diff --git a/src/flatten/index.spec.ts b/src/flatten/index.spec.ts
index 5cbbddb..e70e122 100644
--- a/src/flatten/index.spec.ts
+++ b/src/flatten/index.spec.ts
@@ -2,6 +2,16 @@ import { Ainsley, AinsleyChild } from '../types'
 import { flatten } from '.'
 
 describe('flatten', () => {
+  test('invalid config', async () => {
+    await flatten((null as unknown) as Ainsley)
+      .then(() => {
+        expect(1).toBe(2)
+      })
+      .catch((err) => {
+        expect(err.message).toMatch(/^Invalid input Ainsley:/)
+      })
+  })
+
   test('mock getConfig', async () => {
     const start: Ainsley = {
       children: ['$not-a-real-config', 'body{margin:0}']
diff --git a/src/generate/index.spec.ts b/src/generate/index.spec.ts
index c5ca4db..5ccbca6 100644
--- a/src/generate/index.spec.ts
+++ b/src/generate/index.spec.ts
@@ -517,4 +517,365 @@ describe('compiler', () => {
       '.cB{color:black}.cW{color:white}.bgcB{background-color:black}.bgcW{background-color:white}.bgcG{background-color:#777}.bcB{border-color:black}.bcW{border-color:white}.bcG{border-color:#777}.bcY{border-color:#ff0}@media(min-width:1024px){.l-bcB{border-color:black}.l-bcW{border-color:white}.l-bcG{border-color:#777}.l-bcY{border-color:#ff0}}@media(min-width:768px){.m-bgcB{background-color:black}.m-bgcW{background-color:white}.m-bgcG{background-color:#777}.m-bcB{border-color:black}.m-bcW{border-color:white}.m-bcG{border-color:#777}.m-bcY{border-color:#ff0}@media(min-width:1024px){.l-m-bcB{border-color:black}.l-m-bcW{border-color:white}.l-m-bcG{border-color:#777}.l-m-bcY{border-color:#ff0}}}@media(min-width:384px){.s-cB{color:black}.s-cW{color:white}.s-bgcB{background-color:black}.s-bgcW{background-color:white}.s-bgcG{background-color:#777}.s-bcB{border-color:black}.s-bcW{border-color:white}.s-bcG{border-color:#777}.s-bcY{border-color:#ff0}@media(min-width:1024px){.l-s-bcB{border-color:black}.l-s-bcW{border-color:white}.l-s-bcG{border-color:#777}.l-s-bcY{border-color:#ff0}}@media(min-width:768px){.m-s-bgcB{background-color:black}.m-s-bgcW{background-color:white}.m-s-bgcG{background-color:#777}.m-s-bcB{border-color:black}.m-s-bcW{border-color:white}.m-s-bcG{border-color:#777}.m-s-bcY{border-color:#ff0}@media(min-width:1024px){.l-m-s-bcB{border-color:black}.l-m-s-bcW{border-color:white}.l-m-s-bcG{border-color:#777}.l-m-s-bcY{border-color:#ff0}}}}'
     )
   })
+
+  test.only('apparently this crashes', () => {
+    const css = generate({
+      children: [
+        '*,::after,::before{box-sizing:border-box;outline-offset:0;border:0 solid}[type=button],[type=date],[type=datetime-local],[type=email],[type=file],[type=image],[type=month],[type=number],[type=password],[type=reset],[type=search],[type=submit],[type=tel],[type=text],[type=time],[type=url],[type=week],a,abbr,acronym,address,applet,article,aside,audio,b,big,blockquote,body,button,canvas,caption,center,cite,code,dd,del,details,dfn,div,dl,dt,em,embed,fieldset,figcaption,figure,footer,form,h1,h2,h3,h4,h5,h6,header,hgroup,html,i,iframe,img,ins,kbd,label,legend,li,mark,menu,nav,object,ol,output,p,pre,q,ruby,s,samp,section,small,span,strike,strong,sub,summary,sup,time,tt,u,ul,var,video{margin:0;padding:0;border:0 solid;background:0 0;font:inherit;color:inherit;text-align:inherit;vertical-align:baseline}article,aside,details,figcaption,figure,footer,header,hgroup,menu,nav,section{display:block}html{overflow-y:scroll;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}ol,ul{list-style:none}blockquote,q{quotes:none}blockquote::after,blockquote::before,q::after,q::before{content:none}textarea{resize:vertical;overflow:auto}applet,canvas,img,object,svg,video{max-width:100%;height:auto}',
+        {
+          children: [
+            ['', [['{scalar}', '{scale}']]],
+            ['', [['{direction}', '{scale}']]],
+            ['', [['{flexCrossAxes}', '{flexCrossAxis}']]],
+            ['c', [['color', '{colors}']]],
+            ['bac', [['background-color', '{colors}']]],
