Jejak Penanaman

The problem

Otorita IKN runs tree-planting events in Nusantara, the new capital, for its own employees and for the public. Attendance used to live on paper forms and spreadsheets. Nobody could tell whether a participant was actually on site. There was no central record of who came to which event, no log of which species went into the ground, and no photos.

Three kinds of people had to fit into one system. Employees sign in with their government account. Members of the public register with an email address. At open events, some people simply walk up with no account at all. Admins needed to create events, place them on a map, track registrations and export attendance reports.

What I built

Check-in needs a selfie taken at the site

To check in, a participant takes a selfie and shares their location. It has to fall inside a radius the admin sets for each event, from 50 to 5,000 metres around a pin on the map. The phone checks the distance first and tells the participant how far away they are. The server checks it again, so nobody can fake a check-in by calling the API directly. Photos are compressed on the phone to stay under 1 MB.

Every photo carries its own proof

Before upload, the phone stamps each selfie and plant photo with the date, the local time in WITA and GPS coordinates to seven decimal places. The same location is also written into the photo's metadata. The server does no image processing at all. The proof travels with the file, so a photo downloaded later still shows where and when it was taken.

One attendance record, three ways in

Employees sign in through the government's single sign-on. Their names and work units arrive in inconsistent formats, so I clean them up on login. Public participants register by email and receive a generated password. At open events, a walk-up participant can check in without registering. The system creates a lightweight guest account on the spot, and permissions for everyone else stay the same.

I added plant records halfway through

Species tracking wasn't in the original spec. I added it mid-project to support IKN's reforestation records, without breaking the existing data. Each check-in can list several species, with a count, the sapling's age in months and photos. A personal "Jejak Hijau" page shows a participant everything they have planted across every event.

Public events get tickets and per-institution quotas

Public events issue a QR ticket per registration. Admins scan tickets at the gate with a phone camera, and each result plays a sound. Quotas started as one number per event. When government institutions asked for their own allocations, I made per-institution quotas and t-shirt sizes an option on each event. Simpler events keep a single quota. Participants can also take a selfie in a branded IKN frame and download it to share.

Admins can fix what the field breaks

Outdoor events lose signal. Admins can record attendance on a participant's behalf, set the time it happened, and add plant photos to an existing record later. A superadmin role manages the admins and can promote a public user to employee status. That locks the user's unit details, so a later sign-in can't overwrite the correction.

Result

Jejak Penanaman is in production and has been used at IKN tree-planting events since mid-2026. I built it between April and July 2026, and production was running by June. One codebase handles two kinds of event. Internal events are sign-in only, with no registration. Public events have registration, quotas, QR tickets and walk-up guests. Admin dashboards break attendance down by directorate and deputy office, with a ranked table for internal reporting. The app has 28 screens across the participant and admin sides.