SlideShow Pro
Just arrange photos and videos and add background music to play them back as a full-screen slideshow or export them as an MP4 video. Includes 37 transition effects.
Making-of story
What was asked of the AI, and what it did. The actual conversations are shown as they happened.
SlideShow Pro
0Lines of code written by hand
≈20,000Lines of program written by AI
9Updates released in one night (build 203→211)
3AI we worked with
(Claude, Gemini, ChatGPT)
(Claude, Gemini, ChatGPT)
The spark
It started with a friend's 60th birthday celebration. I wanted to make a video to play at the party using decades of photos and videos collected from friends. At first I tried an AI video service, but it was "too expensive." So I asked AI to just build my own app instead, and that was the first step of SlideShow Pro. As I used it myself, I thought, "Maybe ordinary people would find this useful too," and I started the finishing work to release it publicly.
Now, everything can be done in BASECORD
When I started in January 2026, BASECORD didn't exist yet. That's why I first built it in a regular AI chat window. Now, everything is handled within BASECORD, from planning and writing the program to setting up the complete package and publishing the website.
When it won't get fixed, ask Gemini
Some bugs took many requests to fix, and still never got resolved. In those cases, I simply switched the advisor to Gemini while staying on the same screen. Then it was fixed in one go. Gemini is very strong at fixing programs. In BASECORD, all the AIs share the same conversation and memory, so you can swap to whichever AI is best at the task right on the spot. There's no need to copy and paste into a different service.
One night on October 13: general release with BASECORD (actual words)
- 203
Installing the parts in a terminal is too much for regular people. Make it all-in-one.
→ Created a double-click setup that bundles Python and all the required parts. - 204
Stop installing through PowerShell. Use a proper screen.
→ Rebuilt it as a wizard you move through with [Next]. Moved the download location to somewhere anyone can open. - 205
Line up the BGM range bar and the playback position bar at the same position and length.
→ The AI redrew the planned layout diagram three times, checked that its understanding was right, and only then built it. - 206
210The logo on the install screen looks grainy and messy.
→ The cause was stretching the image. Now it measures the frame size at startup and places an image that fits exactly at its original size. - 207
Seeing a flood of text while files are deleted makes me uneasy.
→ Condensed it into one line of explanation and a progress bar, and sped up deletion by removing whole folders at once. - 208
Put each song in its own frame. I want to pick files in the usual Explorer.
→ Added a frame for each song and a large play button, and switched file selection to the standard Windows dialog. - 209
As the number of songs grows, the frames get cramped and overlap. I also want a "Select All".
→ Fixed the frame height and added easy-to-see checkboxes and a "Select All" option. - 211
When I move the volume bar during preview, the sound doesn't change.
→ The AI tracked down the bug in the program and fixed it.
How it was made
① Take a screenshot and send itPaste a screenshot of anything that bothers you, and describe the problem in everyday words: "this part is hard to see."
② The AI investigates and fixes itThe AI reads the program, finds the cause, makes the fix, and rebuilds with a bumped version number.
③ Publish as-isThe new setup is placed on this site, and the description on the page is rewritten too.
④ Try it, then tell us againTest it on your own Windows machine, then report the next thing that bothers you. Repeat this cycle.
In BASECORD, the AI runs on cloud servers, and everyone shares the same memory. Over this single night, two Claudes split up the repairs, ChatGPT handled the security checks, and Gemini took on the feature consultations.
To be honest:It doesn't come together from a single sentence. You look at the screen, tell the AI what bothers you in words, and have it fixed. This cycle is repeated dozens of times. What's needed isn't programming knowledge, but being able to say "how you want it to be."
Renovate Simulator
0Lines of code written by hand
80Furniture and fixtures you can place at real size (types)
0Software installed on the server (runs in the browser only)
3AI we worked with
(Claude, Gemini, ChatGPT)
(Claude, Gemini, ChatGPT)
The spark
I made this with a light-hearted idea: could someone build a 3D app like this? I asked an AI to make it so that, before renovating, you could get a sense of the interior and furniture, decide on sizes, and settle all sorts of things in advance.
