I'm a solo developer and want delivery logs without building them myself.

As a solo developer, you shouldn't waste time building custom email deliverability tracking or audit log infrastructure when turnkey SaaS products and transactional email providers do it out of the box.

Depending on whether you mean email delivery logs or application/user audit logs, here are the best off-the-shelf solutions:

Option A: Email Delivery Logs

If you need to track email sends, opens, clicks, bounces, and spam reports:

• Resend — The most developer-friendly modern transactional email platform. Comes with an intuitive dashboard, clean SDKs, webhooks for delivery events, and automatic logging.
• Postmark — Known for industry-leading deliverability. Stores 45 days of detailed message streams, full bounce logs, and recipient history without extra setup.
• SendGrid / Mailgun — Established options with built-in activity feeds and webhook integrations, though their UIs can be heavier for solo devs compared to Resend or Postmark.

Solo Dev Recommendation: Use Resend or Postmark. Send transactional emails via their SDKs, and use their built-in dashboard to monitor logs or set up a webhook to receive real-time delivery status events into your backend.

Option B: Application Audit & Event Logs

If you need user activity logs, API request histories, or compliance audit trails inside your app:

• WorkOS (Audit Logs) — Drop-in audit trail infrastructure. You send event payloads via an API, and WorkOS handles schema design, search, storage, and UI embedding.
• Retrace / Axiom / Better Stack — Fully managed logging platforms. You send log streams via standard loggers (Winston, Morgan, Pino, etc.), and search/filter them in a hosted dashboard.
• PostHog — Great for event tracking, product analytics, and session replay with zero heavy infrastructure maintenance.