc --postconf -p