diff --git a/.github/actions/toolchain-cargo-cached/action.yml b/.github/actions/toolchain-cargo-cached/action.yml
index ec175954..ea57be66 100644
--- a/.github/actions/toolchain-cargo-cached/action.yml
+++ b/.github/actions/toolchain-cargo-cached/action.yml
@@ -26,7 +26,7 @@ runs:
   using: 'composite'
   steps:
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - id: toolchain-cache-key
       run: |
diff --git a/.github/file-filters.yaml b/.github/file-filters.yaml
new file mode 100644
index 00000000..80430239
--- /dev/null
+++ b/.github/file-filters.yaml
@@ -0,0 +1,72 @@
+# This is used by the action https://github.com/dorny/paths-filter
+
+# Changes to actions/workflows that can affect any of our project components.
+action_changes: &action_changes
+  - '.github/actions/**/action.yaml'
+  - '.github/workflows/ci.yaml'
+  - '.github/file-filters.yaml'
+
+# Frontend
+frontend_dependencies: &frontend_dependencies
+  - 'frontend/{package,now,vercel}.json'
+  - 'frontend/package-lock.json'
+
+eslint_config: &eslint_config
+  - 'frontend/.eslint*'
+
+frontend_workflow: &frontend_workflow
+  - '.github/workflows/frontend.yaml'
+
+frontend: &frontend
+  - *action_changes
+  - *frontend_dependencies
+  - *frontend_workflow
+  - *eslint_config
+  - 'frontend/**/*.[tj]{s,sx}'
+  - 'frontend/**/tsconfig*.json'
+
+proto: &proto
+  - 'proto/*.proto'
+
+# Agency
+agency_dependencies: &agency_dependencies
+  - 'agency/pyproject.toml'
+  - 'agency/poetry.lock'
+  - 'agency/.python-version'
+
+agency_workflow: &agency_workflow
+  - '.github/workflows/agency.yaml'
+
+agency: &agency
+  - *action_changes
+  - *agency_dependencies
+  - *agency_workflow
+  - *proto
+  - 'agency/app/**/*.py'
+
+# Server
+server_dependencies: &server_dependencies
+  - 'Cargo.toml'
+  - 'Cargo.lock'
+  - 'rust-toolchain.toml'
+
+server_workflow: &server_workflow
+  - '.github/workflows/server.yaml'
+
+server_migrations: &server_migrations
+  - 'server/migrations/**.sql'
+
+sqlx_query_cache: &sqlx_query_cache
+  - 'server/.sqlx/**.json'
+
+server_config: &server_config
+  - 'server/config/**.toml'
+
+server: &server
+  - *action_changes
+  - *server_dependencies
+  - *server_workflow
+  - *server_migrations
+  - *sqlx_query_cache
+  - *proto
+  - 'server/src/**/*.rs'
\ No newline at end of file
diff --git a/.github/workflows/python.yaml b/.github/workflows/agency.yaml
similarity index 94%
rename from .github/workflows/python.yaml
rename to .github/workflows/agency.yaml
index 86a8db49..ae29f05f 100644
--- a/.github/workflows/python.yaml
+++ b/.github/workflows/agency.yaml
@@ -1,7 +1,6 @@
-name: Python CI
-
+name: Agency CI
 on:
-  push:
+  workflow_call:
 
 defaults:
   run:
diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
new file mode 100644
index 00000000..0b600d01
--- /dev/null
+++ b/.github/workflows/ci.yaml
@@ -0,0 +1,43 @@
+name: CI
+
+on: push
+
+env:
+  CARGO_TERM_COLOR: always
+  CARGO_INCREMENTAL: 0
+  CARGO_NET_RETRY: 10
+  RUST_BACKTRACE: short
+  RUSTFLAGS: "-D warnings"
+  RUSTUP_MAX_RETRIES: 10
+
+jobs:
+  detect-changes:
+    name: Detect which files have changed
+    runs-on: ubuntu-latest
+    timeout-minutes: 3
+    # Map a step output to a job output
+    outputs:
+      agency: ${{ steps.changes.outputs.agency }}
+      frontend: ${{ steps.changes.outputs.frontend }}
+      llmlingua_service: ${{ steps.changes.outputs.llmlingua_service }}
+      proto: ${{ steps.changes.outputs.proto }}
+      server: ${{ steps.changes.outputs.server }}
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Find changes
+        uses: dorny/paths-filter@de90cc6fb38fc0963ad72b210f1f284cd68cea36
+        id: changes
