Author profile
Caleb Geene
Director, Site Reliability Engineering
Caleb Geene is Director of Site Reliability Engineering at Nylas, with more than a decade of experience spanning support, sales engineering, software engineering, and SRE leadership. He led the work that raised the Nylas API SLA from 99.9% to 99.99% through canary analysis and continuous chaos testing, and has scaled products to 10 million daily active users. He works primarily in Kubernetes, AWS, GCP, and Python. His guides cover operational guardrails, secure agent access, and the failure modes that matter when email automation reaches production.
Areas of expertise
- Site Reliability
- Infrastructure
- Kubernetes
- DevOps
- Cloud Architecture
Profiles
Guides on this site
- mbsync vs Nylas: IMAP sync vs email API
mbsync (isync) syncs IMAP mailboxes to local Maildir for mutt or neomutt. Compare its sync model, Gmail OAuth setup, and where an API email CLI skips it.
- Why Cloud Servers Block SMTP Ports
AWS, GCP, and Azure block outbound SMTP port 25 while ports 587 and 465 stay open. Confirm the block and send email over an HTTPS API instead.
- Build a BeeAI Email Agent
Give a BeeAI ReAct agent email by wrapping the Nylas CLI in a custom tool — one subprocess call per action, JSON in and out, across 6 providers, no SDK.
- Build a MetaGPT Email Agent
Give a MetaGPT role email by wrapping the Nylas CLI in an Action — one subprocess per action, JSON in and out, across six providers, with no provider SDK.
- Build an Incident-Response Email Agent
An AI agent ingests alert emails, classifies severity, acknowledges each, escalates the urgent ones to on-call, and keeps a clean timeline of every incident.
- Build an Out-of-Office Coverage Agent
An AI agent covers a mailbox while someone is away: it auto-replies, flags what's urgent, escalates time-sensitive mail to a backup, and logs the rest.
- Multi-Tenant Agent Inboxes
Give every SaaS customer its own AI agent inbox. How to address, route, and isolate one managed mailbox per tenant — and when a shared inbox is enough.
- SavvyCal vs Nylas: Scheduling Compared
SavvyCal is a scheduling SaaS for end users. Nylas is the API and CLI for building scheduling into your product across Google, Microsoft, and iCloud calendars.
- Apideck vs Nylas: Unified API Compared
Apideck covers CRM, HRIS, accounting, and 9+ API categories. Nylas goes deep on email, calendar, and contacts with agent containment and an open-source CLI.
- Build an Appointment-Reminder Agent
Build an appointment-reminder agent with Nylas CLI: poll the calendar, send T-24h and T-1h reminder emails, and process reply confirmations to cut no-shows.
- Calendar Analytics from the Terminal
Measure meeting load from the terminal with calendar analytics. Count total hours, recurring vs one-off meetings, and busiest days using jq and Nylas CLI.
- Build a Letta (MemGPT) Email Agent
Give a Letta agent email: register a custom tool that calls the Nylas CLI, so it reads Gmail threads in JSON and remembers senders and threads across sessions.