Add tech stack

friends-reminder/tech-stack.md

@@ -0,0 +1,23 @@
+## Simple and boring
+
+### View: React + TypeScript + Redux (+ Redux Toolkit)
+
+- I'm very familiar with React
+- TypeScript saves a lot of debugging time
+- Redux + Redux Toolkit because it removes a lot of boilerplate and is easy to use
+
+### Logic: Firebase
+
+- already familiar with it
+- easier to setup than a custom express backend
+
+### Data: Firestore
+
+- already familiar with it
+- easy to connect to firebase
+
+## Tooling
+
+- VCS: Git/Github
+- CI: Github Actions
+- CD: Netlify