diff --git a/packages/collector/__tests__/getProjectIssues.test.ts b/packages/collector/__tests__/getProjectIssues.test.ts
index ec58fad28..a0076161f 100644
--- a/packages/collector/__tests__/getProjectIssues.test.ts
+++ b/packages/collector/__tests__/getProjectIssues.test.ts
@@ -7,7 +7,9 @@ describe("Working issue listing", () => {
   beforeEach(() => {
     nock("https://api.github.com")
       .get("/repos/OWNER/REPO/issues")
-      .query((actualQueryObject) => actualQueryObject.labels === "help-wanted")
+      .query(
+        (actualQueryObject) => actualQueryObject["labels"] === "help-wanted",
+      )
       .reply(200, [
         {
           body: "BODY_C",
@@ -18,7 +20,9 @@ describe("Working issue listing", () => {
       ]);
     nock("https://api.github.com")
       .get("/repos/OWNER/REPO/issues")
-      .query((actualQueryObject) => actualQueryObject.labels === "help wanted")
+      .query(
+        (actualQueryObject) => actualQueryObject["labels"] === "help wanted",
+      )
       .reply(200, [
         {
           body: "BODY_I",
@@ -99,7 +103,7 @@ test("getProjectIssues auto-populates body", async () => {
 
   nock("https://api.github.com")
     .get("/repos/OWNER/REPO/issues")
-    .query((actualQueryObject) => actualQueryObject.labels === "help-wanted")
+    .query((actualQueryObject) => actualQueryObject["labels"] === "help-wanted")
     .reply(200, [
       { html_url: "https://example.test", number: 1, title: "CORRECT" },
     ]);
diff --git a/packages/collector/__tests__/setup.ts b/packages/collector/__tests__/setup.ts
index 7af8df483..028fc8219 100644
--- a/packages/collector/__tests__/setup.ts
+++ b/packages/collector/__tests__/setup.ts
@@ -10,7 +10,7 @@ jest.mock("../src/octokit", () => {
   const OctokitWithRest = Octokit.plugin(restEndpointMethods);
   return {
     octokit: new OctokitWithRest({
-      auth: process.env.PAT,
+      auth: process.env["PAT"],
       request: {
         fetch: nodeFetch,
       },
diff --git a/packages/collector/eslint.config.js b/packages/collector/eslint.config.js
index 06b5c693f..af61d636a 100644
--- a/packages/collector/eslint.config.js
+++ b/packages/collector/eslint.config.js
@@ -207,6 +207,7 @@ export default tseslint.config(
     files: ["**/*.js"],
     rules: {
       "@typescript-eslint/no-unsafe-argument": "off",
+      "@typescript-eslint/no-unsafe-assignment": "off",
     },
   },
 );
diff --git a/packages/collector/src/getProjectIssues.ts b/packages/collector/src/getProjectIssues.ts
index 581e3da14..668df4272 100644
--- a/packages/collector/src/getProjectIssues.ts
+++ b/packages/collector/src/getProjectIssues.ts
@@ -22,7 +22,7 @@ export async function getProjectIssues(
     });
   return issues.data.map((issue) => ({
     description: issue.body ?? "",
-    link: publicRepo ? issue.html_url : undefined,
+    ...(publicRepo && { link: issue.html_url }),
     number: issue.number,
     title: issue.title,
   }));
diff --git a/packages/collector/src/octokit.ts b/packages/collector/src/octokit.ts
index cab269f88..d1601a788 100644
--- a/packages/collector/src/octokit.ts
+++ b/packages/collector/src/octokit.ts
@@ -3,4 +3,4 @@ import { restEndpointMethods } from "@octokit/plugin-rest-endpoint-methods";
 
