diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4a04a0c..2c64785 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+# 1.18
+
+- Add `sourceDialects`
+
 # 1.17
 
 - Add `module` field if a top-level `esm` export exists for
diff --git a/README.md b/README.md
index 472ae33..1989255 100644
--- a/README.md
+++ b/README.md
@@ -874,10 +874,12 @@ for code hints in VSCode, neovim, tests, etc.
 
 ### Loading from Source
 
-If you are using tshy in a monorepo environment, you can
-configure TypeScript (and other tools) to resolve to the _source_
-files rather than built artifacts by telling them to use the
-`"source"` export condition.
+To facilitate jumping directly to source definitions in some
+tools, you can define custom `"sourceDialects"` which will be
+resolved to the original TypeScript source. These custom dialects
+can then be configured to allow build tools (such as tsc) and
+editors (such as VS Code and neovim/CoC) to jump directly to
+source definitions.
 
 For example, in editors such as VS Code and neovim/CoC that use
 the TypeScript language services, you can give them a `tsconfig`
@@ -886,7 +888,17 @@ that contains this:
 ```json
 {
   "compilerOptions": {
-    "customConditions": ["source"]
+    "customConditions": ["@my-project/source"]
+  }
+}
+```
+
+And then add this to your `package.json` file:
+
+```json
+{
+  "tshy": {
+    "sourceDialects": ["@my-project/source"]
   }
 }
 ```
@@ -896,7 +908,7 @@ like [`tsx`](https://npm.im/tsx) that can load TypeScript
 directly, you can specify it like this:
 
 ```bash
-node --import=tsx --conditions=source ./script.ts
+node --import=tsx --conditions=@my-project/source ./script.ts
 ```
 
 Other TypeScript-aware tools may have other mechanisms for
@@ -905,6 +917,16 @@ more information.
 
 See also: "Live Dev", above.
 
+#### Why not just use `"source"` as the target?
+
+Tshy always builds the `"source"` target referencing the location
+of the TypeScript file that was built. However, this can cause
+problems if tools use this to resolve into dependencies, which
+may not ship their TypeScript source.
+
+But if you can configure your tools to _only_ use this import
+condition outside of `node_modules`, then it's safe to use.
+
 ### Custom `project`
 
 Configure `tshy.project` if you want tshy to extend from a custom
diff --git a/src/exports.ts b/src/exports.ts
index 497e05a..aba1e8d 100644
--- a/src/exports.ts
+++ b/src/exports.ts
@@ -91,6 +91,9 @@ const getExports = (
       continue
     }
 
+    /* c8 ignore next - already guarded */
+    if (s === null) continue
+
     const impTarget = getImpTarget(s, polyfills)
     const reqTarget = getReqTarget(s, polyfills)
 
@@ -116,10 +119,12 @@ const getExports = (
             liveDev ?
               {
                 source,
+                ...getSourceDialects(source, c),
                 default: target,
               }
             : {
                 source,
+                ...getSourceDialects(source, c),
                 types: target.replace(/\.js$/, '.d.ts'),
                 default: target,
               }
@@ -142,10 +147,12 @@ const getExports = (
             liveDev ?
               {
                 source,
+                ...getSourceDialects(source, c),
                 default: target,
               }
             : {
                 source,
+                ...getSourceDialects(source, c),
                 types: target.replace(/\.js$/, '.d.ts'),
                 default: target,
               }
@@ -183,6 +190,12 @@ const getExports = (
   return e
 }
 
+const getSourceDialects = (source: string, c: TshyConfig) => {
+  const { sourceDialects } = c
+  if (!sourceDialects) return {}
+  return Object.fromEntries(sourceDialects.map(s => [s, source]))
+}
+
 export const setMain = (
   c: TshyConfig | undefined,
   pkg: Package & { exports: ExportsSubpaths },
diff --git a/src/tsconfig.ts b/src/tsconfig.ts
index 7e357e5..4e3d9e1 100644
--- a/src/tsconfig.ts
+++ b/src/tsconfig.ts
@@ -23,7 +23,9 @@ const {
   exclude = [],
 } = config
 
