diff --git a/src/ec_git_vsn.erl b/src/ec_git_vsn.erl
index 21d2639..f06ea8e 100644
--- a/src/ec_git_vsn.erl
+++ b/src/ec_git_vsn.erl
@@ -70,7 +70,7 @@ strip_leading_v(Vsn) ->
 -spec find_vsn_from_start_of_branch(string()) -> string().
 find_vsn_from_start_of_branch(RefTag) ->
     Count = do_cmd("git rev-list HEAD --count"),
-    erlang:iolist_to_binary("0.0.0+build.", Count, ".ref.", RefTag).
+    erlang:iolist_to_binary(["0.0.0+build.", Count, ".ref.", RefTag]).
 
 do_cmd(Cmd) ->
     trim_whitespace(os:cmd(Cmd)).
diff --git a/src/ec_semver_parser.erl b/src/ec_semver_parser.erl
index ac4ddb7..7aeeec1 100644
--- a/src/ec_semver_parser.erl
+++ b/src/ec_semver_parser.erl
@@ -1,6 +1,15 @@
 -module(ec_semver_parser).
 -export([parse/1,file/1]).
--compile({nowarn_unused_function,[p/4, p/5, p_eof/0, p_optional/1, p_not/1, p_assert/1, p_seq/1, p_and/1, p_choose/1, p_zero_or_more/1, p_one_or_more/1, p_label/2, p_string/1, p_anything/0, p_charclass/1, p_regexp/1, p_attempt/4, line/1, column/1]}).
+-define(p_anything,true).
+-define(p_charclass,true).
+-define(p_choose,true).
+-define(p_not,true).
+-define(p_one_or_more,true).
+-define(p_optional,true).
+-define(p_scan,true).
+-define(p_seq,true).
+-define(p_string,true).
+-define(p_zero_or_more,true).
 
 
 -compile(export_all).
@@ -10,34 +19,45 @@ file(Filename) -> case file:read_file(Filename) of {ok,Bin} -> parse(Bin); Err -
 -spec parse(binary() | list()) -> any().
 parse(List) when is_list(List) -> parse(list_to_binary(List));
 parse(Input) when is_binary(Input) ->
-  setup_memo(),
+  _ = setup_memo(),
   Result = case 'semver'(Input,{{line,1},{column,1}}) of
              {AST, <<>>, _Index} -> AST;
              Any -> Any
            end,
   release_memo(), Result.
 
+-spec 'semver'(input(), index()) -> parse_result().
 'semver'(Input, Index) ->
   p(Input, Index, 'semver', fun(I,D) -> (p_seq([fun 'major_minor_patch_min_patch'/2, p_optional(p_seq([p_string(<<"-">>), fun 'alpha_part'/2, p_zero_or_more(p_seq([p_string(<<".">>), fun 'alpha_part'/2]))])), p_optional(p_seq([p_string(<<"+">>), fun 'alpha_part'/2, p_zero_or_more(p_seq([p_string(<<".">>), fun 'alpha_part'/2]))])), p_not(p_anything())]))(I,D) end, fun(Node, _Idx) -> ec_semver:internal_parse_version(Node)  end).
 
+-spec 'major_minor_patch_min_patch'(input(), index()) -> parse_result().
 'major_minor_patch_min_patch'(Input, Index) ->
   p(Input, Index, 'major_minor_patch_min_patch', fun(I,D) -> (p_seq([p_choose([p_seq([p_optional(p_string(<<"v">>)), fun 'numeric_part'/2]), fun 'alpha_part'/2]), p_optional(p_seq([p_string(<<".">>), fun 'version_part'/2])), p_optional(p_seq([p_string(<<".">>), fun 'version_part'/2])), p_optional(p_seq([p_string(<<".">>), fun 'version_part'/2]))]))(I,D) end, fun(Node, Idx) ->transform('major_minor_patch_min_patch', Node, Idx) end).
 
+-spec 'version_part'(input(), index()) -> parse_result().
 'version_part'(Input, Index) ->
   p(Input, Index, 'version_part', fun(I,D) -> (p_choose([fun 'numeric_part'/2, fun 'alpha_part'/2]))(I,D) end, fun(Node, Idx) ->transform('version_part', Node, Idx) end).
 
+-spec 'numeric_part'(input(), index()) -> parse_result().
 'numeric_part'(Input, Index) ->
   p(Input, Index, 'numeric_part', fun(I,D) -> (p_one_or_more(p_charclass(<<"[0-9]">>)))(I,D) end, fun(Node, _Idx) ->erlang:list_to_integer(erlang:binary_to_list(erlang:iolist_to_binary(Node))) end).
 