+            [
+              'fosz',
+              [
+                ['font-size', '{typeScale}'],
+                ['line-height', 1.2]
+              ]
+            ],
+            ['pa', [['padding', '{scale}']]],
+            ['pa', [['padding-{direction}', '{scale}']]],
+            ['bap', [['background-position', '{xLoc} {yLoc}']]],
+            ['bo', [['border-{direction}', '{scale} solid {colors}']]],
+            ['fl', [['flex', '{flexChange} {flexChange} {flexBasis}']]],
+            ['ov', [['overflow', '{overflow} {overflow}']]],
+            [
+              'Display',
+              {
+                i: 'inline',
+                b: 'block',
+                fx: 'flex',
+                n: 'none',
+                ib: 'inline-block',
+                ifx: 'inline-flex'
+              }
+            ],
+            [
+              'Text-Decoration',
+              {
+                l: 'line-through',
+                u: 'underline',
+                n: 'none'
+              }
+            ],
+            [
+              'FOnt-STyle',
+              {
+                i: 'italic',
+                n: 'normal'
+              }
+            ],
+            [
+              'Text-TransForm',
+              {
+                u: 'uppercase',
+                l: 'lowercase'
+              }
+            ],
+            [
+              'OVerflow-Wrap',
+              {
+                bw: 'break-word',
+                a: 'anywhere',
+                n: 'normal'
+              }
+            ],
+            [
+              'BAckground-Repeat',
+              {
+                r: 'repeat',
+                n: 'no-repeat'
+              }
+            ],
+            [
+              'Position',
+              {
+                r: 'relative',
+                a: 'absolute',
+                f: 'fixed',
+                s: 'sticky'
+              }
+            ],
+            [
+              'Text-Align',
+              {
+                l: 'left',
+                c: 'center',
+                r: 'right',
+                j: 'justify'
+              }
+            ],
+            [
+              'Vertical-Align',
+              {
+                t: 'top',
+                m: 'middle',
+                b: 'bottom'
+              }
+            ],
+            [
+              'CUrsor',
+              {
+                d: 'default',
+                p: 'pointer'
+              }
+            ],
+            [
+              'Pointer-Events',
+              {
+                n: 'none',
+                a: 'all'
+              }
+            ],
+            [
+              'Z-Index',
+              {
+                0: '0',
+                1: '1',
+                2: '2',
+                4: '4',
+                8: '8',
+                16: '16',
+                32: '32'
+              }
+            ],
+            [
+              'Opacity',
+              {
+                0: '0',
+                10: '10',
+                20: '20',
+                40: '40',
+                80: '80',
+                100: '100'
+              }
+            ],
+            [
+              'White-Space',
+              {
+                p: 'pre',
+                pw: 'pre-wrap',
+                nw: 'nowrap',
+                n: 'normal'
+              }
+            ],
+            [
+              'BAckground-SiZe',
+              {
+                cv: 'cover',
+                ct: 'contain'
+              }
+            ],
+            [
+              'FLex-Direction',
+              {
+                r: 'row',
+                c: 'column',
+                rr: 'row-reverse',
+                cr: 'column-reverse'
+              }
+            ],
+            [
+              'Justify-Content',
+              {
+                c: 'center',
+                fs: 'flex-start',
+                fe: 'flex-end',
+                sb: 'space-between',
+                se: 'space-evenly'