-const relativeExclude = exclude.map(e => `../${e.replace(/^\.\//, '')}`)
+const relativeExclude = exclude.map(
+  e => `../${e.replace(/^\.\//, '')}`,
+)
 
 const recommended: Record<string, any> = {
   compilerOptions: {
diff --git a/src/types.ts b/src/types.ts
index fda64d8..4ce44c4 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -12,6 +12,7 @@ export type TshyConfigMaybeGlobExports = {
   module?: boolean
   commonjsDialects?: string[]
   esmDialects?: string[]
+  sourceDialects?: string[]
   project?: string
   exclude?: string[]
   liveDev?: boolean
diff --git a/src/valid-extra-dialects.ts b/src/valid-extra-dialects.ts
index 07e5f56..c80edfb 100644
--- a/src/valid-extra-dialects.ts
+++ b/src/valid-extra-dialects.ts
@@ -8,16 +8,14 @@ const arrayOverlap = (
 ): string | false => {
   if (!a || !b) return false
   for (const av of a) {
-    if (b.includes(av)) {
-      return av
-    }
+    if (b.includes(av)) return av
   }
   return false
 }
 
 const validExtraDialectSet = (
   e: string[],
-  which: 'commonjs' | 'esm',
+  which: 'commonjs' | 'esm' | 'source',
 ) => {
   for (const d of e) {
     if (typeof d !== 'string') {
@@ -31,17 +29,28 @@ const validExtraDialectSet = (
       d === 'require' ||
       d === 'import' ||
       d === 'node' ||
+      d === 'source' ||
       d === 'default'
     ) {
-      fail(`${which} must not contain ${d}`)
+      fail(
+        `tshy.${which}Dialects must not contain ${JSON.stringify(d)}`,
+      )
       return process.exit(1)
     }
   }
   return true
 }
 