+-spec 'alpha_part'(input(), index()) -> parse_result().
 'alpha_part'(Input, Index) ->
   p(Input, Index, 'alpha_part', fun(I,D) -> (p_one_or_more(p_charclass(<<"[A-Za-z0-9]">>)))(I,D) end, fun(Node, _Idx) ->erlang:iolist_to_binary(Node) end).
 
 
 transform(_,Node,_Index) -> Node.
+-file("peg_includes.hrl", 1).
+-type index() :: {{line, pos_integer()}, {column, pos_integer()}}.
+-type input() :: binary().
+-type parse_failure() :: {fail, term()}.
+-type parse_success() :: {term(), input(), index()}.
+-type parse_result() :: parse_failure() | parse_success().
+-type parse_fun() :: fun((input(), index()) -> parse_result()).
+-type xform_fun() :: fun((input(), index()) -> term()).
 
-p(Inp, Index, Name, ParseFun) ->
-  p(Inp, Index, Name, ParseFun, fun(N, _Idx) -> N end).
-
+-spec p(input(), index(), atom(), parse_fun(), xform_fun()) -> parse_result().
 p(Inp, StartIndex, Name, ParseFun, TransformFun) ->
   case get_memo(StartIndex, Name) of      % See if the current reduction is memoized
     {ok, Memo} -> %Memo;                     % If it is, return the stored result
@@ -54,12 +74,15 @@ p(Inp, StartIndex, Name, ParseFun, TransformFun) ->
       Result
   end.
 
+-spec setup_memo() -> ets:tid().
 setup_memo() ->
   put({parse_memo_table, ?MODULE}, ets:new(?MODULE, [set])).
 
+-spec release_memo() -> true.
 release_memo() ->
   ets:delete(memo_table_name()).
 
+-spec memoize(index(), atom(), parse_result()) -> true.
 memoize(Index, Name, Result) ->
   Memo = case ets:lookup(memo_table_name(), Index) of
               [] -> [];
@@ -67,6 +90,7 @@ memoize(Index, Name, Result) ->
          end,
   ets:insert(memo_table_name(), {Index, [{Name, Result}|Memo]}).
 
+-spec get_memo(index(), atom()) -> {ok, term()} | {error, not_found}.
 get_memo(Index, Name) ->
   case ets:lookup(memo_table_name(), Index) of
     [] -> {error, not_found};
@@ -77,13 +101,19 @@ get_memo(Index, Name) ->
       end
     end.
 
+-spec memo_table_name() -> ets:tid().
 memo_table_name() ->
     get({parse_memo_table, ?MODULE}).
 
+-ifdef(p_eof).
+-spec p_eof() -> parse_fun().
 p_eof() ->
   fun(<<>>, Index) -> {eof, [], Index};
      (_, Index) -> {fail, {expected, eof, Index}} end.
+-endif.
 
+-ifdef(p_optional).
+-spec p_optional(parse_fun()) -> parse_fun().
 p_optional(P) ->
   fun(Input, Index) ->
       case P(Input, Index) of
@@ -91,7 +121,10 @@ p_optional(P) ->
         {_, _, _} = Success -> Success
       end
   end.
+-endif.
 
+-ifdef(p_not).
+-spec p_not(parse_fun()) -> parse_fun().
 p_not(P) ->
   fun(Input, Index)->
       case P(Input,Index) of
@@ -100,7 +133,10 @@ p_not(P) ->
         {Result, _, _} -> {fail, {expected, {no_match, Result},Index}}
       end
   end.
+-endif.
 
+-ifdef(p_assert).
+-spec p_assert(parse_fun()) -> parse_fun().
 p_assert(P) ->
   fun(Input,Index) ->
       case P(Input,Index) of
@@ -108,27 +144,32 @@ p_assert(P) ->
         _ -> {[], Input, Index}
       end
   end.
+-endif.
 
-p_and(P) ->
-  p_seq(P).
-
+-ifdef(p_seq).
+-spec p_seq([parse_fun()]) -> parse_fun().
 p_seq(P) ->
   fun(Input, Index) ->
       p_all(P, Input, Index, [])
   end.
 
+-spec p_all([parse_fun()], input(), index(), [term()]) -> parse_result().
 p_all([], Inp, Index, Accum ) -> {lists:reverse( Accum ), Inp, Index};
 p_all([P|Parsers], Inp, Index, Accum) ->
   case P(Inp, Index) of
     {fail, _} = Failure -> Failure;
     {Result, InpRem, NewIndex} -> p_all(Parsers, InpRem, NewIndex, [Result|Accum])
   end.
+-endif.
 
+-ifdef(p_choose).
+-spec p_choose([parse_fun()]) -> parse_fun().
 p_choose(Parsers) ->
   fun(Input, Index) ->
       p_attempt(Parsers, Input, Index, none)
   end.
 
