Paccess

Chapter 1: What is an "Access Compatibility Layer"?

Digitally recreating a 20-year-old Stradivarius

Microsoft Access. The king of business systems since the 1990s.

But times have changed. Cloud, multi-platform, modern development environments — requirements that Access can't handle are increasing.

Normally, you'd say "Let's abandon Access and migrate to a new system."

But that means throwing away 20 years of assets.

• ▶ Accumulated business logic
• ▶ User "familiarity" — the ultimate UX
• ▶ Muscle memory: "Press this button, get this result"

Paccess chose a third path.

Transplanting the "soul" of Access onto Python.

Chapter 2: Meet the Band

Chapter 3: The "Seriousness" of Access Compatibility

The commandments carved into development rules

"Improvements prohibited."

Normal engineers would resist. "There's a better way to write this."

But Paccess is different. "Behaving the same as Access version" — that's the only justice.

AccessTextBox — Perfect recreation of "dated" design

Focus turns it light blue. That 90s Access behavior.

We could have built a modern UI with PySide6. Flat design, material design — plenty of ways to make it "contemporary."

But we didn't.

Why? Because there are users who've been accustomed to that light blue for 20 years.

Chapter 4: DataMapper — Reinventing Bound Controls

The aesthetics of declarative binding

Access had "bound controls." Just set ControlSource on a textbox and it auto-syncs with DB columns.

Paccess recreated this in Python.

self.mapper.add_mapping(widget_a, "ColumnA", DataType.STR)
self.mapper.add_mapping(widget_b, "ColumnB", DataType.MONEY)
self.mapper.add_mapping(widget_c, "ColumnC", DataType.DATE)

Three lines, three widgets synced with the database.

Press save, and DataMapper collects all widget values, builds SQL, and pushes it to the DB.

Recreating Access productivity in Python.

Chapter 5: BaseRecordForm — The Soul of Access Forms

Complete recreation of form "conventions"

Access forms had implicit "conventions":

• ▶ Navigate between records via navigation bar
• ▶ Editing makes it "dirty"
• ▶ "Save changes?" when closing
• ▶ New records added at the end

All of this is implemented in BaseRecordForm.

Developers creating new screens just inherit this class and write only the differences.

Create Python screens with the same feel as creating Access forms.

Chapter 6: ObservableConnection — The Silent Watcher

Log all SQL with one line

# Before
conn = sqlite3.connect("database.db")

# After
conn = ObservableConnection("database.db")

That's it. All SQL is automatically logged.

Business logic untouched. Three types of logs auto-generated:

• ▶ Operation history log
• ▶ Audit log (data changes only)
• ▶ Error log

Victory for the Observer pattern.

Chapter 7: Track List

Disc 1: Core Framework

Disc 2: Infrastructure

Disc 3: UI Components

Chapter 8: Why Paccess is "The Real Thing"

Respect for "working systems"

Systems that have run for 20 years have their reasons.

Even behavior that looks like a bug may have supported someone's workflow.

Understand it, respect it, recreate it. That's Paccess's philosophy.

Few can build compatibility layers

The people who wrote this code:

• ▶ Know all Access features intimately
• ▶ Know PySide6 intimately
• ▶ Know framework design intimately
• ▶ And can develop under the constraint of "not breaking Access behavior"

People who meet all these criteria are rare worldwide.

Recommend if you like:
The resolve to fight between legacy and modern, the thrill of differential programming

FFO (For Fans Of):
Wine, Mono, ReactOS — pioneers of compatibility layers

Final Verdict: Hall of Fame

The people who built this are undoubtedly "the real thing."