diff --git a/README.md b/README.md
index 908cc6f..230f1fb 100644
--- a/README.md
+++ b/README.md
@@ -63,55 +63,79 @@ The library is bundled and has no dependencies.
 
 ## Features
 
-- array mapper
-  - map elements to keys by order
-  - skip initial, gather remaining
-- async
-  - defer
-  - promise timeout
-  - wait for predicate
-- async tracker
-  - track and log leaking async resources for tests
-- buffer
-- checklist
-  - include/exclude mode (whitelist/blacklist)
-- child process
-  - wait for exit and gather output
-  - write and flush
-- env
-  - check `DEBUG`
-- list
-  - concat lists
-- logger
-  - get test logger (null or console depending on `DEBUG`)
-- map
-  - must get (assertion)
-  - get or default
-  - get head from list value
-  - get head or default
-  - set or push to key
-  - merge maps
-  - push-merge maps
-  - convert dict to map and vice versa
-  - normalize map values to lists
-  - create map from name-value pairs
-- maybe
-  - is nil test (negative nil test)
-  - count array or maybe
-  - filter nil from list
-  - must find (assertion)
-  - does exist (positive nil test)
-  - must exist (assertion)
-  - must default (assertion)
-- pid file
-  - write pid file
-  - delete pid file
-- reflect
-  - get constructor name
-  - get methods from prototype chain
-- signals
-  - wait for OS signal
-- string
-  - left pad (please don't import just for this)
-  - trim with suffix
+Features utilities and helpers for:
 
