Sebastian PE — Go, AI & Engineering

Agent Memory: From Isolated Context to Collaborative Memory

Mon, 29 Jun 2026 00:00:00 +0000

A deep dive into LLM agent memory architecture based on the MemRec paper (ACL 2026): collaborative memory, decoupling memory management from reasoning, Information Bottleneck. Comparison of the TOP-3 production tools — Mem0, Letta (MemGPT), and Zep — across nine axes. Highlighting the gap: research outpaces tooling.

Go Internals: sync.Mutex and sync/atomic — From Data Race to Starvation Mode

Thu, 18 Jun 2026 00:00:00 +0000

Mutex and atomic are not two independent tools — they are one stack of abstractions. I dig through the stack from data race to starvation mode: why x++ is three ARM64 instructions, how CAS became a universal primitive (Herlihy 1991), why Mutex is built on top of atomic CAS, and how Russ Cox’s barging-vs-handoff debate (issue #13086) gave Go its 1ms starvation threshold. With public benchmarks, the bit layout of Mutex state, and a cheatsheet for when to reach for which.

AI Agent Design Patterns. Part 6: Agent Memory in Practice

Thu, 11 Jun 2026 00:00:00 +0000

Deep dive into agent memory mechanics: five memory files, four context assembly strategies, TOOLS.md as a dual-source responsibility, and Dreaming — background consolidation from Anthropic (Auto Dream, Dreams API, KAIROS) and OpenAI (Dreaming V3, 82.8% factual recall). Engineering decisions behind a production platform.

AI Agent Design Patterns. Part 4: Multi-Agent Patterns

Mon, 08 Jun 2026 00:00:00 +0000

Five multi-agent orchestration architectures — Supervisor, Swarm, Debate, Assembly Line, Hierarchical — with Mermaid diagrams, code examples in Eino (Go), and an honest look at limitations. When one agent isn’t enough, and when you’re better off staying solo.

AI Agent Design Patterns. Part 5: Agent Memory Management

Mon, 08 Jun 2026 00:00:00 +0000

Context window ≠ memory. I break down agent amnesia, the academic taxonomy (Du et al., 2026), five approaches to memory — from OpenClaw’s file-based brain to mem0’s managed layer — and how our team solves this in practice.

AI Agent Design Patterns. Part 2: Plan-and-Execute Pattern

Sun, 07 Jun 2026 00:00:00 +0000

Plan-and-Execute separates strategic planning from tactical execution. I break down the Planner+Executor+Reviser architecture, ReWOO and LLMCompiler variants with numbers from original papers, prompt injection defense via control-flow integrity, and a minimal working Go example with Eino.

AI Agent Design Patterns. Part 3: Reflexion Pattern

Sun, 07 Jun 2026 00:00:00 +0000

Reflexion is a pattern where an agent learns from its own mistakes through verbal reinforcement and episodic memory. I trace the evolution of self-critique from Constitutional AI to Reflexion, honestly show its limitations (doesn’t work without an external verifier), and implement a working example in Go using Eino compose.Graph with an Actor → Evaluator → Reflector → retry loop.

AI Agent Design Patterns. Part 1: ReAct Pattern

Sat, 06 Jun 2026 00:00:00 +0000

ReAct (Reasoning + Acting) — the foundational AI agent design pattern that interleaves reasoning and action in a single loop. I break down the architecture, numbers from Yao et al. 2022, framework landscape, and a minimal working Go example via Eino.

Getting Started with Hugo + PaperMod

Fri, 05 Jun 2026 00:00:00 +0000

How this blog was born — Hugo, PaperMod theme, Mermaid diagrams, KaTeX math, custom dark styling, and fully automated CI/CD via GitHub Actions.

About

Mon, 01 Jan 0001 00:00:00 +0000

Hi, I’m Sebastian PE — a full-stack software engineer with 15+ years of experience building web products, backend systems, and developer tools.

What I Do

I work across the entire product lifecycle — from architecture and prototyping to launch and operation. My current focus:

Go — high-performance backend services, concurrent systems, microservices
AI & LLM Agents — prompt engineering, RAG pipelines, agentic orchestration
PHP & JavaScript — full-stack web development, API design
DevOps — CI/CD, observability, infrastructure as code

I’ve built e-commerce platforms, web portals, CRM and ERP systems, and business tools. I also have extensive experience as a team lead and head of development, managing engineering teams and designing software architecture.

Projects

Mon, 01 Jan 0001 00:00:00 +0000

Open Source

Project	Description
blog	This blog — Hugo + PaperMod, auto-deployed via GitHub Actions

Teaching

Udemy courses on software engineering — profile