Module 01 of 06 LIVE · Built for the operator who lost $4,800 in helmets

Every helmet
has a name on it.

Locker is the equipment, gear, and check-in/check-out engine of SidelineOS. Built after a single season where the founder watched $4,800 in helmets walk out the door of a 1,340-athlete program. Phone-based. Athlete-tied. Audit-trailed.

Live in production · 3,842 items tracked at NYF · $268K under management

https://app.sidelineos.com / locker / check-in

Today · Issuance Log

142 ITEMS OUT · 0 MISSING · ALL AUDITED
Athlete
Item
Tag
Status
JM
Jordan Mitchell · #22
10U STARS · QB
Helmet · Lg
H-0247
OUT
TS
Tyler Sanchez · #45
10U STARS · LB
Shoulder Pads · M
S-0118
OUT
EB
Ethan Barker · #88
10U STARS · TE
Jersey · Home
J-2284
RETURNED
DR
Devon Reed · #14
10U STARS · LB
Helmet · M
H-0188
OUT
MK
Marcus Kim · #7
10U STARS · WR
Pants · M
P-1147
OUT
$4,800
Lost in one season
NYF · BEFORE LOCKER
3,842
Items under management
NYF · LIVE TODAY
$268K
Equipment value tracked
FOOTBALL ASSETS
0
Items missing · audited
2025–26 SEASON
The Pain

Equipment is where
programs hemorrhage cash.

01 · MISSING INVENTORY
$4,800

Helmets walk away.

One NYF season. Eleven missing helmets. Three orphan shoulder pads. No way to know who had what. The replacement bill came out of program reserves — money that should have gone to scholarships.

02 · MANUAL RECONCILIATION
40 hrs

The spreadsheet doesn't scale.

Pre-season check-out: an equipment manager and a spreadsheet, by name, by helmet number, by hand. By week three, the spreadsheet is out of date. By week six, nobody trusts it. By week ten, the audit is impossible.

03 · NO PROVENANCE
∞ Qs

"Whose helmet was this?"

End-of-season returns: a pile of unmarked helmets. No record of who had #H-0247. No way to charge the family that didn't return it. The program eats the cost, every season, forever.

Features

What Locker does.

01 · Phone-Based Workflow

Check in. Check out.
From the table.

The equipment manager doesn't need a laptop, a printer, or a scanner. They need a phone. Locker is built around the table where gear actually changes hands — fast, mobile, accurate.

  • Issue gear in under 12 seconds per athlete
  • Scan a tag or type a number — either works
  • Look up athlete by name, team, or number
  • Works offline at the field — syncs when back on wifi
Quick issue · phone view
JM
Jordan Mitchell · #22
10U STARS · QB · CLEARED
Tag · scan or type
H-0247
✓ MATCHED Helmet · Lg · $385
02 · Athlete-Tied Gear

Every item
has a name on it.

Locker doesn't track items. It tracks the relationship between an item and an athlete. When a helmet leaves the table, the system knows whose helmet it is, who's responsible for returning it, and what it costs to replace.

  • One record per athlete shows all items they're holding
  • Item history follows the item across athletes and seasons
  • Replacement cost auto-attached to each item
  • Pulls athlete data live from Roster — no duplicate entry
Athlete profile · gear ledger
JM
Jordan Mitchell
#22 · 10U STARS · CLASS OF 2032
OUT Helmet · H-0247 · Lg $385
OUT Shoulder Pads · S-0388 · M $95
OUT Jersey · J-2244 · Home + Away $40
OUT Pants · P-1119 · M $45
RETURNED Practice Jersey · PJ-0917 $15
TOTAL GEAR VALUE OUT $565
03 · Audit Trail

Every transaction.
Forever.

When a parent disputes a charge in March, the equipment manager doesn't need to remember October. Locker has the timestamp, the equipment manager, and the athlete signature on every issue and return — all of it queryable, exportable, defensible.

  • Every check-in and check-out timestamped to the second
  • Equipment manager attribution on every transaction
  • Athlete or parent acknowledgment captured at issue
  • Export for end-of-season audit, board review, or legal
Item history · H-0247
ISSUED · J. MITCHELL · MGR M.E.08/22 · 9:14 AM
RETURNED · J. MITCHELL · MGR M.E.11/15 · 3:42 PM
CLEANED · QC PASS12/02 · 10:18 AM
ISSUED · T. SANCHEZ · MGR R.K.04/01 · 8:30 AM
ISSUED · J. MITCHELL · MGR M.E.08/24 · 9:01 AM
✓ 5 TRANSACTIONS · 2 SEASONS · ZERO DISPUTES
From the operator who built it

Built in the field.
Not the office.

GC
Founder Note
SidelineOS isn't a thesis. It's a tool I needed. I run a 1,340-athlete program across six divisions. Every module on this page started as a workflow I had to solve before Saturday. The fact that other operators need the same thing is the business — but the design pressure came from the field, not a focus group.
Geoff Cottrill Founder & CEO · NOVA Labs · President · Nolensville Youth Football
Operating Provenance

Numbers a competitor can't fake.

SidelineOS runs daily inside an active program. Here's what that program looks like.

1,340
Athletes
ACROSS 6 DIVISIONS · 6U–17U
Top 5
National NFL FLAG program
NYF · NATIONAL ACHIEVEMENT TIER
84
Playoff games · single cycle
MAY MADNESS 2026
$268K
Equipment under management
FOOTBALL PROGRAM ASSETS

Every helmet, accounted for.

Start free. Locker is live in production at NYF — 3,842 items tracked, $268K equipment value, zero items missing this season.