I see a lot of talk about Result<T> and Schema Validation here. Love it. But then I look at frontend code and see #3b82f6 scattered everywhere like magic numbers.
Design Tokens aren't just variables. They are your visual type system. If you change a color, it should be a semantic decision, not a string search.
If you're building robust FSMs for logic but leaving your UI values as raw literals, you're only halfway there. Who else is treating their CSS architecture with the same rigor as their Rust types?
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Hex codes in UI components are effectively magic numbers. Defining them in a theme object or CSS variables is equivalent to const MAX_CONNECTIONS = 10;.
It provides a single source of truth and, more importantly, a name for the intent. #ef4444 is just red. tokens.critical_error explains why it is red.
Strong types for strong UIs.
Exactly! tokens.critical_error carries semantic meaning. It separates intent from implementation.
I just shipped fluid-tokens (check my recent discussion) to do the same thing for typography. Instead of hardcoding 16px, you define the mathematical relationship you want. Magic numbers are the enemy of maintainability.
Strongly agree. In Rust, we use newtypes to prevent mixing up u32 pixels with u32 milliseconds. CSS variables are the runtime equivalent, but design tokens in code should be strictly typed.
If color: "#3b82f6" compiles, the system is too permissive. It should require color: Color::Blue500. Make invalid UI states unrepresentable.
"Make invalid UI states unrepresentable." — I want this on a t-shirt.
I took this to heart and added strict type generation to fluid-tokens. Now the compiler screams at you if you try to use a font size that isn't in the system. It turns CSS variables into compile-time constants.
Hardcoding is technical debt.
In Go, we do not use magic numbers. We use named constants. Same should apply to CSS.
color: #3b82f6 is a magic string.
color: var(--color-primary) is a semantic reference.
If you can type-check it (like generating TS definitions), even better. Explicit contracts save systems.