-export default ({ commonjsDialects, esmDialects }: TshyConfig) => {
-  if (commonjsDialects === undefined && esmDialects === undefined) {
+export default ({
+  commonjsDialects,
+  esmDialects,
+  sourceDialects,
+}: TshyConfig) => {
+  if (
+    commonjsDialects === undefined &&
+    esmDialects === undefined &&
+    sourceDialects === undefined
+  ) {
     return true
   }
   if (
@@ -53,11 +62,31 @@ export default ({ commonjsDialects, esmDialects }: TshyConfig) => {
   if (esmDialects && !validExtraDialectSet(esmDialects, 'esm')) {
     return false
   }
-  const overlap = arrayOverlap(commonjsDialects, esmDialects)
-  if (overlap) {
+  if (
+    sourceDialects &&
+    !validExtraDialectSet(sourceDialects, 'source')
+  ) {
+    return false
+  }
+  for (const [aname, bname, a, b] of [
+    [
+      'commonjsDialects',
+      'esmDialects',
+      commonjsDialects,
+      esmDialects,
+    ],
+    [
+      'commonjsDialects',
+      'sourceDialects',
+      commonjsDialects,
+      sourceDialects,
+    ],
+    ['esmDialects', 'sourceDialects', esmDialects, sourceDialects],
+  ] as const) {
+    const overlap = arrayOverlap(a, b)
+    if (!overlap) continue
     fail(
-      'commonjsDialects and esmDialects must be unique, ' +
-        `found ${overlap} in both lists`,
+      `${aname} and ${bname} must be unique, found ${overlap} in both lists`,
     )
     return process.exit(1)
   }
diff --git a/tap-snapshots/test/exports.ts.test.cjs b/tap-snapshots/test/exports.ts.test.cjs
index c520e44..5b7a937 100644
--- a/tap-snapshots/test/exports.ts.test.cjs
+++ b/tap-snapshots/test/exports.ts.test.cjs
@@ -29,6 +29,7 @@ Object {
   ".": Object {
     "blah": Object {
       "source": "./src/index.ts",
+      "my-source": "./src/index.ts",
       "types": "./dist/blah/index.d.ts",
       "default": "./dist/blah/index.js",
     },
@@ -41,6 +42,7 @@ Object {
   "./foo": Object {
     "blah": Object {
       "source": "./src/foo.ts",
+      "my-source": "./src/foo.ts",
       "types": "./dist/blah/foo.d.ts",
       "default": "./dist/blah/foo.js",
     },
@@ -77,11 +79,13 @@ Object {
   ".": Object {
     "deno": Object {
       "source": "./src/index.ts",
+      "my-source": "./src/index.ts",
       "types": "./dist/deno/index.d.ts",
       "default": "./dist/deno/index.js",
     },
     "no-overrides": Object {
       "source": "./src/index.ts",
+      "my-source": "./src/index.ts",
       "types": "./dist/no-overrides/index.d.ts",
       "default": "./dist/no-overrides/index.js",
     },
@@ -94,11 +98,13 @@ Object {
   "./foo": Object {
     "deno": Object {
       "source": "./src/foo.ts",
+      "my-source": "./src/foo.ts",
       "types": "./dist/deno/foo.d.ts",
       "default": "./dist/deno/foo.js",
     },
     "no-overrides": Object {
       "source": "./src/foo.ts",
+      "my-source": "./src/foo.ts",
       "types": "./dist/no-overrides/foo.d.ts",
       "default": "./dist/no-overrides/foo.js",
     },
@@ -145,16 +151,19 @@ Object {
   ".": Object {
     "deno": Object {
       "source": "./src/index.ts",
+      "my-source": "./src/index.ts",
       "types": "./dist/deno/index.d.ts",
       "default": "./dist/deno/index.js",
     },
     "no-overrides": Object {
       "source": "./src/index.ts",
+      "my-source": "./src/index.ts",
       "types": "./dist/no-overrides/index.d.ts",
       "default": "./dist/no-overrides/index.js",
     },
     "blah": Object {
       "source": "./src/index.ts",
+      "my-source": "./src/index.ts",
       "types": "./dist/blah/index.d.ts",
       "default": "./dist/blah/index.js",
     },
@@ -172,16 +181,19 @@ Object {
   "./foo": Object {
     "deno": Object {
       "source": "./src/foo.ts",
+      "my-source": "./src/foo.ts",
       "types": "./dist/deno/foo.d.ts",
       "default": "./dist/deno/foo.js",
     },
     "no-overrides": Object {
       "source": "./src/foo.ts",
+      "my-source": "./src/foo.ts",
       "types": "./dist/no-overrides/foo.d.ts",
       "default": "./dist/no-overrides/foo.js",
     },
     "blah": Object {
       "source": "./src/foo.ts",
+      "my-source": "./src/foo.ts",
       "types": "./dist/blah/foo.d.ts",
       "default": "./dist/blah/foo.js",
     },
diff --git a/tap-snapshots/test/valid-extra-dialects.ts.test.cjs b/tap-snapshots/test/valid-extra-dialects.ts.test.cjs
index deb43f8..76b8ec9 100644
--- a/tap-snapshots/test/valid-extra-dialects.ts.test.cjs
+++ b/tap-snapshots/test/valid-extra-dialects.ts.test.cjs
@@ -21,10 +21,18 @@ Array [
 ]
 `
 
