DeepSeek PR Security Review in n8n with GitHub Status & Gmail Alerts

Stop risky PRs before they land—DeepSeek security reviews with GitHub status + Gmail alerts

This n8n workflow automatically reviews every GitHub pull request using DeepSeek. It analyzes the PR diff, flags potential hardcoded secrets and risky code, posts an actionable GitHub status check, comments inline on the exact lines, and emails the verdict via Gmail.

What this workflow does

• Triggers on PR activity: runs when a pull request is opened or synchronized (updated).
• Fetches and formats the diff: pulls the PR’s unified diff, truncates it to fit model context, and includes PR metadata (title, author, repository).
• Runs a strict DeepSeek review: sends the formatted diff to DeepSeek through a LangChain agent, requiring a strict JSON output with:
  • a verdict
  • an issue list (including file + line)
  • a summary
• Publishes results to GitHub: posts a commit status to the PR’s head SHA using the ai-pr-reviewer context. Pass marks success; all other verdicts fail.
• Comments on the PR: adds a summary comment with verdict, findings, and issue count.
• Inline code review comments: when issues are present, converts file/line hints into diff positions and posts inline review comments on the flagged lines.
• Email notification via Gmail: routes by verdict (blocked / needs_changes / pass) and sends a Gmail message containing the summary and issues.

Use cases

• SaaS teams that want security reviewer coverage for every PR without adding manual burden.
• Automation engineers enforcing “no secrets in code” by catching hardcoded secrets early.
• Teams needing fast, consistent PR security signals with GitHub status checks and email alerts.

Technical details

• Integrations: GitHub (PRs, diff, commit status, PR comments) and Gmail (email notifications).
• n8n nodes / building blocks: if, code, gmail, github, switch, and sticky note.
• Model interaction: DeepSeek via a LangChain agent with enforced JSON parsing (verdict + issue list + summary).