The Engineering Notebook — page 3 of 32

Notes on building with AI, agents & the modern stack.

Deep dives on AI/ML, RAG systems, agent engineering, and senior-engineer architecture decisions — a new post every week.

Hands typing on a laptop computer screen Cloud and DevOps

Postgres Full Text Search vs Elasticsearch [2026]: Pick Right

If you’re asking “do we really need Elasticsearch?”, the right answer is a reproducible benchmark plus an ops scorecard. Here’s the framework I use in 2026.

A MacBook with lines of code on its screen on a busy desk Cybersecurity

How to Implement Field-Level Redaction for RAG Pipelines [2026]

An auditor-friendly RAG privacy pattern: deterministic redaction, optional reversible tokenization, TTLs, deletion propagation, and a leakage test suite in CI.

qa checklist clipboard testing — illustration for article on How to Start an AI Agent Evaluation AI and Machine Learning

How to Start an AI Agent Evaluation Program (5-Task Scorecard)

Ship agents with a regression safety net: pick 5 real tasks, define pass/fail, run evals weekly in CI, and publish a scorecard that forces better decisions.

a computer screen with a blue background AI and Machine Learning

How to Do Agent Tool Call Failure Testing [2026 CI Harness]

Build a deterministic CI harness that breaks your agent’s tools on purpose: timeouts, 429s, partial writes, retries, and stuck loops. Then regress it with golden traces.

padlock on laptop with light trails Cybersecurity

LLM Supply Chain Security Checklist: Lock Down Agents [2026]

A CI-ready checklist to treat models, MCP servers, tool plugins, and prompt packs as real dependencies. Pin, sign, attest, sandbox, and monitor before your agent ships malware.

a computer screen with a blue background Cloud and DevOps

How to Back Up PostgreSQL With pgBackRest [S3 + Restore Test]

A restore-first pgBackRest setup for PostgreSQL: S3 repo config, retention math (weekly full + daily incrementals), PITR restore drills, and failure-injection tests.

Obsidian app markdown notes laptop screen — illustration for article on How to Upgrade Your LLM Developer Tools

How to Upgrade Your LLM Wiki in 2026: Sync, Search, Agent-Readable

The 2026 LLM wiki problem isn’t setup. It’s keeping it synced across devices, searchable at scale (BM25 + embeddings), and safe for agents to ingest without prompt injection.

GitHub Actions workflow run laptop screen — illustration for article on How to Do Prompt Injection Cybersecurity

How to Do Prompt Injection Regression Testing [2026 CI]

Your prompt-injection evals are probably overfit to cute synthetic prompts. Here’s a CI-ready regression suite that still catches indirect injection: seed corpora, adversarial transforms, canary secrets, and hard fail gates.

A security and privacy dashboard with its status Cybersecurity

AI Security Leader Playbook [2026]: 10 Controls That Ship

A practical AI security leader playbook you can implement this quarter: inventory, approval gates, agent threat modeling, OWASP LLM Top 10 controls, vendor review, and incident response.

Go code laptop screen developer — illustration for article on How to Upgrade to Go 1.27 Developer Tools

How to Upgrade to Go 1.27 in Production [Week-1 Checklist]

A pragmatic Go 1.27 upgrade playbook: toolchain pinning, CI matrix changes, perf validation (p99/allocs/GC), migration traps, and what to do with json/v2.

a laptop computer sitting on top of a wooden desk Cloud and DevOps

ChatGPT Down? 8 Fallback Patterns for API Outages [2026]

When ChatGPT goes down, your app shouldn’t. A production playbook for detection, retries with jitter, circuit breakers, bulkheads, throttling, and multi-provider failover.

turned on MacBook Air on desk Developer Tools

Mojo Language Open Source [2026]: What Python Devs Get Now

Mojo going Apache 2.0 changes the trust story. Here’s what’s actually open, how to install it, and where Mojo beats NumPy/Rust for real kernels in 2026.