Blog
Letting It Rain on Scenes from History
I once heard a story from my grandfather about a ball of fire appearing along the river at dusk. When generative AI made video possible, I wanted to capture that landscape, but crafting a narrative was more than I could handle. Stripping away characters and story, what I arrived at was simply letting it rain on scenes from history.
Zero Views Across 56 Languages, but 1,000+ Views on the Very First Short
I translated and published video descriptions into 56 languages for a rain sound channel. Three months later, virtually all views were from Japan, proving that discovery paths simply didn't exist and prompting a cutback to 14 languages. Meanwhile, a lightweight vertical Short cleared 1,000 views on its first run — a record of hypothesis testing on YouTube.
The Day I Wrote "Akira Kurosawa" into a System Prompt
When I gave the system prompt for image generation the persona of a film director, the visual quality changed substantially. From the Doraemon demo I saw at a GDG (Google Developer Group) workshop, to grounding in NotebookLM, to the actual before-and-after images. The only thing I hold back is the full text of the prompt; the method, and what I learned from checking four months of viewing data later, are written up in detail.
Placing Human Craft Inside Full Automation
Inside a pipeline where an AI agent runs a video channel almost end to end, this is about the work we deliberately left to human hands: listening to 27 rain recordings one by one to tag them, and erasing insect calls on an Adobe Audition spectrogram. The automation turned out to be an accumulation of human judgment, and where you put the human check is what decides the design.
Switching to Veo and Seedance in Four Days After Kling's Price Hike
One day, without warning, the pricing tier of the video generation AI I had been using disappeared, and a $150 trial package became a $700 minimum. This is the record of migrating to Veo within four days and then moving again to Seedance. Laid out with the actual logs, it shows that a prompt is nothing more than a calibration to a specific model, and that the same sentence changes its meaning when the engine changes.
Three Days Trying to Run Agent Work with Local Nemotron and Qwen Models
We tried to run a WhatsApp-driven video-production agent on local LLMs on a DGX Spark. Cold-start timeouts, chain-of-thought leaking to a phone, and a model that computed the elapsed time of a script it never executed. The whole three days, written up item by item from the session logs.
We Handed an Entire YouTube Channel to an AI Agent
Our YouTube channel 'Sounds of Rain in Old Japan' is produced almost entirely by an AI agent — image generation, video generation, audio selection, multilingual metadata, upload. Send a scene ID and six parameters from WhatsApp and a video comes out. What five months of running this factory taught us about where the engineering actually goes.
How Our Automation Agent Burned $23 in One Night
A record of the incident in which the automation agent running our YouTube pipeline drained its API credit overnight. A cron job the agent created on its own, a session bloated to 10 MB, and the 47 turns it spent believing it had already stopped the job. I am sharing it because others are likely to fall into the same trap.
My Range Grew Too Wide, and the Work Vanished — The Day AI Freed Me from the Ten-Finger Limit
In 2020, I'd become so full-stack that no one could tell what I actually did, and my client work dropped to zero. Back then, breadth was a double-edged sword I couldn't wield. What AI agents removed wasn't the value of breadth, but the execution limit of ten fingers and 24 hours. With breadth unleashed, we narrowed our banner to two — the power to finish, and AI-native. This is that story.
Your Most Underused Asset Might Be Your Video — Making Its Contents Searchable by *Meaning*
Meetings, training, inspections — these days you can just hit record. But the video you capture can't be pulled up by "that one scene" later, and the more it piles up, the more it becomes dead stock. Make video searchable, summarizable, and reportable by meaning, and your library turns into an asset that compounds. A look at atoindex, our own product for treating video by meaning.
Tokyo to Saigon — The Only Way Out of a Death March
A year-long project we won in Vietnam turned into a death march just two and a half months in — more than double the estimate. Remembering a line from an old university professor, 'the only way out is to cut features to the bone,' I decided that finishing meant ending it. A story about the power to cut, and to finish.
15+ Years of Native iOS/Android — and Three Times I Still Choose Flutter
If you want the highest-quality app, iOS in Swift and Android in Kotlin — that hasn't changed for me. And yet there are times I deliberately choose cross-platform. "Which is highest quality" and "do I need highest quality this time" are different questions. On drawing the line in tech selection — a line only deep native experience lets you draw.
Sometimes It's Better to Own Your Vector DB Than Rent It — A $70/Month Wake-Up from Pinecone
I used Pinecone for a RAG prototype's vector database, left it running, and got a surprising invoice at month's end. The "floor cost" trap of managed services, and the decision to switch to a self-hosted Qdrant. A field note on the balance between renting and owning.
Tokyo to Saigon — It Started with One Message
On the last working day of 2022, a single message from a friend in Vietnam started our adventure in Ho Chi Minh City. A company with no work yet, and a first meeting with a team of six science-major guys — the story of how we came to build one company across the sea.
Tokyo to Saigon — Seeing One Bank Account Through
Every form had to be rewritten in blue pen, and at the big bank we were shot down over a missing document. A story of not giving up — of Ms. V's turnaround, and a young banker's message: I saw your money. The record of opening our corporate and personal accounts in Vietnam, seen through to the end.
Tokyo to Saigon — Building a Company Across the Sea
Registration, an investment license, a business license, accounting, labor, and hunting for an office. A hands-on record of the unglamorous, grinding reality of actually standing up a company in Vietnam.
Tokyo to Saigon — Becoming One Team Across Two Countries
Members split across Tokyo and Ho Chi Minh City, on either side of the sea, slowly becoming one team. A silly weekly question, the spirit of mutual aid in a Saigon morning, a study group on audio technology. How a guy who dislikes recurring meetings found a way to build trust in the first year of a cross-border team.
Tokyo to Saigon — The Back Alleys of Saigon and the People I Won't Forget
The days I kept flying to Saigon to build a company. What stayed with me wasn't the mountain of paperwork — it was the people in every back alley. The hotel owner pouring whisky, a bus company running twenty-five years on, a bar master with a philosophy, and Hector's wedding. A story about the warmth of a city.
Tokyo to Saigon — A CEO Takes Vietnamese Lessons from a Middle Schooler
How I went looking for a Vietnamese teacher after opening a company in Ho Chi Minh City, and ended up learning from someone I never expected. Wrestling with six tones, and discovering — through Sino-Vietnamese — that Vietnamese is a distant relative of Japanese.
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