+exports[`test/valid-extra-dialects.ts > TAP > {"esmDialects":["blah"],"sourceDialects":["blah"]} > failure message 1`] = `
+Array [
+  Array [
+    "esmDialects and sourceDialects must be unique, found blah in both lists",
+  ],
+]
+`
+
 exports[`test/valid-extra-dialects.ts > TAP > {"esmDialects":["cjs"]} > failure message 1`] = `
 Array [
   Array [
-    "esm must not contain cjs",
+    "tshy.esmDialects must not contain \\"cjs\\"",
   ],
 ]
 `
@@ -32,7 +40,7 @@ Array [
 exports[`test/valid-extra-dialects.ts > TAP > {"esmDialects":["commonjs"]} > failure message 1`] = `
 Array [
   Array [
-    "esm must not contain commonjs",
+    "tshy.esmDialects must not contain \\"commonjs\\"",
   ],
 ]
 `
@@ -40,7 +48,7 @@ Array [
 exports[`test/valid-extra-dialects.ts > TAP > {"esmDialects":["default"]} > failure message 1`] = `
 Array [
   Array [
-    "esm must not contain default",
+    "tshy.esmDialects must not contain \\"default\\"",
   ],
 ]
 `
@@ -48,7 +56,7 @@ Array [
 exports[`test/valid-extra-dialects.ts > TAP > {"esmDialects":["import"]} > failure message 1`] = `
 Array [
   Array [
-    "esm must not contain import",
+    "tshy.esmDialects must not contain \\"import\\"",
   ],
 ]
 `
@@ -56,7 +64,7 @@ Array [
 exports[`test/valid-extra-dialects.ts > TAP > {"esmDialects":["node"]} > failure message 1`] = `
 Array [
   Array [
-    "esm must not contain node",
+    "tshy.esmDialects must not contain \\"node\\"",
   ],
 ]
 `
@@ -64,7 +72,15 @@ Array [
 exports[`test/valid-extra-dialects.ts > TAP > {"esmDialects":["require"]} > failure message 1`] = `
 Array [
   Array [
-    "esm must not contain require",
+    "tshy.esmDialects must not contain \\"require\\"",
+  ],
+]
+`
+
+exports[`test/valid-extra-dialects.ts > TAP > {"esmDialects":["source"]} > failure message 1`] = `
+Array [
+  Array [
+    "tshy.esmDialects must not contain \\"source\\"",
   ],
 ]
 `
@@ -76,3 +92,19 @@ Array [
   ],
 ]
 `
+
+exports[`test/valid-extra-dialects.ts > TAP > {"sourceDialects":["blah"],"commonjsDialects":["blah"]} > failure message 1`] = `
+Array [
+  Array [
+    "commonjsDialects and sourceDialects must be unique, found blah in both lists",
+  ],
+]
+`
+
+exports[`test/valid-extra-dialects.ts > TAP > {"sourceDialects":["source"]} > failure message 1`] = `
+Array [
+  Array [
+    "tshy.sourceDialects must not contain \\"source\\"",
+  ],
+]
+`
diff --git a/test/exports.ts b/test/exports.ts
index 578f33b..71c8c34 100644
--- a/test/exports.ts
+++ b/test/exports.ts
@@ -342,6 +342,7 @@ t.test('extra dialects', async t => {
                 default: {
                   tshy: {
                     ...(extras && { esmDialects, commonjsDialects }),
+                    sourceDialects: ['my-source'],
                     dialects,
                     exports: {
                       '.': './src/index.ts',
diff --git a/test/valid-extra-dialects.ts b/test/valid-extra-dialects.ts
index 9bfb84f..664f136 100644
--- a/test/valid-extra-dialects.ts
+++ b/test/valid-extra-dialects.ts
@@ -19,12 +19,18 @@ const cases: [config: TshyConfig, ok: boolean][] = [
   [{ esmDialects: ['blah'] }, true],
   [{ esmDialects: ['blah'], commonjsDialects: ['blah'] }, false],
   [{ esmDialects: ['blah'], commonjsDialects: ['bloo'] }, true],
+  [{ sourceDialects: ['blah'], commonjsDialects: ['blah'] }, false],
+  [{ sourceDialects: ['blah'], commonjsDialects: ['bloo'] }, true],
+  [{ esmDialects: ['blah'], sourceDialects: ['blah'] }, false],
+  [{ esmDialects: ['blah'], sourceDialects: ['bloo'] }, true],
   [{ esmDialects: ['default'] }, false],
   [{ esmDialects: ['import'] }, false],
   [{ esmDialects: ['require'] }, false],
   [{ esmDialects: ['node'] }, false],
   [{ esmDialects: ['commonjs'] }, false],
   [{ esmDialects: ['cjs'] }, false],
+  [{ esmDialects: ['source'] }, false],
+  [{ sourceDialects: ['source'] }, false],
   //@ts-expect-error
   [{ esmDialects: [123] }, false],
   //@ts-expect-error