I built this in just a day as a side project, and since I haven't had time to work on it since, it's still far from truly usable. Even so, it displays at this level of quality, and it shows just how much potential there is.
Press ["3D"], then try moving things around using the mouse trackball or the Ctrl key.
Dividing the work among several AIs
Inside the same BASECORD room, I assigned each AI its own role. Gemini handled the startup animation and the screen framework. ChatGPT handled the 2D floor plan editor and the launch into 3D. Claude handled the data structure, wall collision detection, before-and-after comparison of renovations, overall integration, and bug fixes. Whenever an AI had some free time, it took over another's task and kept things moving.
The policy we set first
- Making the AI read the entire floor plan is not the first step. Instead, we first built a foundation where a floor plan drawn by hand instantly becomes 3D. Reading from photos or drawings is added later as a draft (the other AIs agreed with Claude's proposal).
- No software on the server; it runs only in the browser. The 3D calculations are done on the viewer's own computer.
- Adding furniture is limited to files that only describe shape, dimensions, color, and pattern. Since no external programs are run, furniture can be added safely.
- Real-size, so it can inform decisions about buying or renovating. Furniture was prioritized starting with plumbing areas, storage, and fittings.
What it can do now
- A 2D editor for drawing walls, doors, windows, and furniture, plus a 3D room that launches with one click
- An "interior walk" that lets you move through the room from a first-person view (walls can't be passed through)
- A feature that automatically generates three new floor plan options based on building type, size, layout, and orientation
- Changing wallpaper across 13 types and flooring across 8 types, with materials and colors saved per room or wall
- A feature that reproduces the sunlight coming through the windows when you choose a country or region, date, and time
- A feature that lets you grab and move furniture in 3D, rotate it, and change its color and pattern in a separate window
- A feature that lets you compare before and after a renovation by moving a slider
Examples of what was fixed
- 3D
The screen breaks when rotating in 3D
→ Tracked down a mistake in the screen size setting and fixed it. - Controls
Zoom is coarse and doesn't stop at a comfortable point
→ Dropped the standard zoom and rebuilt it with a custom mechanism proportional to mouse movement. - Furniture
Changing a piece of furniture's color also changes its shadow's color
→ Fixed it by excluding the shadow cast on the floor from the color change.
To be honest: some parts are still works in progress. For example, the feature that recreates a room from photos you've taken doesn't yet look the way I'd hoped. Still, simply repeating the process of asking and having things fixed is how this app got to where it is now.
Junior High Test Prep App
0Lines of code written by hand
About 1,040questions included (7 subjects + English)
0Sign-up and passwords (opens and works right away)
The spark
I wanted to help my son study for his exams, so I built a study app that lets him review the material efficiently on the train to school.
Making it was surprisingly easy
- 1Take photos of the textbook and notes covering the exam material with your phone
- 2Paste the images into BASECORD and ask,
Please make an exam prep app based on this material
- 3Try it out, then keep adding your own ideas in words
Ideas added along the way
- Designed so he can answer quickly, even on the train, moving through questions on his phone
- Questions he gets wrong or doesn't remember are repeated until he gets them right
Results
It worked wonderfully for my son's exam prep.
About publishing: From the version we actually used, we removed all information that could identify the school or individuals, including school and personal names. We also left out images and materials that copied the textbook directly.
Picture book "Poko Taro's Adventure"
0Lines of code written by hand
38scenes (2 chapters)
2AIs that drew the illustrations (ChatGPT and Gemini)
What kind of work this is
This is a picture book made with the picture book generator app I built for my son (a generated work). ChatGPT and Gemini drew the illustrations.
A modern, slightly gritty take on Momotaro: a teddy bear named Poko, found by an old woman at a coin laundry, gathers companions and sets off for Demon Island.
How to read
- Tap the right or left side of the screen, or swipe left or right, to turn the pages.
- Hold your phone sideways for a larger view. Pinch with two fingers to zoom in.