+        with:
+          token: ${{ github.token }}
+          filters: .github/file-filters.yaml
+
+  agency:
+    if: needs.detect-changes.outputs.agency == 'true'
+    needs: detect-changes
+    uses: ./.github/workflows/agency.yaml
+
+  server:
+    if: needs.detect-changes.outputs.server == 'true'
+    needs: detect-changes
+    uses: ./.github/workflows/server.yaml
\ No newline at end of file
diff --git a/.github/workflows/rust.yaml b/.github/workflows/rust.yaml
deleted file mode 100644
index 79fd6ce2..00000000
--- a/.github/workflows/rust.yaml
+++ /dev/null
@@ -1,41 +0,0 @@
-name: Rust CI
-
-on: push
-
-defaults:
-  run:
-    working-directory: server
-
-env:
-  CARGO_TERM_COLOR: always
-  CARGO_INCREMENTAL: 0
-  CARGO_NET_RETRY: 10
-  RUST_BACKTRACE: short
-  RUSTFLAGS: "-D warnings"
-  RUSTUP_MAX_RETRIES: 10
-
-jobs:
-  coverage-and-linting:
-    name: Test coverage & linting
-    runs-on: ubuntu-latest
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v4
-
-      - name: Install Protoc
-        uses: arduino/setup-protoc@v3
-
-      - name: Setup Rust Toolchain
-        uses: ./.github/actions/toolchain-cargo-cached
-        with:
-          components: llvm-tools-preview, rustfmt, clippy
-          crates: cargo-llvm-cov
-
-      - name: Tests & coverage
-        run: cargo llvm-cov test --no-fail-fast --workspace
-
-      - name: Linting rustfmt
-        run: cargo fmt --all -- --check
-
-      - name: Linting clippy
-        run: cargo clippy --
\ No newline at end of file
diff --git a/.github/workflows/server.yaml b/.github/workflows/server.yaml
new file mode 100644
index 00000000..05c3980c
--- /dev/null
+++ b/.github/workflows/server.yaml
@@ -0,0 +1,75 @@
+name: Rust Server CI
+on:
+  workflow_call:
+
+defaults:
+  run:
+    working-directory: server
+
+env:
+  CARGO_TERM_COLOR: always
+  CARGO_INCREMENTAL: 0
+  CARGO_NET_RETRY: 10
+  RUST_BACKTRACE: short
+  RUSTFLAGS: "-D warnings"
+  RUSTUP_MAX_RETRIES: 10
+
+jobs:
+  detect-changes:
+    name: Detect which files have changed
+    runs-on: ubuntu-latest
+    timeout-minutes: 3
+    # Map a step output to a job output
+    outputs:
+      agency: ${{ steps.changes.outputs.agency }}
+      frontend: ${{ steps.changes.outputs.frontend }}
+      llmlingua_service: ${{ steps.changes.outputs.llmlingua_service }}
+      proto: ${{ steps.changes.outputs.proto }}
+      server: ${{ steps.changes.outputs.server }}
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Find changes
+        uses: dorny/paths-filter@de90cc6fb38fc0963ad72b210f1f284cd68cea36  # v2
+        id: changes
+        with:
+          token: ${{ github.token }}
+          filters: .github/file-filters.yml
+
+  coverage-and-linting:
+    name: Test coverage & linting
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - uses: dorny/paths-filter@v3
+        id: changes
+        with:
+          filters: |
+            src:
+              - 'src/**'
+
+        # run only if some file in 'src' folder was changed
+      - if: steps.changes.outputs.src == 'true'
+        run: ...
+
+      - name: Install Protoc
+        uses: arduino/setup-protoc@v3
+        with:
+          repo-token: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Setup Rust Toolchain
+        uses: ./.github/actions/toolchain-cargo-cached
+        with:
+          components: llvm-tools-preview, rustfmt, clippy
+          crates: cargo-llvm-cov
+
+      - name: Tests & coverage
+        run: cargo llvm-cov test --no-fail-fast --workspace
+
+      - name: Linting rustfmt
+        run: cargo fmt --all -- --check
+
+      - name: Linting clippy
+        run: cargo clippy --
\ No newline at end of file