+-spec p_attempt([parse_fun()], input(), index(), none | parse_failure()) -> parse_result().
 p_attempt([], _Input, _Index, Failure) -> Failure;
 p_attempt([P|Parsers], Input, Index, FirstFailure)->
   case P(Input, Index) of
@@ -139,12 +180,18 @@ p_attempt([P|Parsers], Input, Index, FirstFailure)->
       end;
     Result -> Result
   end.
+-endif.
 
+-ifdef(p_zero_or_more).
+-spec p_zero_or_more(parse_fun()) -> parse_fun().
 p_zero_or_more(P) ->
   fun(Input, Index) ->
       p_scan(P, Input, Index, [])
   end.
+-endif.
 
+-ifdef(p_one_or_more).
+-spec p_one_or_more(parse_fun()) -> parse_fun().
 p_one_or_more(P) ->
   fun(Input, Index)->
       Result = p_scan(P, Input, Index, []),
@@ -156,7 +203,10 @@ p_one_or_more(P) ->
           {fail, {expected, {at_least_one, Failure}, Index}}
       end
   end.
+-endif.
 
+-ifdef(p_label).
+-spec p_label(atom(), parse_fun()) -> parse_fun().
 p_label(Tag, P) ->
   fun(Input, Index) ->
       case P(Input, Index) of
@@ -166,15 +216,20 @@ p_label(Tag, P) ->
           {{Tag, Result}, InpRem, NewIndex}
       end
   end.
+-endif.
 
-p_scan(_, [], Index, Accum) -> {lists:reverse( Accum ), [], Index};
+-ifdef(p_scan).
+-spec p_scan(parse_fun(), input(), index(), [term()]) -> {[term()], input(), index()}.
+p_scan(_, <<>>, Index, Accum) -> {lists:reverse(Accum), <<>>, Index};
 p_scan(P, Inp, Index, Accum) ->
   case P(Inp, Index) of
     {fail,_} -> {lists:reverse(Accum), Inp, Index};
     {Result, InpRem, NewIndex} -> p_scan(P, InpRem, NewIndex, [Result | Accum])
   end.
+-endif.
 
-p_string(S) when is_list(S) -> p_string(list_to_binary(S));
+-ifdef(p_string).
+-spec p_string(binary()) -> parse_fun().
 p_string(S) ->
     Length = erlang:byte_size(S),
     fun(Input, Index) ->
@@ -185,14 +240,20 @@ p_string(S) ->
           error:{badmatch,_} -> {fail, {expected, {string, S}, Index}}
       end
     end.
+-endif.
 
+-ifdef(p_anything).
+-spec p_anything() -> parse_fun().
 p_anything() ->
   fun(<<>>, Index) -> {fail, {expected, any_character, Index}};
      (Input, Index) when is_binary(Input) ->
           <<C/utf8, Rest/binary>> = Input,
           {<<C/utf8>>, Rest, p_advance_index(<<C/utf8>>, Index)}
   end.
+-endif.
 
+-ifdef(p_charclass).
+-spec p_charclass(string() | binary()) -> parse_fun().
 p_charclass(Class) ->
     {ok, RE} = re:compile(Class, [unicode, dotall]),
     fun(Inp, Index) ->
@@ -203,7 +264,10 @@ p_charclass(Class) ->
                 _ -> {fail, {expected, {character_class, binary_to_list(Class)}, Index}}
             end
     end.
+-endif.
 
+-ifdef(p_regexp).
+-spec p_regexp(binary()) -> parse_fun().
 p_regexp(Regexp) ->
     {ok, RE} = re:compile(Regexp, [unicode, dotall, anchored]),
     fun(Inp, Index) ->
@@ -214,13 +278,21 @@ p_regexp(Regexp) ->
             _ -> {fail, {expected, {regexp, binary_to_list(Regexp)}, Index}}
         end
     end.
+-endif.
 
+-ifdef(line).
+-spec line(index() | term()) -> pos_integer() | undefined.
 line({{line,L},_}) -> L;
 line(_) -> undefined.
+-endif.
 
+-ifdef(column).
+-spec column(index() | term()) -> pos_integer() | undefined.
 column({_,{column,C}}) -> C;
 column(_) -> undefined.
+-endif.
 
+-spec p_advance_index(input() | unicode:charlist() | pos_integer(), index()) -> index().
 p_advance_index(MatchedInput, Index) when is_list(MatchedInput) orelse is_binary(MatchedInput)-> % strings
   lists:foldl(fun p_advance_index/2, Index, unicode:characters_to_list(MatchedInput));
 p_advance_index(MatchedInput, Index) when is_integer(MatchedInput) -> % single characters