+- Array
+  - assertions/guards:
+    - `hasItems`
+    - `isArray` for both `Array`/`ReadonlyArray`
+    - `isEmpty`
+    - `lengthOf`
+  - conversion
+    - `filterZip`
+    - `toArray`
+- Array Mapper
+  - array-to-map converter, reduces an array of values to a map, using an array of keys
+- Async
+  - timed promises
+    - `defer`/`deferValue`
+    - `deferUntil`
+    - `timeout`
+- Buffer
+  - concatenation
+    - `concat`
+    - `encode`
+- Checklist
+  - allow/deny list
+- Child Process
+  - `childResult`
+  - `writeInput`
+- Env Vars
+  - `isDebug`
+- Logger
+  - test logging helpers
+- Map
+  - types
+    - `MapLike`
+  - assertions/guards:
+    - `mustGet`
+  - null-safe helpers
+    - `getOrDefault`
+  - helpers for `Map<K, Array<V>>`
+    - `getHead`/`getHeadOrDefault`
+    - `setOrPush`
+  - concat/merge
+    - `mergeMap`
+    - `pushMergeMap`
+  - conversion
+    - `entriesOf`
+    - `makeDict`
+    - `makeMap`
+    - `pairsToMap`
+- Math
+  - predicates for functional methods
+    - `sum`
+- Maybe
+  - types
+    - `Maybe`
+    - `None`
+  - assertions/guards
+    - `doesExist`
+    - `mustExist`
+    - `mustDefault`
+    - `mustFind`
+    - `removeNone`
+  - null-safe helpers
+    - `isNone`
+    - `isSome`
+- Predicate
+  - types for functional methods
+- Reflect
+  - `getConstructor`
+  - `getMethods`
+- Signal
+  - wait for OS signal
+    - `signal`
+- String
+  - `leftPad`
+  - `trim` with suffix
diff --git a/docs/api/js-utils.deferuntil.md b/docs/api/js-utils.deferuntil.md
new file mode 100644
index 0000000..1d41c32
--- /dev/null
+++ b/docs/api/js-utils.deferuntil.md
@@ -0,0 +1,30 @@
+<!-- Do not edit this file. It is automatically generated by API Documenter. -->
+
+[Home](./index.md) &gt; [@apextoaster/js-utils](./js-utils.md) &gt; [deferUntil](./js-utils.deferuntil.md)
+
+## deferUntil() function
+
+Reject after a set number of attempts if the given predicate does not return true.
+
+<b>Signature:</b>
+
+```typescript
+export declare function deferUntil(cb: PredicateC0, step: number, tries: number): Promise<void>;
+```
+
+## Parameters
+
+|  Parameter | Type | Description |
+|  --- | --- | --- |
+|  cb | PredicateC0 |  |
+|  step | number |  |
+|  tries | number |  |
+
+<b>Returns:</b>
+
+Promise&lt;void&gt;
+
+## Exceptions
+
+TimeoutError
+
diff --git a/docs/api/js-utils.externalmodule.data.md b/docs/api/js-utils.externalmodule.data.md
deleted file mode 100644
index 8cc84dc..0000000
--- a/docs/api/js-utils.externalmodule.data.md
+++ /dev/null
@@ -1,11 +0,0 @@
-<!-- Do not edit this file. It is automatically generated by API Documenter. -->
-
-[Home](./index.md) &gt; [@apextoaster/js-utils](./js-utils.md) &gt; [ExternalModule](./js-utils.externalmodule.md) &gt; [data](./js-utils.externalmodule.data.md)
-
-## ExternalModule.data property
-
-<b>Signature:</b>
-
-```typescript
-data?: unknown;
-```
diff --git a/docs/api/js-utils.externalmodule.export.md b/docs/api/js-utils.externalmodule.export.md
deleted file mode 100644
index 7719542..0000000
--- a/docs/api/js-utils.externalmodule.export.md
+++ /dev/null
@@ -1,11 +0,0 @@
-<!-- Do not edit this file. It is automatically generated by API Documenter. -->
-
-[Home](./index.md) &gt; [@apextoaster/js-utils](./js-utils.md) &gt; [ExternalModule](./js-utils.externalmodule.md) &gt; [export](./js-utils.externalmodule.export.md)
-
-## ExternalModule.export property
-
-<b>Signature:</b>
-
-```typescript
-export: string;
-```
diff --git a/docs/api/js-utils.externalmodule.md b/docs/api/js-utils.externalmodule.md
deleted file mode 100644
index e17c066..0000000
--- a/docs/api/js-utils.externalmodule.md
+++ /dev/null
@@ -1,20 +0,0 @@
-<!-- Do not edit this file. It is automatically generated by API Documenter. -->
-
-[Home](./index.md) &gt; [@apextoaster/js-utils](./js-utils.md) &gt; [ExternalModule](./js-utils.externalmodule.md)
-
-## ExternalModule interface
-
-<b>Signature:</b>
-
-```typescript
-export interface ExternalModule 
-```
-
-## Properties
-
-|  Property | Type | Description |
-|  --- | --- | --- |
-|  [data?](./js-utils.externalmodule.data.md) | unknown | <i>(Optional)</i> |
-|  [export](./js-utils.externalmodule.export.md) | string |  |
-|  [require](./js-utils.externalmodule.require.md) | string |  |
-
diff --git a/docs/api/js-utils.externalmodule.require.md b/docs/api/js-utils.externalmodule.require.md
deleted file mode 100644
index a499da4..0000000
--- a/docs/api/js-utils.externalmodule.require.md
+++ /dev/null
@@ -1,11 +0,0 @@
-<!-- Do not edit this file. It is automatically generated by API Documenter. -->
-
-[Home](./index.md) &gt; [@apextoaster/js-utils](./js-utils.md) &gt; [ExternalModule](./js-utils.externalmodule.md) &gt; [require](./js-utils.externalmodule.require.md)
-
-## ExternalModule.require property
-
-<b>Signature:</b>
-
-```typescript
-require: string;
-```
diff --git a/docs/api/js-utils.md b/docs/api/js-utils.md
index 6a85143..7567205 100644
--- a/docs/api/js-utils.md
+++ b/docs/api/js-utils.md
@@ -27,10 +27,12 @@
 
