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I design AI-powered product with creativity and systematic thinking.
B2B/B2C SaaS for creative & production workflow.
Currently @ReelShort.
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ReelShort Addendum Studio — Payroll & Legal Compliance System for ReelShort
ReelShort Addendum Studio
Designed and built an automated payroll documentation tool for ReelShort, simplifying contract preparation, payment paperwork, and compliance workflows for production teams.
ROLE
PRODUCT DESIGNER
DESIGN ENGINEER
PRODUCT DESIGNER
DESIGN ENGINEER
SCOPE
Research & Rules Modeling
UIUX Design
Front-end Build
Research & Rules Modeling
UIUX Design
Front-end Build
Part of the content has been anonymized. All names, amounts and production details shown are fictional or generalized. Real contractor, payroll and legal data is confidential.
｜27 contractors ｜7 departments ｜8 paperwork steps per person ｜~139 OT hours reconciled ｜21 addenda per production ｜3 location rule sets ｜7 fee categories ｜
Overview& Context
The addendum is one step in an eight-step pipeline — and the only one that involves maths.
Every contractor on a ReelShort shoot moves through the same paperwork pipeline, tracked row by row in a crew batch sheet. Seven of the steps are "send and collect". The addendum is different: it turns negotiated terms and the production's time record into a pay calculation the producer signs.
On the reference production — a 10-day Texas shoot with 12-hour contracted days — 27 contractors across 7 departments went through this pipeline, and 21 of them needed an addendum. Each one was rebuilt by hand in Word and a personal spreadsheet.
The reference production is an anonymized composite based on typical shoots. Figures are illustrative.
01Welcome letter
02Agreement
03W-9
04Invoice
05 · this projectAddendum
06Folder
07Payment
08Finance
The Problem
The hard part wasn't the document. It was everything feeding into it.
Each addendum looks like a one-page form. Underneath sit three messy inputs — a free-text deal memo, a timecard export and a location rule — that only someone who knew the rules could reconcile. I started from the real crew batch sheet and traced every number on a signed addendum back to its source.
| Title / Role | Contractor | Payment details (free text) | Day rate | Hrs | Days | Flat fee | OT hrs | OT $ | Total | W-9 | Invoice | Addendum |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PRODUCTION DEPARTMENT | ||||||||||||
| Director | A. Rivera | Flat prep / shoot | $8,000.00 | $8,000.00 | Done | Done | N/A | |||||
| Line Producer | N. Kim | $420/shoot day + $1000 flat prep/wrap — 10 days | $420.00 | 12 | 10 | $1,000.00 | 16.50 | $742.50 | $5,942.50 | Done | Done | Done |
| 1st AD | G. Okafor | $1000 flat prep, $360 / 12 hour shoot day … | $360.00 | 12 | 10 | $1,000.00 | 7.00 | $270.00 | $4,870.00 | Done | Done | Done |
| GRIP AND ELECTRIC DEPT | ||||||||||||
| Gaffer | M. Alvarez | $280/12 hour day — 2 days | $280.00 | 12 | 2 | 0.40 | $12.00 | $572.00 | Sent | Sent | Done | |
| ART DEPT | ||||||||||||
| Art Director | Studio vendor LLC | Flat fee for whole art direction service | $3,900.00 | Done | Done | N/A | ||||||
Deals arrive as sentences
"$1000 flat prep, $350 / 12 hour shoot day, 10 days" had to be re-read and split into rate, hours, days and fees before any maths could start.
"$1000 flat prep, $350 / 12 hour shoot day, 10 days" had to be re-read and split into rate, hours, days and fees before any maths could start.
Overtime law differs by state
California pays 1.5× after 8 hours and 2× after 12; Texas and most other locations stop at 1.5×.
California pays 1.5× after 8 hours and 2× after 12; Texas and most other locations stop at 1.5×.
Fees compound on each other
Hourly rate is backed out of a weighted day; OT and meal penalties depend on it; agency fees apply to flat + base + OT, never to per-diems.
Hourly rate is backed out of a weighted day; OT and meal penalties depend on it; agency fees apply to flat + base + OT, never to per-diems.
Batch work, one-off tools
Dozens of contractors paid in weekly waves — but addenda were built one at a time, with signatures pasted in after the fact.
Dozens of contractors paid in weekly waves — but addenda were built one at a time, with signatures pasted in after the fact.
From a sentence to structured fields
"$1000 flat prep/wrap, $420 / shoot day, 12 hour day, 10 day shoot"
→
Flat fee · Prep & wrap$1,000.00
Principal day rate$420.00
Contracted hours12 hrs/day
Working days10
A 14-hour day is three pay rates in California — and two in Texas.
Contracted hours are folded into weighted bands to back out a true hourly rate; every OT hour from the production record is then re-priced per working day.
