Nhi Diary
Private beta · AI-assisted · in daily use by our own family

An AI-assisted journal of a child growing up.

Nhi Diary keeps a child's photos, growth and milestones in one private place, and uses AI for the sorting parents never have time for. Face recognition already finds your child among hundreds of kindergarten photos every week. Generative recaps and captions come next.

See the AI pipeline Get in touch
Nhi Diary home screen with the latest measurement, recent milestones, the latest diary note and recent photos

Screenshots use a demo child and illustrations, never real family photos. The app is in Vietnamese.

Live today

AI that sorts the school photos for you

Kindergartens post hundreds of class photos a week, and a parent's own child is in a small share of them. Every night Nhi Diary works through the new ones so parents only see their child.

  1. 1

    Collect

    Pulls new photos, daily notes and health-check measurements from the kindergarten's parent app.

  2. 2

    Recognise

    A face recognition model (InsightFace) compares every face with a reference set of your child only, on our own server.

  3. 3

    Decide

    Confident matches import automatically, uncertain ones wait on a review page for a parent, and the rest are skipped.

  4. 4

    Journal

    Matched photos land in the diary by day, next to the class notes and the growth chart.

1,029parent-labelled decisions used to tune the match thresholds
~3 sper photo on a mini PC CPU, no GPU and no cloud call
0embeddings of other children stored: they are discarded after each photo

Everything else a family needs

Built for parents and used on the phone first: open it from the home screen like an app, add a photo or a note in a few seconds.

Growth chart with the child's height plotted against WHO percentile curves
Growth against WHO standards
School photo library grouped by day
School photos, grouped by day
Milestone timeline with photos
Milestones with their photos

Photos and short videos

Upload straight from an iPhone. Originals are kept, and videos are compressed so they play smoothly on mobile data.

Growth charts

Height and weight plotted against WHO child growth standards, entered by hand or taken from the school's health checks.

Milestones and diary

First words, first steps, everyday moments, each one linked to the photos that go with it.

Printable album

Export any period as a PDF photo album to print or send to grandparents.

Family-only access

Every page sits behind sign-in limited to invited family emails, and only parents can add, edit or delete.

Encrypted backups

Nightly backups, with an off-site copy encrypted under keys the family holds.

In development

Generative AI with Claude

None of these are live yet. Claude is our primary model for them; each feature will be opt-in for parents and will receive only the data it needs.

  1. Q4 2026

    Photo captions and tags

    A nightly job sends new home and school photos to Claude vision through the Message Batches API and stores suggested captions and tags, so finding "the beach trip" takes one search. First prototype runs on our own archive of about 1,300 photos.

  2. Next

    Monthly and yearly recaps

    Claude reads the month's diary notes, class notes, measurements and captions and writes a short story of what changed.

  3. Next

    Growth Q&A

    Our code computes the child's WHO percentiles; Claude explains them through tool use, so every number comes from the app's own data. Not medical advice.

  4. Later

    Keepsake book

    Claude writes the chapter introductions for the printable album, one for each stage of the year.

Built with

  • Claude APIvision captions, recaps and tool use (in development)
  • InsightFace · ONNX Runtimeface recognition on CPU
  • Pythonnightly collect, score and import pipeline
  • Next.js · SQLitethe journal app
  • CloudflareTunnel, Access sign-in, Workers, R2 backups
  • Claude Codehow the app is built

Who's building it

Jason Truong

Jason Truong (Trương Hoàng) · Founder

Ho Chi Minh City, Vietnam

I'm a parent and a software project manager. I wanted one private place for everything about our daughter's early years, instead of photos scattered across chat groups and a school app, so I built Nhi Diary for our family first, with Claude Code as my pair programmer.

Next I want to open it to families everywhere, not only in Vietnam. That means an English interface, sign-up and accounts for many families, and the generative features above: a lot of building still ahead.

jason@nhidiary.fyiLinkedIn

Founded 2026 · Ho Chi Minh City · Bootstrapped

Principles

  • A child's photos and records belong to the family. No ads, no public profiles, no selling data.
  • Face recognition runs on our own server and stores only your own child's reference set.
  • Generative AI features are opt-in and receive only the data the feature needs.
  • Off-site backups are encrypted with keys the family holds.

Read the privacy notice