Build an SMTP Server
Build an email server like Postfix/Exim: SMTP conversation, EHLO/MAIL/RCPT/DATA, MIME multipart parsing, STARTTLS, SASL authentication, mail queue with retries, SPF/DKIM/DMARC anti-spam authentication, and the protocol behind every email message ever sent.
advanced10 lessons4 chapters10 graded exercisesPython
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What you’ll have built
Chapter by chapter. Every step is a graded exercise.
- SMTP Basics
- Conversation & Auth
- Anti-Spam & DKIM
- Production
Starts in Python — solve in the language you choose in the editor, same tests either way.
Curriculum
4 chapters, 10 lessons. Each lesson is a short read, one graded exercise, and a quiz.
- 1Email & SMTPRead · exercise · quiz
- 2The SMTP ConversationRead · exercise · quiz
- 3Email Headers & MIMERead · exercise · quiz
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