California
1× · hrs 1–81.5× · 8–122× · 12+
Texas / Other1× · hrs 1–81.5× · over 8
0h4h8h12h14h
12-hr day, Texas8 + 4 × 1.5 = 14 weighted hrs
Hourly rate$420 ÷ 14 = $30.00
Recorded OT (1.65 hrs/day)1.65 × 1.5 × $30 × 10
OT fee on the addendum= $742.50
Design Principles
Model the rules once. Let the interface stay simple.
Derive, never type
Hourly rate, OT, meal penalty, agency fee and total are outputs. Nobody hand-edits a number the engine owns.
Hourly rate, OT, meal penalty, agency fee and total are outputs. Nobody hand-edits a number the engine owns.
The batch is the unit
Accountants think in productions and pay waves, so the home view is a project with progress and exposure.
Accountants think in productions and pay waves, so the home view is a project with progress and exposure.
Enforce, don't explain
Order, validation and approval locks live in the product, replacing tribal knowledge.
Order, validation and approval locks live in the product, replacing tribal knowledge.
BEFORE
① Read the free-text deal memo
② Copy last project's Word template
③ Rebuild formulas in a spreadsheet
④ Look up the state's OT tier
⑤ Type figures, paste a signature, export
⑥ Repeat for ~21 contractors
① Read the free-text deal memo
② Copy last project's Word template
③ Rebuild formulas in a spreadsheet
④ Look up the state's OT tier
⑤ Type figures, paste a signature, export
⑥ Repeat for ~21 contractors
AFTER · ADDENDUM STUDIO
① Pick the project — location rules apply
② Import the crew batch CSV
③ Fix only records flagged "Needs fix"
④ Finalize approval — record locks
⑤ Batch-export every addendum as PDF
① Pick the project — location rules apply
② Import the crew batch CSV
③ Fix only records flagged "Needs fix"
④ Finalize approval — record locks
⑤ Batch-export every addendum as PDF
01 Rules Engine
A rules engine, not a template.
Choosing a location sets the overtime bands for every record on the project; changing a day rate re-derives hourly rate, OT, meal penalty and agency fee instantly. Each fee category is an optional, collapsible section with a live subtotal — and blank categories disappear from the final document.
Scan, then drill in — each fee category shows its own subtotal while collapsed.
Derived, never typed — the hourly rate is computed and locked.
Texas project — OT at 1.5×, band rule printed under the hourly rate.
California unit — same template, 1× / 1.5× / 2× bands applied automatically.
02 Built for Batches
The production, not the document, is the unit of work.
The workspace opens on crew count, finalized ratio, records needing attention and the running project total. The queue carries each contractor's amount and status, and filters straight to the records that block a pay wave. CSV import uses alias lists and fuzzy header matching, so the crew sheet production already keeps becomes the input.
Project summary strip — progress and total exposure always visible.
Many units, one tool
The queue is the to-do list
One click to blockers
03 Guardrails
Guardrails over manuals.
Crew editing stays locked until the project is defined. Validation runs on every keystroke and marks the exact field that's wrong. Export is blocked while any record fails. Once a producer finalizes, approver, date and signature lock — payment lines stay editable, but approval can't drift silently.
Errors where they live — flagged on the field itself.
Signed means signed — approvals lock until Edit.
04 WYSIWYG
What you see is what gets signed.
The right-hand pane is the actual print layout, updating live. Reviewers never reconcile a form against a separate output — the document is the interface, and switching to a California unit re-renders every preview with its own overtime law.
Impact
From a per-document chore to a per-production workflow.
~85%*less time to prepare a production's addenda batch
0manual formulas left in the addendum step
4 → 1tools consolidated: deal memo, template, sheet, PDF/signing
100%of exported records pass validation
Fewer payment re-issues
Location-aware OT and a visible formula target the most common re-issue: the wrong tier copied from another project.
Location-aware OT and a visible formula target the most common re-issue: the wrong tier copied from another project.
Approval you can audit
Finalized records lock signature and date — a clear line between draft and approved before each pay wave.
Finalized records lock signature and date — a clear line between draft and approved before each pay wave.
Onboarding in minutes
A new coordinator can produce a correct addendum without learning the rules first.
A new coordinator can produce a correct addendum without learning the rules first.
What's next
Ingest OT hours straight from the production timecard export · write addendum status back to the crew batch sheet · replace uploaded signature images with a producer e-signature and audit trail.
* Estimated from walkthroughs of the previous manual process. Reference counts come from one ReelShort crew batch; product screens use fictional demo data and no personal or payment data is shown.
About this case study
Addendum Studio is an internal ReelShort tool that handles payroll and contract data. All data in this case study is fictional, and some details have been generalized. Part of the content has been anonymized.