 |  Function | Description |
 |  --- | --- |
+|  [childResult(child)](./js-utils.childresult.md) | Wait for a child process to exit, collecting output, errors, and exit status. |
 |  [concat(chunks)](./js-utils.concat.md) | Concatenate a list of buffers. |
 |  [constructorName(val)](./js-utils.constructorname.md) | Get the constructor name from an instance. |
 |  [defaultWhen(condition, items)](./js-utils.defaultwhen.md) | Return the first element when <code>condition</code> is true and the second element when <code>condition</code> is false. |
 |  [defer(ms)](./js-utils.defer.md) | Resolve after a set amount of time. |
+|  [deferUntil(cb, step, tries)](./js-utils.deferuntil.md) | Reject after a set number of attempts if the given predicate does not return true. |
 |  [deferValue(ms, val)](./js-utils.defervalue.md) |  |
 |  [doesExist(val)](./js-utils.doesexist.md) | Check if a variable is some <code>T</code>. |
 |  [encode(chunks, encoding)](./js-utils.encode.md) | Concatenate then encode a list of buffers. |
@@ -77,14 +79,15 @@
 |  [removeNone(list)](./js-utils.removenone.md) | Remove any null or undefined items from the list. |
 |  [setOrPush(map, key, val)](./js-utils.setorpush.md) | Set a map key to a new array or push to the existing value. |
 |  [signal(signals)](./js-utils.signal.md) |  |
-|  [spyLogger(spies)](./js-utils.spylogger.md) | Create a spy logger using the provided methods, which returns itself as a child. |
+|  [spyLogger(spies)](./js-utils.spylogger.md) | Create a spy logger using the provided methods, which returns itself as a child. ensure all methods are present by extending null logger |
 |  [sum(a, b)](./js-utils.sum.md) | Add numbers. PredicateR2<!-- -->&lt;<!-- -->number, number<!-- -->&gt; |
-|  [timeout(ms, oper)](./js-utils.timeout.md) | Reject after a set amount of time if the original promise has not yet resolved. |
+|  [timeout(ms, inner)](./js-utils.timeout.md) | Reject after a set amount of time if the original promise has not yet resolved. |
 |  [toArray(val)](./js-utils.toarray.md) |  |
 |  [toArray(val)](./js-utils.toarray_1.md) |  |
 |  [trim(val, max, tail)](./js-utils.trim.md) |  |
-|  [waitFor(cb, step, count)](./js-utils.waitfor.md) | Reject after a set number of attempts if the given predicate does not return true. |
-|  [waitForChild(child)](./js-utils.waitforchild.md) | Wait for a child process to exit, collecting output, errors, and exit status. |
+|  [waitFor(cb, step, tries)](./js-utils.waitfor.md) |  |
+|  [waitForChild(child)](./js-utils.waitforchild.md) |  |
+|  [writeInput(stream, value)](./js-utils.writeinput.md) |  |
 |  [writeValue(stream, value)](./js-utils.writevalue.md) |  |
 
 ## Interfaces
@@ -96,7 +99,6 @@
 |  [ChildOptions](./js-utils.childoptions.md) |  |
 |  [ChildResult](./js-utils.childresult.md) |  |
 |  [Dict](./js-utils.dict.md) |  |
-|  [ExternalModule](./js-utils.externalmodule.md) |  |
 
 ## Variables
 
@@ -114,7 +116,6 @@
 |  [ChildSpawner](./js-utils.childspawner.md) |  |
 |  [MapLike](./js-utils.maplike.md) | A <code>Map</code> or dictionary object with string keys and <code>TVal</code> values. |
 |  [Maybe](./js-utils.maybe.md) | Value that may be nil. |
-|  [ModuleCtor](./js-utils.modulector.md) |  |
 |  [Nil](./js-utils.nil.md) | Old name for None. |
 |  [None](./js-utils.none.md) | Unset value. |
 |  [Optional](./js-utils.optional.md) | Old name for Maybe. |
diff --git a/docs/api/js-utils.modulector.md b/docs/api/js-utils.modulector.md
deleted file mode 100644
index a6d09d4..0000000
--- a/docs/api/js-utils.modulector.md
+++ /dev/null
@@ -1,11 +0,0 @@
-<!-- Do not edit this file. It is automatically generated by API Documenter. -->
-
-[Home](./index.md) &gt; [@apextoaster/js-utils](./js-utils.md) &gt; [ModuleCtor](./js-utils.modulector.md)
-
-## ModuleCtor type
-
-<b>Signature:</b>
-
-```typescript
-export declare type ModuleCtor = new (data: unknown) => Module;
-```
diff --git a/docs/api/js-utils.spylogger.md b/docs/api/js-utils.spylogger.md
index d4cc34f..9d85a41 100644
--- a/docs/api/js-utils.spylogger.md
+++ b/docs/api/js-utils.spylogger.md
@@ -6,6 +6,8 @@
 
 Create a spy logger using the provided methods, which returns itself as a child.
 
+ ensure all methods are present by extending null logger
+
 <b>Signature:</b>
 
 ```typescript
diff --git a/docs/api/js-utils.timeout.md b/docs/api/js-utils.timeout.md
index 8f2a00a..637f023 100644
--- a/docs/api/js-utils.timeout.md
+++ b/docs/api/js-utils.timeout.md
@@ -9,7 +9,7 @@ Reject after a set amount of time if the original promise has not yet resolved.
 <b>Signature:</b>
 
