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Notes on building AI that actually works.

RAG and semantic search, LLM integrations, agent pipelines and the backends underneath — practical posts written while shipping.

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Work with meTaking projects

I build what I write about — RAG and semantic search, AI integrations and agent pipelines, on backends in Go and Python.

Free · no commitment · I read every request myself

Latest · AI integrationsOct 16, 2026 · 6 min read

Claude Code subagents get a 5-minute cache even on a subscription: when to set it to 1h, and how to check

On a subscription your main Claude Code conversation gets a one-hour prompt cache, but subagents, workflows and compaction stay at five minutes. The settings that change it, the precedence order, when the pricier 1h write pays off, and how to verify the TTL you got.

#claude-code#prompt-caching#subagents#llm-costsRead the post

AI integrations

Oct 13, 2026 · 5 min readPostgres feels slow on your VPS? Benchmark the disk before you touch postgresql.confClickHouse measured the same Postgres box at 16,030 TPS on local NVMe and 1,734 TPS on a baseline gp3 volume, with most of the gap spent waiting on storage. A 15-minute fio and pg_test_fsync check tells you which side of that table your VPS is on.#postgres#self-hosting#performance#databases

Infrastructure

Oct 13, 2026 · 4 min readA quoted ~ in your PATH runs whatever sits in ./~/: a one-line check for dotfiles, servers and CI imagesexport PATH="$PATH:~/.local/bin" never expands the tilde. Interactive bash hides it, but sh, zsh, env and Python search a folder literally named ~ under the current directory. The check, the fix, and where to grep.#linux#shell#security#devops

Infrastructure

Oct 11, 2026 · 6 min readDocker publishes ports straight past UFW: hardening a fresh VPS without the firewall rule that does nothingufw deny 8080 does not stop a Docker container published on 8080. Docker's own docs explain why. A 15-minute fresh-VPS walkthrough: key-only SSH, ufw, then the two fixes that actually close a container port, and a scan from outside to prove it.#docker#security#vps#firewall

Infrastructure

Oct 10, 2026 · 6 min readDeno Deploy shuts down in six months: moving a small app to Cloudflare Workers, self-hosted Deno in Docker, or NodeDeno is joining Cloudflare: Deploy has six months left and the runtime gets a year of fixes. Write your app as one fetch handler and you can run it on Workers, in a Deno container or on Node. Code for all three, plus what does not carry over.#deno#cloudflare-workers#migration#docker

AI integrations

Oct 9, 2026 · 7 min readThe Durable Object alarm that cost $10,000: guarding setAlarm() loops with backoff, idempotency and a kill switchDurable Object alarms are at-least-once, retried, and usually rescheduled from inside the handler, which makes a billing loop easy to write. Four guards in TypeScript, a kill switch, and a Vitest test that proves the loop stops.#cloudflare#durable-objects#typescript#cost-control

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// what I write about — and build

Three topics. Also three things I build for clients.

Every topic has posts to read and a free quote if you want it built for your data and systems.

RAG & semantic search

Search and assistants that answer from your own documents — with sources, and a handoff when they’re not sure.

Embeddings & vector search
Hybrid keyword + meaning search
Assistants with citations

AI integrations

LLMs wired into the systems you already run — tickets, CRM, catalog, inbox — with costs and quality you can see.

Summaries, drafts, classification
Translations and content generation
APIs, webhooks, your own model

Agent pipelines

Multi-step agents as inspectable workflows — they plan, act and check, and a person approves anything that matters.

Workflows you can open and trace
Human approval steps
Event-driven, retry-safe backends

New posts by RSSOne entry per post, no tracking — works with any feed reader.Subscribe to the feed

// about

One engineer. I write about what I build.

Software engineer working on RAG, AI integrations and agent pipelines on Go and Python backends. Author of the Redelay framework and the FlowDSL workflow engine. Remote, EU time zones.

GoPythonRAGembeddingsLLM APIsagentsKafka / NATSMongoDB

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// free quote

Read something you need? I’ll quote it for free.

RAG, AI integrations, agents or the backend underneath — tell me what you have and what should change. I read every request myself.

Free · no commitment

Tell me what you have. I’ll tell you what it takes.

1Describe the projectA few sentences is enough — about two minutes.

2I review itI read it myself and may ask a follow-up question.

3You get a free quoteScope, approach and estimate — yours to keep, no strings.