+              }
+            ],
+            ['Line-Height', { B: 1, T: 1.2, C: 1.3 }],
+            ['FOnt-Weight', { N: 400, M: 600, B: 700 }],
+            {
+              variables: {
+                '+scale': {
+                  N1: '-1px',
+                  N2: '-2px',
+                  N3: '-3px',
+                  N10: '-4px',
+                  N15: '-6px',
+                  N20: '-8px',
+                  N25: '-12px',
+                  N30: '-16px',
+                  N35: '-24px',
+                  N40: '-32px',
+                  N45: '-48px',
+                  N50: '-64px',
+                  N55: '-96px',
+                  N60: '-128px',
+                  N65: '-192px',
+                  N70: '-256px',
+                  N75: '-384px',
+                  N80: '-512px',
+                  N85: '-768px',
+                  N90: '-1024px',
+                  N95: '-1536px',
+                  NP50: '-50%',
+                  NP: '-100%',
+                  NH: '-100vh',
+                  NW: '-100vw',
+                  NX: '-11111111px'
+                }
+              },
+              children: [
+                ['ma', [['margin', '{scale}']]],
+                ['ma', [['margin-{direction}', '{scale}']]]
+              ]
+            }
+          ],
+          variables: {
+            '?overflow': {
+              h: 'hidden',
+              s: 'scroll',
+              a: 'auto',
+              v: 'visible'
+            },
+            '?flexCrossAxes': {
+              ai: 'align-items',
+              as: 'align-self',
+              ac: 'align-content'
+            },
+            '?flexCrossAxis': {
+              fs: 'flex-start',
+              fe: 'flex-end',
+              c: 'center',
+              b: 'baseline',
+              s: 'stretch'
+            },
+            '?flexChange': {
+              0: '0',
+              1: '1',
+              2: '2',
+              x: '11111111'
+            },
+            '?flexBasis': {
+              0: '0%',
+              a: 'auto',
+              p: '100%'
+            },
+            '?xLoc': {
+              l: 'left',
+              r: 'right',
+              c: 'center'
+            },
+            '?yLoc': {
+              t: 'top',
+              b: 'bottom',
+              c: 'center'
+            },
+            '?scalar': {
+              w: 'width',
+              xw: 'max-width',
+              nw: 'min-width',
+              h: 'height',
+              xh: 'max-height',
+              nh: 'min-height',
+              bor: 'border-radius'
+            },
+            '?direction': {
+              t: 'top',
+              l: 'left',
+              r: 'right',
+              b: 'bottom'
+            },
+            '?colors': {
+              W: 'white',
+              B: 'black',
+              TR: 'transparent',
+              G98: 'hsl(0,0%,98%)',
+              G94: 'hsl(0,0%,94%)',
+              G88: 'hsl(0,0%,88%)',
+              G80: 'hsl(0,0%,80%)',
+              G30: 'hsl(0,0%,30%)',
+              G20: 'hsl(0,0%,20%)',
+              G10: 'hsl(0,0%,10%)',
+              B05: 'hsla(0,0%,0%,05%)',
+              B10: 'hsla(0,0%,0%,10%)',
+              B20: 'hsla(0,0%,0%,20%)',
+              B40: 'hsla(0,0%,0%,40%)',
+              B80: 'hsla(0,0%,0%,80%)',
+              W05: 'hsla(0,0%,100%,05%)',
+              W10: 'hsla(0,0%,100%,10%)',
+              W20: 'hsla(0,0%,100%,20%)',
+              W40: 'hsla(0,0%,100%,40%)',
+              W80: 'hsla(0,0%,100%,80%)',
+              PRIMARY: '#8d1d90',
+              ALTPRIMARY: '#9d3ea0',
+              SECONDARY: '#b7de58',
+              ALTSECONDARY: '#c1e270',
+              GOOD: '#3bb273',
+              LIGHTGOOD: '#ebf7f1',
+              WARN: '#e1bc29',
+              LIGHTWARN: '#fcf8e9',
+              BAD: '#e15554',
+              LIGHTBAD: '#fceeed',
+              MSG: '#3d70b2',
+              LIGHTMSG: '#ebf0f7'
