A backend developer cover letter should typically stay between 300 and 450 words. Hiring managers prefer concise, technically focused cover letters that communicate backend impact quickly without unnecessary detail.

Yes, especially for entry-level, junior, or API-focused backend roles. GitHub repositories, deployed projects, API documentation, or portfolio links can significantly strengthen technical credibility when professional experience is limited.

Only mention technologies directly relevant to the role. Prioritize backend languages, frameworks, databases, cloud platforms, APIs, testing tools, and deployment technologies tied to actual accomplishments or systems you built.

Many recruiters skim them quickly, but engineering managers often review them more carefully, especially for mid-level and senior backend positions. A strong cover letter can help differentiate candidates with similar technical resumes.

Focus on backend projects, APIs, databases, authentication systems, deployment experience, GitHub work, bootcamp projects, or internships. Demonstrate technical initiative and backend problem-solving rather than apologizing for lack of experience.

The biggest mistake is listing technologies without explaining engineering impact. Hiring managers care far more about what you built, improved, optimized, or scaled than seeing long lists of tools without context.