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Field notes

Page 5 of 8

Build Log

Automating Product Creation With the Printify API

Automate upload, variant selection, publishing, and mockup sync while accounting for the API quirks that only appear in a production catalog.

Apr 22, 2026 / 7 min read
Build Log

How launchd Runs Our Fleet of 10 AI Agents Around the Clock

Build a lightweight scheduling and health layer with launchd, SQLite, process spawning, and three tiers of failure detection.

Apr 22, 2026 / 6 min read
Failure Files

Blast Radius Containment: What AWS Kiro Teaches About Agentic Systems

Design agent permissions so the worst possible action is recoverable, using a production-deletion incident to separate capability from containment.

Apr 21, 2026 / 5 min read
Agent Systems

Building Agent Memory That Actually Works

Build a bounded short-term notebook plus semantic long-term recall, then add the protocol that makes agents use both.

Apr 21, 2026 / 7 min read
Failure Files

HN Told Us Our SQLite Backups Were Wrong (So We Fixed It)

Trace two generations of SQLite backup failure and the verification changes that turned public technical criticism into a durable recovery process.

Apr 20, 2026 / 8 min read
Open Source Lab

We Built an AI CEO to Run Our Store β€” Now It's Yours

Inspect the state and decision architecture behind a reusable AI CEO skill, including why persistent company context matters more than the prompt.

Apr 17, 2026 / 6 min read
Build Log

Self-Hosted vs Managed Agent Infrastructure: An Honest Comparison

Compare the control, maintenance, portability, and operating tradeoffs between a self-hosted agent fleet and a managed agent platform.

Apr 16, 2026 / 6 min read
Failure Files

Your Agent Tasks Are Failing Silently β€” Here's How We Catch Them

Detect ghost claims, retry loops, missing artifacts, and stalled heartbeats before a running task can masquerade as healthy.

Apr 15, 2026 / 6 min read
Agent Systems

Why Your Agent Framework Needs Default-Deny Permissions

Replace flat, shared agent access with default-deny isolation enforced by role boundaries and filesystem scope.

Apr 14, 2026 / 5 min read
Agent Systems

Your Human-in-the-Loop Is a Rubber Stamp (Here's What We Built Instead)

Replace ceremonial approval with enforceable capability boundaries and proof of the property the reviewer was supposed to protect.

Apr 13, 2026 / 6 min read
Failure Files

How We Taught Our Agents to Survive Rate Limits

Detect provider limits, cap retries with failure budgets, and contain a retry storm to the task that caused it.

Apr 9, 2026 / 5 min read
Failure Files

Our AI Agents Lie Too β€” Here's What We Do About It

Build a trust architecture around artifacts and independent checks after agents falsely report tests, quality, and completion.

Apr 8, 2026 / 6 min read

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