Parse and format strp and strf time patterns

https://metacpan.org/release/DateTime-Format-Strptime

Parse and format W3CDTF datetime strings

http://datetime.perl.org/

Create DateTime objects with sub-second current time resolution

https://metacpan.org/release/DateTime-HiRes

Localization support for DateTime

https://metacpan.org/release/DateTime-Locale

Time zone object base class and factory

https://metacpan.org/release/DateTime-TimeZone

Declarative Validation of Perl Data Structures

https://metacpan.org/release/Declare-Constraints-Simple

Figure out the names of variables passed into subroutines

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

Custom op checking attached to subroutines

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

Perl module which is meatier versions of caller

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

Check that a command is available

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

Check the compiler availability

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

Check that a library is available

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

Find memory cycles in objects

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

Adding keywords to Perl, in Perl

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

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/

Perl5 module that dumps symbol names or the symbol table

https://metacpan.org/release/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)

https://metacpan.org/release/Device-Modem

Perl5 module for simple serial port control

https://metacpan.org/release/Device-SerialPort

Modules that calculate message digests

https://metacpan.org/release/Digest

Perl5 interface to a fingerprint in "bubble babble" format

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

Perl5 interface to HMAC Message-Digest Algorithms

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

Perl extension for JHash hash algorithm

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

Perl5 interface to the MD5 algorithm

https://metacpan.org/release/Digest-MD5

Perl extension for MD5 hash algorithm in pure Perl

https://metacpan.org/release/Digest-Perl-MD5

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

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

Perl interface to the SHA-1 Algorithm

Perl extension for SHA-3

https://metacpan.org/pod/Digest::SHA3

__DIR__ constant for the directory your source file is in

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

Declare version conflicts for your dist

https://metacpan.org/release/Dist-CheckConflicts

Deconstructed dynamic C library loading

https://metacpan.org/release/DynaLoader-Functions

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

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

Parse and format RFC 2822 email addresses and groups

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

Produce RFC 2822 date strings

https://metacpan.org/release/Email-Date-Format

Easy MIME message parsing

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

Parse a MIME Content-Type Header

https://metacpan.org/release/Email-MIME-ContentType

Unified interface to MIME encoding and decoding

https://metacpan.org/release/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/

Read e-mail messages stored as .msg files

https://metacpan.org/release/Email-Outlook-Message

Email::Send - Simply Sending Email

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