mobile navigation

media queries

.gitignore

@@ -21,7 +21,7 @@ node_modules/
 *.key
 
 # Go build artifacts
-backend-go/bin/
+backend/bin/
 *.exe
 *.exe~
 *.dll

.prettierignore

@@ -1,7 +1,7 @@
 node_modules/
 frontend/dist/
 frontend/build/
-backend-go/bin/
+backend/bin/
 *.lock
 Prompts/
 .claude/

Makefile

@@ -2,7 +2,7 @@
         test-go test-js lint-go lint-js fmt-go fmt-js fmt-check-go fmt-check-js \
         build-go build-js
 
-GODIR    := backend-go
+GODIR    := backend
 JSDIR    := frontend
 PRETTIER := $(JSDIR)/node_modules/.bin/prettier
 

README.md

@@ -28,8 +28,8 @@ make hooks
 cd frontend && npm install && cd ..
 
 # Copy and fill in environment variables
-cp backend-go/.env.example backend-go/.env
+cp backend/.env.example backend/.env
-# edit backend-go/.env with your DATABASE_URL, FIREBASE_PROJECT_ID, ETH_RPC_URL
+# edit backend/.env with your DATABASE_URL, FIREBASE_PROJECT_ID, ETH_RPC_URL
 
 # Run checks (requires golangci-lint)
 make check
@@ -38,7 +38,7 @@ make check
 make run
 
 # Start the poller (separate terminal)
-cd backend-go && go run ./cmd/poller
+cd backend && go run ./cmd/poller
 
 # Start the frontend dev server (separate terminal)
 cd frontend && npm run dev
@@ -63,7 +63,7 @@ frontend:
 
 ```
 koin_ping_0.2.0/
-├── backend-go/                # Go monorepo root
+├── backend/                # Go monorepo root
 │   ├── cmd/api/               # HTTP REST API server
 │   ├── cmd/poller/            # Blockchain polling daemon
 │   └── internal/

REPO_POLICIES.md

@@ -6,12 +6,12 @@ last_modified: 2026-02-22
 This document covers repository structure, tooling, and workflow standards. Code
 style conventions are in separate documents:
 
-- [Code Styleguide](https://git.eeqj.de/sneak/prompts/raw/branch/main/prompts/CODE_STYLEGUIDE.md)
+- [Code Styleguide](<link>)
   (general, bash, Docker)
-- [Go](https://git.eeqj.de/sneak/prompts/raw/branch/main/prompts/CODE_STYLEGUIDE_GO.md)
+- [Go](<link>)
-- [JavaScript](https://git.eeqj.de/sneak/prompts/raw/branch/main/prompts/CODE_STYLEGUIDE_JS.md)
+- [JavaScript](<link>)
-- [Python](https://git.eeqj.de/sneak/prompts/raw/branch/main/prompts/CODE_STYLEGUIDE_PYTHON.md)
+- [Python](<link>)
-- [Go HTTP Server Conventions](https://git.eeqj.de/sneak/prompts/raw/branch/main/prompts/GO_HTTP_SERVER_CONVENTIONS.md)
+- [Go HTTP Server Conventions](<link>)
 
 ---
 
@@ -37,7 +37,7 @@ style conventions are in separate documents:
   `make test`, `make lint`, `make fmt` (writes), `make fmt-check` (read-only),
   `make check` (prereqs: `test`, `lint`, `fmt-check`), `make docker`, and
   `make hooks` (installs pre-commit hook). A model Makefile is at
-  `https://git.eeqj.de/sneak/prompts/raw/branch/main/Makefile`.
+  `(<link>)`.
 
 - Always use Makefile targets (`make fmt`, `make test`, `make lint`, etc.)
   instead of invoking the underlying tools directly. The Makefile is the single
@@ -95,7 +95,7 @@ style conventions are in separate documents:
 - `.gitignore` should be comprehensive from the start: OS files (`.DS_Store`),
   editor files (`.swp`, `*~`), language build artifacts, and `node_modules/`.
   Fetch the standard `.gitignore` from
-  `https://git.eeqj.de/sneak/prompts/raw/branch/main/.gitignore` when setting up
+  `(<link>) when setting up
   a new repo.
 
 - Never use `git add -A` or `git add .`. Always stage files explicitly by name.
@@ -107,7 +107,7 @@ style conventions are in separate documents:
 
 - `.golangci.yml` is standardized and must _NEVER_ be modified by an agent, only
   manually by the user. Fetch from
-  `https://git.eeqj.de/sneak/prompts/raw/branch/main/.golangci.yml`.
+  `(<link>)`.
 
 - When pinning images or packages by hash, add a comment above the reference
   with the version and date (YYYY-MM-DD).
@@ -124,7 +124,7 @@ style conventions are in separate documents:
 - `README.md` is the primary documentation. Required sections:
     - **Description**: First line must include the project name, purpose,