 ```typescript
-export declare function timeout<T>(ms: number, oper: Promise<T>): Promise<T>;
+export declare function timeout<T>(ms: number, inner: Promise<T>): Promise<T>;
 ```
 
 ## Parameters
@@ -17,7 +17,7 @@ export declare function timeout<T>(ms: number, oper: Promise<T>): Promise<T>;
 |  Parameter | Type | Description |
 |  --- | --- | --- |
 |  ms | number |  |
-|  oper | Promise&lt;T&gt; |  |
+|  inner | Promise&lt;T&gt; |  |
 
 <b>Returns:</b>
 
diff --git a/docs/api/js-utils.waitfor.md b/docs/api/js-utils.waitfor.md
index 94118e6..5414beb 100644
--- a/docs/api/js-utils.waitfor.md
+++ b/docs/api/js-utils.waitfor.md
@@ -4,12 +4,14 @@
 
 ## waitFor() function
 
-Reject after a set number of attempts if the given predicate does not return true.
+> Warning: This API is now obsolete.
+> 
+> 
 
 <b>Signature:</b>
 
 ```typescript
-export declare function waitFor(cb: PredicateC0, step: number, count: number): Promise<void>;
+export declare function waitFor(cb: PredicateC0, step: number, tries: number): Promise<void>;
 ```
 
 ## Parameters
@@ -18,13 +20,9 @@ export declare function waitFor(cb: PredicateC0, step: number, count: number): P
 |  --- | --- | --- |
 |  cb | PredicateC0 |  |
 |  step | number |  |
-|  count | number |  |
+|  tries | number |  |
 
 <b>Returns:</b>
 
 Promise&lt;void&gt;
 
-## Exceptions
-
-TimeoutError
-
diff --git a/docs/api/js-utils.waitforchild.md b/docs/api/js-utils.waitforchild.md
index 36c7888..fb964e5 100644
--- a/docs/api/js-utils.waitforchild.md
+++ b/docs/api/js-utils.waitforchild.md
@@ -4,7 +4,9 @@
 
 ## waitForChild() function
 
-Wait for a child process to exit, collecting output, errors, and exit status.
+> Warning: This API is now obsolete.
+> 
+> 
 
 <b>Signature:</b>
 
diff --git a/docs/api/js-utils.writeinput.md b/docs/api/js-utils.writeinput.md
new file mode 100644
index 0000000..f26808b
--- /dev/null
+++ b/docs/api/js-utils.writeinput.md
@@ -0,0 +1,23 @@
+<!-- Do not edit this file. It is automatically generated by API Documenter. -->
+
+[Home](./index.md) &gt; [@apextoaster/js-utils](./js-utils.md) &gt; [writeInput](./js-utils.writeinput.md)
+
+## writeInput() function
+
+<b>Signature:</b>
+
+```typescript
+export declare function writeInput(stream: Writable, value: string): Promise<boolean>;
+```
+
+## Parameters
+
+|  Parameter | Type | Description |
+|  --- | --- | --- |
+|  stream | Writable |  |
+|  value | string |  |
+
+<b>Returns:</b>
+
+Promise&lt;boolean&gt;
+
diff --git a/docs/api/js-utils.writevalue.md b/docs/api/js-utils.writevalue.md
index aac6844..ff3c466 100644
--- a/docs/api/js-utils.writevalue.md
+++ b/docs/api/js-utils.writevalue.md
@@ -4,6 +4,10 @@
 
 ## writeValue() function
 
+> Warning: This API is now obsolete.
+> 
+> 
+
 <b>Signature:</b>
 
 ```typescript
diff --git a/src/Async.ts b/src/Async.ts
index 7031e74..905e7d8 100644
--- a/src/Async.ts
+++ b/src/Async.ts
@@ -25,14 +25,14 @@ export function deferValue<T>(ms: number, val: T): Promise<T> {
  * Reject after a set amount of time if the original promise has not yet resolved.
  * @public
  */
-export function timeout<T>(ms: number, oper: Promise<T>): Promise<T> {
+export function timeout<T>(ms: number, inner: Promise<T>): Promise<T> {
   const limit = new Promise<T>((_res, rej) => {
     setTimeout(() => {
       rej(new TimeoutError());
     }, ms);
   });
 
-  return Promise.race([limit, oper]);
+  return Promise.race([limit, inner]);
 }
 
 /**
@@ -40,15 +40,23 @@ export function timeout<T>(ms: number, oper: Promise<T>): Promise<T> {
  * @public
  * @throws TimeoutError
  */
-export async function waitFor(cb: PredicateC0, step: number, count: number): Promise<void> {
-  let accum = 0;
-  while (accum < count) {
+export async function deferUntil(cb: PredicateC0, step: number, tries: number): Promise<void> {
+  let count = 0;
+  while (count < tries) {
     await defer(step);
     if (cb()) {
       return;
     }
-    accum += 1;
+    count += 1;
   }
 
