diff --git a/tools/generate-wire.py b/tools/generate-wire.py
index ee0a5ce95..e5489ea7f 100755
--- a/tools/generate-wire.py
+++ b/tools/generate-wire.py
@@ -248,6 +248,31 @@ towire_impl_templ = """u8 *towire_{name}(const tal_t *ctx{args})
 }}
 """
 
+towire_tlv_templ = """u8 *towire_{name}(const tal_t *ctx{args})
+{{
+{field_decls}
+\tu8 *p = tal_arr(ctx, u8, 0);
+\ttowire_u16(&p, {enumname});
+\ttowire_u16(&p, {len});
+{subcalls}
+
+\treturn memcheck(p, tal_count(p));
+}}
+"""
+
+fromwire_tlv_templ = """bool frowire_{name}({ctx}const void *p{args})
+{{
+{fields}
+\tconst u8 *cursor = p;
+\tsize_t plen = tal_count(p);
+
+\tif (frmwire_u16(&cursor, &plen) != {enum.name})
+\t\treturn false;
+{subcalls}
+\treturn cursor != NULL;
+}}
+"""
+
 printwire_header_templ = """void printwire_{name}(const char *fieldname, const u8 *cursor);
 """
 printwire_impl_templ = """void printwire_{name}(const char *fieldname, const u8 *cursor)
@@ -739,7 +764,7 @@ for line in fileinput.input(options.files):
         comments = []
 
 
-def construct_enums(msgs):
+def construct_hdr_enums(msgs):
     enums = ""
     for m in msgs:
         for c in m.comments:
@@ -748,19 +773,39 @@ def construct_enums(msgs):
     return enums
 
 
+def construct_impl_enums(msgs):
+    return '\n\t'.join(['case {enum.name}: return "{enum.name}";'.format(enum=m.enum) for m in msgs])
+
+
 def enum_header(enums, enumname):
-    return enum_header_template.format(
+    return format_enums(enum_header_template, enums, enumname)
+
+
+def enum_impl(enums, enumname):
+    return format_enums(enum_impl_template, enums, enumname)
+
+
+def format_enums(template, enums, enumname):
+    return template.format(
         enums=enums,
         enumname=enumname)
 
 
-def build_enums(toplevel_enumname, toplevel_enums, tlv_fields):
+def build_hdr_enums(toplevel_enumname, messages, tlv_fields):
     enum_set = ""
-    enum_set += enum_header(toplevel_enums, toplevel_enumname)
+    enum_set += enum_header(construct_hdr_enums(messages), toplevel_enumname)
     for field_name, messages in tlv_fields.items():
         enum_set += "\n"
-        enums = construct_enums(messages)
-        enum_set += enum_header(enums, field_name + '_type')
+        enum_set += enum_header(construct_hdr_enums(messages), field_name + '_type')
+    return enum_set
+
+
+def build_impl_enums(toplevel_enumname, messages, tlv_fields):
+    enum_set = ""
+    enum_set += enum_impl(construct_impl_enums(messages), toplevel_enumname)
+    for field_name, messages in tlv_fields.items():
+        enum_set += "\n"
+        enum_set += enum_impl(construct_impl_enums(messages), field_name + '_type')
     return enum_set
 
 
@@ -770,6 +815,20 @@ enum_header_template = """enum {enumname} {{
 const char *{enumname}_name(int e);
 """
 
+enum_impl_template = """
+const char *{enumname}_name(int e)
+{{
+\tstatic char invalidbuf[sizeof("INVALID ") + STR_MAX_CHARS(e)];
+
+\tswitch ((enum {enumname})e) {{
+\t{enums}
+\t}}
+
+\tsnprintf(invalidbuf, sizeof(invalidbuf), "INVALID %i", e);
+\treturn invalidbuf;
+}}
+"""
+
 header_template = """/* This file was generated by generate-wire.py */
 /* Do not modify this file! Modify the _csv file it was generated from. */
 #ifndef LIGHTNING_{idem}
@@ -777,7 +836,7 @@ header_template = """/* This file was generated by generate-wire.py */
 #include <ccan/tal/tal.h>
 #include <wire/wire.h>
 {includes}
-{formatted_enums}
+{formatted_hdr_enums}
 {func_decls}
 #endif /* LIGHTNING_{idem} */
 """
@@ -788,19 +847,7 @@ impl_template = """/* This file was generated by generate-wire.py */
 #include <ccan/mem/mem.h>
 #include <ccan/tal/str/str.h>
 #include <stdio.h>
-
-const char *{enumname}_name(int e)
-{{
-\tstatic char invalidbuf[sizeof("INVALID ") + STR_MAX_CHARS(e)];
-
-\tswitch ((enum {enumname})e) {{
-\t{cases}
-\t}}
-
-\tsnprintf(invalidbuf, sizeof(invalidbuf), "INVALID %i", e);
-\treturn invalidbuf;
-}}
-
+{formatted_impl_enums}
 {func_decls}
 """
 
@@ -850,10 +897,9 @@ else:
     template = impl_template
 
 # Dump out enum, sorted by value order.
-enums = construct_enums(messages)
-built_enums = build_enums(options.enumname, enums, tlv_fields)
+built_hdr_enums = build_hdr_enums(options.enumname, messages, tlv_fields)
+built_impl_enums = build_impl_enums(options.enumname, messages, tlv_fields)
 includes = '\n'.join(includes)
-cases = ['case {enum.name}: return "{enum.name}";'.format(enum=m.enum) for m in messages]
 printcases = ['case {enum.name}: printf("{enum.name}:\\n"); printwire_{name}("{name}", msg); return;'.format(enum=m.enum, name=m.name) for m in messages]
 
 if options.printwire:
@@ -865,11 +911,10 @@ else:
 
 print(template.format(
     headerfilename=options.headerfilename,
-    cases='\n\t'.join(cases),
     printcases='\n\t'.join(printcases),
     idem=idem,
     includes=includes,
     enumname=options.enumname,
-    enums=enums,
-    formatted_enums=built_enums,
+    formatted_hdr_enums=built_hdr_enums,
+    formatted_impl_enums=built_impl_enums,
     func_decls='\n'.join(decls)))