I think it'll work

src/alf/styles.ts

@@ -260,6 +260,9 @@ export const styles = {
     ...fontSize,
     ...fontWeight,
     ...lineHeight,
+    center: {
+      textAlign: 'center',
+    },
   },
   flex: {
     gap,
@@ -281,6 +284,12 @@ export const styles = {
     alignCenter: {
       alignItems: 'center',
     },
+    alignStart: {
+      alignItems: 'flex-start',
+    },
+    alignEnd: {
+      alignItems: 'flex-end',
+    },
     justifyCenter: {
       justifyContent: 'center',
     },

src/view/com/Button.tsx

@@ -1,32 +1,199 @@
 import React from 'react'
-import {Pressable, Text} from 'react-native'
+import {Pressable, Text, PressableProps, TextProps} from 'react-native'
 import {useAlf, tokens} from '#/alf'
 
-export function Button({children, ...rest}: React.PropsWithChildren<any>) {
+export type ButtonType =
+  | 'primary'
+  | 'secondary'
+  | 'tertiary'
+  | 'positive'
+  | 'negative'
+export type ButtonSize = 'small' | 'large'
+
+export type VariantProps = {
+  type?: ButtonType
+  size?: ButtonSize
+}
+type ButtonState = {
+  pressed: boolean
+  hovered: boolean
+  focused: boolean
+}
+export type ButtonProps = Omit<PressableProps, 'children'> &
+  VariantProps & {
+    children:
+      | ((props: {
+          state: ButtonState
+          type?: ButtonType
+          size?: ButtonSize
+        }) => React.ReactNode)
+      | React.ReactNode
+      | string
+  }
+export type ButtonTextProps = TextProps & VariantProps
+
+export function Button({children, style, type, size, ...rest}: ButtonProps) {
   const {styles} = useAlf()
+  const {baseStyles, hoverStyles} = React.useMemo(() => {
+    const baseStyles = []
+    const hoverStyles = []
+
+    switch (type) {
+      case 'primary':
+        baseStyles.push(styles.backgroundColor.primary)
+        break
+      case 'secondary':
+        baseStyles.push(styles.backgroundColor.l2)
+        hoverStyles.push(styles.backgroundColor.l1)
+        break
+      default:
+    }
+
+    switch (size) {
+      case 'large':
+        baseStyles.push(
+          styles.padding.py.m,
+          styles.padding.px.xl,
+          styles.radius.m,
+          styles.flex.gap.s,
+        )
+        break
+      case 'small':
+        baseStyles.push(
+          styles.padding.py.s,
+          styles.padding.px.m,
+          styles.radius.s,
+          styles.flex.gap.xs,
+        )
+        break
+      default:
+    }
+
+    return {
+      baseStyles,
+      hoverStyles,
+    }
+  }, [type, size, styles])
+
+  const [state, setState] = React.useState({
+    pressed: false,
+    hovered: false,
+    focused: false,
+  })
+
+  const onPressIn = React.useCallback(() => {
+    setState(s => ({
+      ...s,
+      pressed: true,
+    }))
+  }, [setState])
+  const onPressOut = React.useCallback(() => {
+    setState(s => ({
+      ...s,
+      pressed: false,
+    }))
+  }, [setState])
+  const onHoverIn = React.useCallback(() => {
+    setState(s => ({
+      ...s,
+      hovered: true,
+    }))
+  }, [setState])
+  const onHoverOut = React.useCallback(() => {
+    setState(s => ({
+      ...s,
+      hovered: false,
+    }))
+  }, [setState])
+  const onFocus = React.useCallback(() => {
+    setState(s => ({
+      ...s,
+      focused: true,
+    }))
+  }, [setState])
+  const onBlur = React.useCallback(() => {
+    setState(s => ({
+      ...s,
+      focused: false,
+    }))
+  }, [setState])
+
   return (
     <Pressable
       {...rest}
-      style={[
+      style={state => [
         styles.flex.row,
-        styles.flex.gap.m,
-        styles.padding.px.m,
-        styles.padding.py.s,
-        styles.radius.m,
-        styles.backgroundColor.primary,
-      ]}>
+        styles.flex.alignCenter,
+        ...baseStyles,
+        ...(state.hovered ? hoverStyles : []),
+        typeof style === 'function' ? style(state) : style,
+      ]}
+      onPressIn={onPressIn}
+      onPressOut={onPressOut}
+      onHoverIn={onHoverIn}
+      onHoverOut={onHoverOut}
+      onFocus={onFocus}
+      onBlur={onBlur}>
       {typeof children === 'string' ? (
-        <Text
-          style={[
-            styles.font.s,
-            styles.font.semi,
-            {color: tokens.color.white},
-          ]}>
+        <ButtonText type={type} size={size}>
           {children}
-        </Text>
+        </ButtonText>
+      ) : typeof children === 'function' ? (
+        children({state, type, size})
       ) : (
         children
       )}
     </Pressable>
   )
 }
+
+export function ButtonText({
+  children,
+  style,
+  type,
+  size,
+  ...rest
+}: ButtonTextProps) {
+  const {styles} = useAlf()
+  const textStyles = React.useMemo(() => {
+    const base = []
+
+    switch (type) {
+      case 'primary':
+        base.push({color: tokens.color.white})
+        break
+      case 'secondary':
+        base.push(styles.color.l5)
+        break
+      default:
+    }
+
+    switch (size) {
+      case 'small':
+        base.push(styles.font.s, {paddingBottom: 1})
+        break
+      case 'large':
+        base.push(styles.font.m, {paddingBottom: 1})
+        break
+      default:
+    }
+
+    return base
+  }, [type, size, styles])
+
+  console.log(textStyles)
+
+  return (
+    <Text
+      {...rest}
+      style={[
+        styles.flex.one,
+        styles.font.semi,
+        styles.font.center,
+        ...textStyles,
+        style,
+      ]}>
+      {children}
+    </Text>
+  )
+}