   throw new TimeoutError();
 }
+
+/**
+ * @public
+ * @deprecated
+ */
+export async function waitFor(cb: PredicateC0, step: number, tries: number): Promise<void> {
+  return deferUntil(cb, step, tries);
+}
diff --git a/src/Child.ts b/src/Child.ts
index dfb6f5a..93e026b 100644
--- a/src/Child.ts
+++ b/src/Child.ts
@@ -37,7 +37,7 @@ const CHILD_OUTPUT = 'child process emitted error output';
  *
  * @public
  */
-export function waitForChild(child: ChildStreams): Promise<ChildResult> {
+export function childResult(child: ChildStreams): Promise<ChildResult> {
   return new Promise((res, rej) => {
     const stderr: Array<Buffer> = [];
     const stdout: Array<Buffer> = [];
@@ -78,7 +78,15 @@ export function waitForChild(child: ChildStreams): Promise<ChildResult> {
   });
 }
 
-export function writeValue(stream: Writable, value: string): Promise<boolean> {
+/**
+ * @public
+ * @deprecated
+ */
+export function waitForChild(child: ChildStreams): Promise<ChildResult> {
+  return childResult(child);
+}
+
+export function writeInput(stream: Writable, value: string): Promise<boolean> {
   return new Promise<boolean>((res, rej) => {
     stream.write(value, (err: Maybe<Error>) => {
       if (doesExist(err)) {
@@ -91,3 +99,11 @@ export function writeValue(stream: Writable, value: string): Promise<boolean> {
     });
   });
 }
+
+/**
+ * @public
+ * @deprecated
+ */
+export function writeValue(stream: Writable, value: string): Promise<boolean> {
+  return writeInput(stream, value);
+}
diff --git a/src/ExternalModule.ts b/src/ExternalModule.ts
deleted file mode 100644
index 0f2671c..0000000
--- a/src/ExternalModule.ts
+++ /dev/null
@@ -1,14 +0,0 @@
-import { Module } from 'noicejs';
-
-export interface ExternalModule {
-  data?: unknown;
-  export: string;
-  require: string;
-}
-
-export type ModuleCtor = new (data: unknown) => Module;
-
-export function isModule(it: object): it is ModuleCtor {
-  const p = Reflect.getPrototypeOf(it);
-  return p === Module || p instanceof Module;
-}
diff --git a/src/Logger.ts b/src/Logger.ts
index 60eabf5..2f3dfac 100644
--- a/src/Logger.ts
+++ b/src/Logger.ts
@@ -14,11 +14,14 @@ export function getTestLogger(verbose = false): Logger {
 
 /**
  * Create a spy logger using the provided methods, which returns itself as a child.
+ *
+ * @todo ensure all methods are present by extending null logger
  */
 export function spyLogger(spies: Partial<Logger>): Logger {
   const logger = {
     ...spies,
     child: () => logger,
   } as Logger;
+
   return logger;
 }
diff --git a/src/index.ts b/src/index.ts
index 7bad082..adf14a9 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -24,6 +24,7 @@ export {
   defer,
   deferValue,
   timeout,
+  deferUntil,
   waitFor,
 } from './Async';
 export {
@@ -40,16 +41,14 @@ export {
   ChildOptions,
   ChildResult,
   ChildSpawner,
+  childResult,
   waitForChild,
+  writeInput,
   writeValue,
 } from './Child';
 export {
   isDebug
 } from './Env';
-export {
-  ExternalModule,
-  ModuleCtor,
-} from './ExternalModule';
 export {
   getTestLogger,
   spyLogger,
diff --git a/test/utils/TestChild.ts b/test/utils/TestChild.ts
index 9867090..1e1bb62 100644
--- a/test/utils/TestChild.ts
+++ b/test/utils/TestChild.ts
@@ -1,7 +1,7 @@
 import { expect } from 'chai';
 
 import { ChildProcessError } from '../../src';
-import { ChildStreams, waitForChild } from '../../src/Child';
+import { ChildStreams, childResult } from '../../src/Child';
 import { Maybe, mustExist } from '../../src/Maybe';
 
 type Closer = (status: number) => Promise<void>;
@@ -33,7 +33,7 @@ describe('child process utils', async () => {
     it('should read stdout data', async () => {
       const child = createChild();
 
-      const resultPromise = waitForChild(child);
+      const resultPromise = childResult(child);
       await mustExist(child.closer)(0);
 
       const result = await resultPromise;
@@ -46,7 +46,7 @@ describe('child process utils', async () => {
     it('should reject on failure status', async () => {
       const child = createChild();
 
-      const resultPromise = waitForChild(child);
+      const resultPromise = childResult(child);
       await mustExist(child.closer)(1);
 
       return expect(resultPromise).to.eventually.be.rejectedWith(ChildProcessError);