 // eslint-disable-next-line @typescript-eslint/naming-convention -- Classes should be PascalCase
 const OctokitWithRest = Octokit.plugin(restEndpointMethods);
-export const octokit = new OctokitWithRest({ auth: process.env.PAT });
+export const octokit = new OctokitWithRest({ auth: process.env["PAT"] });
diff --git a/packages/collector/tsconfig.json b/packages/collector/tsconfig.json
index 371325d13..803f6eaa4 100644
--- a/packages/collector/tsconfig.json
+++ b/packages/collector/tsconfig.json
@@ -2,8 +2,14 @@
   "compilerOptions": {
     "esModuleInterop": true,
     "forceConsistentCasingInFileNames": true,
+
+    "allowUnreachableCode": false,
+    "allowUnusedLabels": false,
+    "exactOptionalPropertyTypes": true,
     "noFallthroughCasesInSwitch": true,
+    "noImplicitOverride": true,
     "noImplicitReturns": true,
+    "noPropertyAccessFromIndexSignature": true,
     "noUnusedLocals": true,
     "noUnusedParameters": true,
     "strict": true
diff --git a/packages/frontend/__tests__/components/IssuesList.test.tsx b/packages/frontend/__tests__/components/IssuesList.test.tsx
index bf1f074f0..9056a1693 100644
--- a/packages/frontend/__tests__/components/IssuesList.test.tsx
+++ b/packages/frontend/__tests__/components/IssuesList.test.tsx
@@ -20,8 +20,9 @@ describe("IssuesList component", () => {
       <MemoryRouter>
         <IssuesList
           issues={project.issues.map((issue) => ({
-            ...issue,
-            link: undefined,
+            description: issue.description,
+            number: issue.number,
+            title: issue.title,
           }))}
           project={project}
         />
diff --git a/packages/frontend/src/components/Issue.tsx b/packages/frontend/src/components/Issue.tsx
index e439458ad..a9509dd4f 100644
--- a/packages/frontend/src/components/Issue.tsx
+++ b/packages/frontend/src/components/Issue.tsx
@@ -19,7 +19,7 @@ export const Issue = ({
     subtitle={issue.project.name}
     subtitleDescription={issue.project["short-description"]}
     subtitleLink={getProjectLink(issue.project)}
-    tags={!hideTags ? issue.project.tags : []}
+    tags={!hideTags ? issue.project.tags ?? [] : []}
     title={issue.title}
   />
 );
diff --git a/packages/frontend/src/components/Project.tsx b/packages/frontend/src/components/Project.tsx
index 62c6279b4..8293ce897 100644
--- a/packages/frontend/src/components/Project.tsx
+++ b/packages/frontend/src/components/Project.tsx
@@ -13,7 +13,7 @@ export const Project = ({
   <ArticleBox
     description={project.info.description}
     link={getProjectLink(project)}
-    tags={project.info.tags}
+    tags={project.info.tags ?? []}
     title={project.info.name}
   />
 );
diff --git a/packages/frontend/src/pages/IssueDetail.tsx b/packages/frontend/src/pages/IssueDetail.tsx
index 319819fec..d401ed4b0 100644
--- a/packages/frontend/src/pages/IssueDetail.tsx
+++ b/packages/frontend/src/pages/IssueDetail.tsx
@@ -47,8 +47,8 @@ export const IssueDetail = ({
   );
   const projectIssues = getIssuesWithProjectInfo(data, {
     omitIssueNumber: issue?.number,
-    owner: projectOwner,
-    repo: projectRepo,
+    ...(projectOwner !== undefined && { owner: projectOwner }),
+    ...(projectRepo !== undefined && { repo: projectRepo }),
   });
 
   if (!issue) {
diff --git a/packages/frontend/src/utils/getAllIssues.ts b/packages/frontend/src/utils/getAllIssues.ts
index 2fe0bee37..79c11280f 100644
--- a/packages/frontend/src/utils/getAllIssues.ts
+++ b/packages/frontend/src/utils/getAllIssues.ts
@@ -8,7 +8,7 @@ export interface ProjectIssueWithProjectInfo extends ProjectIssue {
 }
 
 interface Query extends Partial<Project> {
-  omitIssueNumber?: number;
+  omitIssueNumber: number | undefined;
 }
 
 export const getIssuesWithProjectInfo = (
diff --git a/packages/frontend/tsconfig.json b/packages/frontend/tsconfig.json
index cf3f657df..7aad91d9d 100644
--- a/packages/frontend/tsconfig.json
+++ b/packages/frontend/tsconfig.json
@@ -1,17 +1,23 @@
 {
   "compilerOptions": {
-    "module": "es2020",
-    "moduleResolution": "node",
     "allowSyntheticDefaultImports": true,
     "esModuleInterop": true,
-    "target": "es5",
-    "jsx": "react-jsx",
     "forceConsistentCasingInFileNames": true,
+    "jsx": "react-jsx",
+    "module": "es2020",
+    "moduleResolution": "node",
+    "sourceMap": true,
+    "target": "es5",
+
+    "allowUnreachableCode": false,
+    "allowUnusedLabels": false,
+    "exactOptionalPropertyTypes": true,
     "noFallthroughCasesInSwitch": true,
+    "noImplicitOverride": true,
     "noImplicitReturns": true,
+    "noPropertyAccessFromIndexSignature": true,
     "noUnusedLocals": true,
     "noUnusedParameters": true,
-    "sourceMap": true,
     "strict": true
   }
 }