diff --git a/src/action/base.ts b/src/action/base.ts
index 4fd77f2f..9efbf7a1 100644
--- a/src/action/base.ts
+++ b/src/action/base.ts
@@ -182,6 +182,6 @@ export class ActionBase {
    * write to the real stdout/stderr
    */
   protected _write(std: 'stdout' | 'stderr', s: string | string[]) {
-    this.stdmockOrigs[std].apply(process[std], _.castArray(s))
+    this.stdmockOrigs[std].apply(process[std], _.castArray(s) as [string])
   }
 }
diff --git a/src/action/spinner.ts b/src/action/spinner.ts
index 91e772ae..7c3896a1 100644
--- a/src/action/spinner.ts
+++ b/src/action/spinner.ts
@@ -31,8 +31,8 @@ export default class SpinnerAction extends ActionBase {
     this._reset()
     if (this.spinner) clearInterval(this.spinner)
     this._render()
-    let interval: any = (this.spinner = setInterval(
-      this._render.bind(this),
+    let interval: any = (this.spinner = setInterval(icon =>
+      this._render.bind(this)(icon),
       process.platform === 'win32' ? 500 : 100,
       'spinner',
     ))
diff --git a/src/deps.ts b/src/deps.ts
index bfe24a5f..d201c5e7 100644
--- a/src/deps.ts
+++ b/src/deps.ts
@@ -1,18 +1,18 @@
 export const deps = {
-  get stripAnsi(): typeof import ('strip-ansi') { return fetch('strip-ansi') },
-  get ansiStyles(): typeof import ('ansi-styles') { return fetch('ansi-styles') },
+  get stripAnsi(): (string: string) => string { return fetch('strip-ansi') },
+  get ansiStyles(): typeof import('ansi-styles') { return fetch('ansi-styles') },
   get ansiEscapes(): any { return fetch('ansi-escapes') },
   get passwordPrompt(): any { return fetch('password-prompt') },
-  get screen(): typeof import ('@oclif/screen') { return fetch('@oclif/screen') },
+  get screen(): typeof import('@oclif/screen') { return fetch('@oclif/screen') },
 
-  get open(): typeof import ('./open').default { return fetch('./open').default },
-  get prompt(): typeof import ('./prompt') { return fetch('./prompt') },
-  get styledObject(): typeof import ('./styled/object').default { return fetch('./styled/object').default },
-  get styledHeader(): typeof import ('./styled/header').default { return fetch('./styled/header').default },
-  get styledJSON(): typeof import ('./styled/json').default { return fetch('./styled/json').default },
-  get table(): typeof import ('./styled/table').table { return fetch('./styled/table').table },
-  get tree(): typeof import ('./styled/tree').default { return fetch('./styled/tree').default },
-  get wait(): typeof import ('./wait').default { return fetch('./wait').default },
+  get open(): typeof import('./open').default { return fetch('./open').default },
+  get prompt(): typeof import('./prompt') { return fetch('./prompt') },
+  get styledObject(): typeof import('./styled/object').default { return fetch('./styled/object').default },
+  get styledHeader(): typeof import('./styled/header').default { return fetch('./styled/header').default },
+  get styledJSON(): typeof import('./styled/json').default { return fetch('./styled/json').default },
+  get table(): typeof import('./styled/table').table { return fetch('./styled/table').table },
+  get tree(): typeof import('./styled/tree').default { return fetch('./styled/tree').default },
+  get wait(): typeof import('./wait').default { return fetch('./wait').default },
 }
 
 const cache: any = {}