+            },
+            '?typeScale': {
+              h1: '72px',
+              h2: '48px',
+              h3: '32px',
+              h4: '24px',
+              h5: '20px',
+              lg: '20px',
+              md: '16px',
+              sm: '14px',
+              xs: '12px'
+            },
+            '?scale': {
+              0: '0',
+              1: '1px',
+              2: '2px',
+              3: '3px',
+              10: '4px',
+              15: '6px',
+              20: '8px',
+              25: '12px',
+              30: '16px',
+              35: '24px',
+              40: '32px',
+              45: '48px',
+              50: '64px',
+              55: '96px',
+              60: '128px',
+              65: '192px',
+              70: '256px',
+              75: '384px',
+              80: '512px',
+              85: '768px',
+              90: '1024px',
+              95: '1536px',
+              p50: '50%',
+              p: '100%',
+              h: '100vh',
+              w: '100vw',
+              x: '11111111px'
+            }
+          },
+          variations: [
+            [
+              ['o', ':hover'],
+              ['o', ':focus'],
+              ['o', ':active']
+            ],
+            [
+              ['s', '@media(min-width:384px)'],
+              ['m', '@media(min-width:768px)'],
+              ['l', '@media(min-width:1024px)'],
+              ['x', '@media(min-width:1536px)']
+            ]
+          ]
+        }
+      ]
+    })
+
+    expect(css).toEqual(
+      '.cB{color:black}.cW{color:white}.bgcB{background-color:black}.bgcW{background-color:white}.bgcG{background-color:#777}.bcB{border-color:black}.bcW{border-color:white}.bcG{border-color:#777}.bcY{border-color:#ff0}@media(min-width:1024px){.l-bcB{border-color:black}.l-bcW{border-color:white}.l-bcG{border-color:#777}.l-bcY{border-color:#ff0}}@media(min-width:768px){.m-bgcB{background-color:black}.m-bgcW{background-color:white}.m-bgcG{background-color:#777}.m-bcB{border-color:black}.m-bcW{border-color:white}.m-bcG{border-color:#777}.m-bcY{border-color:#ff0}@media(min-width:1024px){.l-m-bcB{border-color:black}.l-m-bcW{border-color:white}.l-m-bcG{border-color:#777}.l-m-bcY{border-color:#ff0}}}@media(min-width:384px){.s-cB{color:black}.s-cW{color:white}.s-bgcB{background-color:black}.s-bgcW{background-color:white}.s-bgcG{background-color:#777}.s-bcB{border-color:black}.s-bcW{border-color:white}.s-bcG{border-color:#777}.s-bcY{border-color:#ff0}@media(min-width:1024px){.l-s-bcB{border-color:black}.l-s-bcW{border-color:white}.l-s-bcG{border-color:#777}.l-s-bcY{border-color:#ff0}}@media(min-width:768px){.m-s-bgcB{background-color:black}.m-s-bgcW{background-color:white}.m-s-bgcG{background-color:#777}.m-s-bcB{border-color:black}.m-s-bcW{border-color:white}.m-s-bcG{border-color:#777}.m-s-bcY{border-color:#ff0}@media(min-width:1024px){.l-m-s-bcB{border-color:black}.l-m-s-bcW{border-color:white}.l-m-s-bcG{border-color:#777}.l-m-s-bcY{border-color:#ff0}}}}'
+    )
+  })
 })
diff --git a/src/generate/index.ts b/src/generate/index.ts
index 81133f6..82f049b 100644
--- a/src/generate/index.ts
+++ b/src/generate/index.ts
@@ -129,7 +129,7 @@ const ainsleyToAst = (
       const modAndBase = parseVariable(variable)
       const mod = modAndBase[0]
       const base = modAndBase[1]
-      if (mod === 0) {
+      if (mod === 0 || (mod === 1 && newVariables[base] === undefined)) {
         newVariables[base] = variables[variable]
       } else if (mod === 2) {
         newVariables[base] = {
@@ -210,6 +210,11 @@ const ainsleyRuleToAst = (
       const iterator = iteratorAndType[0]
       const location = iteratorAndType[1]
       const variableName = iterator.slice(1, -1)
+
+      if (!(variableName in variables)) {
+        console.log(variables, variableName)
+      }
+
       return Object.keys(variables[variableName]).map(
         (abbreviation: string): AinsleyGenerateIteratorContext => [
           iterator,