Expose PL_dirty, the flag which marks global destruction

http://search.cpan.org/dist/Devel-GlobalDestruction/

Perl module which does alias lexical variables

https://metacpan.org/release/Devel-LexAlias

Perl Memory Analysis Tool

https://metacpan.org/release/Devel-MAT

Write a heap dump file for later analysis

https://metacpan.org/release/Devel-MAT-Dumper

Introspect overloaded operators

https://metacpan.org/release/Devel-OverloadInfo

Obtain the REFCNT value of a referent

https://metacpan.org/release/Devel-Refcount

Stack trace and stack trace frame objects

http://search.cpan.org/dist/Devel-StackTrace/

Perl extension to display stack trace in HTML

http://search.cpan.org/dist/Devel-StackTrace-AsHTML/

A perl5 module that dumps symbol names or the symbol table

http://search.cpan.org/dist/Devel-Symdump/

Perl interface to GSM phones/modems on serial ports

http://search.cpan.org/dist/Device-Gsm/

Perl class to interface generic modems (AT-compliant)

http://search.cpan.org/dist/Device-Modem/

Perl5 module for simple serial port control

http://search.cpan.org/dist/Device-SerialPort/

Modules that calculate message digests

http://search.cpan.org/dist/Digest/

Perl5 interface to a fingerprint in "bubble babble" format

https://metacpan.org/release/Digest-BubbleBabble

Perl5 interface to HMAC Message-Digest Algorithms

http://search.cpan.org/dist/Digest-HMAC/

Perl extension for JHash hash algorithm

https://metacpan.org/release/Digest-JHash

Perl5 interface to the MD5 algorithm

http://search.cpan.org/dist/Digest-MD5/

Perl extension for MD5 hash algorithm in pure Perl

http://search.cpan.org/dist/Digest-Perl-MD5/

Perl extension for SHA-1/224/256/384/512

http://search.cpan.org/dist/Digest-SHA/

Perl interface to the SHA-1 Algorithm

__DIR__ constant for the directory your source file is in

https://metacpan.org/release/Dir-Self

Declare version conflicts for your dist

http://search.cpan.org/dist/Dist-CheckConflicts/

Perl interface to libev, a high performance full-featured event loop

https://metacpan.org/release/EV

Unified interface to mail representations

https://metacpan.org/release/Email-Abstract

RFC 2822 Address Parsing and Creation

http://search.cpan.org/dist/Email-Address/

Parse and format RFC 2822 email addresses and groups

https://metacpan.org/release/Email-Address-XS

Produce RFC 2822 date strings

http://search.cpan.org/dist/Email-Date-Format/

Easy MIME message parsing

http://search.cpan.org/dist/Email-MIME/

Parse a MIME Content-Type Header

http://search.cpan.org/dist/Email-MIME-ContentType/

Unified interface to MIME encoding and decoding

http://search.cpan.org/dist/Email-MIME-Encodings/

Modify Email::MIME Objects Easily

http://search.cpan.org/dist/Email-MIME-Modifier/

Generate world unique message-ids

http://search.cpan.org/dist/Email-MessageID/

Email::Send - Simply Sending Email

http://search.cpan.org/dist/Email-Send/

Simple parsing of RFC2822 message format and headers

http://search.cpan.org/dist/Email-Simple/

Provides interfaces between strings and the rest of the system

http://search.cpan.org/dist/Encode/

Encode::Encoding subclass that detects the encoding of data

http://search.cpan.org/dist/Encode-Detect/

JIS X 0212 (aka JIS 2000) Encodings

https://metacpan.org/release/Encode-JIS2K

Determine the locale encoding

http://search.cpan.org/dist/Encode-Locale/

Perl module to provide Error/exception support for perl: Error

http://search.cpan.org/dist/Error/

Safely and cleanly create closures via string eval

https://metacpan.org/release/Eval-Closure

A module that allows you to declare real exception classes in Perl

http://search.cpan.org/dist/Exception-Class/

Lightweight exporting of functions and variables

https://metacpan.org/pod/Exporter::Lite

Exporter with features of Sub::Exporter but only core dependencies

https://metacpan.org/release/Exporter-Tiny

Compile and link C code for Perl modules

https://metacpan.org/release/ExtUtils-CBuilder

Wrapper for perl configuration

https://metacpan.org/release/ExtUtils-Config

Easily build XS extensions that depend on XS extensions

http://search.cpan.org/dist/ExtUtils-Depends/

Various portability utilities for module builders

https://metacpan.org/release/ExtUtils-Helpers

Build.PL install path logic made easy

https://metacpan.org/release/ExtUtils-InstallPaths

Designed to write a Makefile for an extension module

http://search.cpan.org/dist/ExtUtils-MakeMaker/

Cpanfile support for ExtUtils::MakeMaker

https://metacpan.org/release/ExtUtils-MakeMaker-CPANfile