diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index f5ec1ed..5f7b0ac 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -109,5 +109,12 @@ jobs:
       - name: 'Install programming-challenges'
         run: 'npm install --global'
 
+      - uses: 'nrwl/last-successful-commit-action@v1'
+        id: 'last_successful_commit'
+        with:
+          branch: 'master'
+          workflow_id: 'ci.yml'
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+
       - name: 'Test'
-        run: 'programming-challenges run test --affected --ci'
+        run: 'programming-challenges run test --affected --ci --base=${{ steps.last_successful_commit.outputs.commit_hash }}'
diff --git a/cli/commands/run/test.ts b/cli/commands/run/test.ts
index e73337e..e6ed993 100644
--- a/cli/commands/run/test.ts
+++ b/cli/commands/run/test.ts
@@ -39,12 +39,17 @@ export class RunTestCommand extends Command {
     description: 'Run the tests for the Continuous Integration (CI).'
   })
 
+  public base = Option.String('--base', {
+    description: 'Base of the current branch (usually master)'
+  })
+
   async execute (): Promise<number> {
     console.log()
     try {
       if (this.affected) {
         const gitAffected = new GitAffected({
-          isContinuousIntegration: this.isContinuousIntegration
+          isContinuousIntegration: this.isContinuousIntegration,
+          base: this.base
         })
         const solutions = await gitAffected.getAffectedSolutions()
         for (const solution of solutions) {
diff --git a/cli/services/GitAffected.ts b/cli/services/GitAffected.ts
index 20d783a..cf03b93 100644
--- a/cli/services/GitAffected.ts
+++ b/cli/services/GitAffected.ts
@@ -9,13 +9,16 @@ const solutionsRegex = new RegExp(
 
 export interface GitAffectedOptions {
   isContinuousIntegration: boolean
+  base?: string
 }
 
 export class GitAffected implements GitAffectedOptions {
   public isContinuousIntegration: boolean
+  public base?: string
 
   constructor (options: GitAffectedOptions) {
     this.isContinuousIntegration = options.isContinuousIntegration
+    this.base = options.base
   }
 
   public parseGitOutput (output: string): string[] {
@@ -57,12 +60,14 @@ export class GitAffected implements GitAffectedOptions {
   }
 
   public async getAffectedSolutions (): Promise<Solution[]> {
-    const files = Array.from(
-      new Set([
-        ...(await this.getUnpushedFiles()),
-        ...(await this.getUncommittedFiles())
-      ])
-    )
+    let files = [
+      ...(await this.getUnpushedFiles()),
+      ...(await this.getUncommittedFiles())
+    ]
+    if (this.base != null) {
+      files.push(...(await this.getFilesUsingBaseAndHead(this.base, '.')))
+    }
+    files = Array.from(new Set(files))
     const affectedSolutionsPaths = files.filter((filePath) => {
       return solutionsRegex.test(filePath)
     })