src/view/screens/DebugNew.tsx

@@ -1,10 +1,11 @@
 import React from 'react'
 import {View} from 'react-native'
 import {CenteredView, ScrollView} from '#/view/com/util/Views'
+import {FontAwesomeIcon} from '@fortawesome/react-native-fontawesome'
 
 import {useSetColorMode} from '#/state/shell'
 import {useAlf, ThemeProvider as Alf} from '#/alf'
-import {Button} from '#/view/com/Button'
+import {Button, ButtonText} from '#/view/com/Button'
 import {Text, H1, H2, H3, H4, H5, H6} from '#/view/com/Typography'
 
 function ThemeSelector() {
@@ -13,9 +14,24 @@ function ThemeSelector() {
 
   return (
     <View style={[styles.flex.row, styles.flex.gap.m]}>
-      <Button onPress={() => setColorMode('system')}>System</Button>
-      <Button onPress={() => setColorMode('light')}>Light</Button>
-      <Button onPress={() => setColorMode('dark')}>Dark</Button>
+      <Button
+        type="secondary"
+        size="small"
+        onPress={() => setColorMode('system')}>
+        System
+      </Button>
+      <Button
+        type="secondary"
+        size="small"
+        onPress={() => setColorMode('light')}>
+        Light
+      </Button>
+      <Button
+        type="secondary"
+        size="small"
+        onPress={() => setColorMode('dark')}>
+        Dark
+      </Button>
     </View>
   )
 }
@@ -269,6 +285,56 @@ export function DebugScreen() {
           <Alf theme="light">
             <ThemedSection />
           </Alf>
+
+          <View style={[styles.flex.gap.m, styles.flex.alignStart]}>
+            <H3 style={[styles.padding.pb.m, styles.font.bold]}>Buttons</H3>
+
+            <Button>
+              {({state}) => (
+                <View
+                  style={[
+                    styles.padding.pa.m,
+                    styles.radius.round,
+                    styles.backgroundColor.l2,
+                  ]}>
+                  <Text>Unstyled button, state: {JSON.stringify(state)}</Text>
+                </View>
+              )}
+            </Button>
+
+            <Button type="primary" size="small">
+              Button
+            </Button>
+            <Button type="secondary" size="small">
+              Button
+            </Button>
+
+            <Button type="primary" size="large">
+              Button
+            </Button>
+            <Button type="secondary" size="large">
+              Button
+            </Button>
+
+            <Button type="secondary" size="small">
+              {({type, size}) => (
+                <>
+                  <FontAwesomeIcon icon={['fas', 'plus']} size={12} />
+                  <ButtonText type={type} size={size}>
+                    With an icon
+                  </ButtonText>
+                </>
+              )}
+            </Button>
+            <Button type="primary" size="large">
+              {({state: _state, ...rest}) => (
+                <>
+                  <FontAwesomeIcon icon={['fas', 'plus']} />
+                  <ButtonText {...rest}>With an icon</ButtonText>
+                </>
+              )}
+            </Button>
+          </View>
         </View>
       </CenteredView>
     </ScrollView>