       category (web server, SPA, CLI tool, etc.), license, and author. Example:
-      "µPaaS is an MIT-licensed Go web application by @sneak that receives
+      "µPaaS is an MIT-licensed Go web application by @sjdev that receives
       git-frontend webhooks and deploys applications via Docker in realtime."
     - **Getting Started**: Copy-pasteable install/usage code block.
     - **Rationale**: Why does this exist?
@@ -134,12 +134,11 @@ style conventions are in separate documents:
       left off.
     - **License**: MIT, GPL, or WTFPL. Ask the user for new projects. Include a
       `LICENSE` file in the repo root and a License section in the README.
-    - **Author**: [@sneak](https://sneak.berlin).
+    - **Author**: [@sjdev](https://sjdev.co).
 
 - First commit of a new repo should contain only `README.md`.
 
-- Go module root: `sneak.berlin/go/<name>`. Always run `go mod tidy` before
+- Always run `go mod tidy` before committing.
-  committing.
 
 - Use SemVer.
 
@@ -175,7 +174,7 @@ style conventions are in separate documents:
 
 - When setting up a new repo, files from the `prompts` repo may be used as
   templates. Fetch them from
-  `https://git.eeqj.de/sneak/prompts/raw/branch/main/<path>`.
+  `(<link>)<path>`.
 
 - New repos must contain at minimum:
     - `README.md`, `.git`, `.gitignore`, `.editorconfig`

backend-go/.env.example

@@ -1,20 +0,0 @@
-# Server
-PORT=3001
-API_BASE_PATH=/v1
-NODE_ENV=development
-
-# Database
-DATABASE_URL=postgresql://user:password@localhost:5432/koin_ping
-
-# Ethereum JSON-RPC
-ETH_RPC_URL=https://mainnet.infura.io/v3/YOUR-PROJECT-ID
-
-# Polling interval (ms, minimum 1000)
-POLL_INTERVAL_MS=60000
-
-# Firebase
-FIREBASE_PROJECT_ID=koin-ping
-
-# Email notifications (Resend — https://resend.com)
-# RESEND_API_KEY=re_xxxxxxxxxxxx
-# EMAIL_FROM=Koin Ping <alerts@yourdomain.com>

backend-go/internal/notifications/notifier.go

@@ -1,16 +0,0 @@
-package notifications
-
-import "context"
-
-// AlertMetadata holds context about the alert being sent.
-type AlertMetadata struct {
-	TxHash       string
-	AddressLabel string
-	AlertType    string
-	Address      string
-}
-
-// Notifier is the interface implemented by all notification channels.
-type Notifier interface {
-	Send(ctx context.Context, message string, meta AlertMetadata) error
-}

backend/README.md

@@ -2,16 +2,16 @@ Start DB:
 
 brew services start postgresql@15
 
-From the backend-go directory, you have a few options:
+From the backend directory, you have a few options:
 
 Option 1: Single command (both API + poller)
-cd /Users/kjannette/workspace/koin_ping_0.2.0/backend-gomake dev-all
+cd /Users/kjannette/workspace/koin_ping_0.2.0/backendmake dev-all
 
 Option 2: Two separate terminals
 Terminal 1 (API server):
-cd /Users/kjannette/workspace/koin_ping_0.2.0/backend-go go run ./cmd/api
+cd /Users/kjannette/workspace/koin_ping_0.2.0/backend go run ./cmd/api
 Terminal 2 (Poller):
-cd /Users/kjannette/workspace/koin_ping_0.2.0/backend-go go run ./cmd/poller
+cd /Users/kjannette/workspace/koin_ping_0.2.0/backend go run ./cmd/poller
 
 make run — Builds and runs the API server.
 make dev — Runs the API server with auto-reload via air (falls back to go run if air isn't installed).

backend/cmd/api/main.go

@@ -8,13 +8,13 @@ import (
 	"time"
 
 	"github.com/joho/godotenv"
-	"github.com/kjannette/koin-ping/backend-go/internal/config"
+	"github.com/kjannette/koin-ping/backend/internal/config"
-	"github.com/kjannette/koin-ping/backend-go/internal/database"
+	"github.com/kjannette/koin-ping/backend/internal/database"
-	"github.com/kjannette/koin-ping/backend-go/internal/firebase"
+	"github.com/kjannette/koin-ping/backend/internal/firebase"
-	"github.com/kjannette/koin-ping/backend-go/internal/handlers"
+	"github.com/kjannette/koin-ping/backend/internal/handlers"
-	"github.com/kjannette/koin-ping/backend-go/internal/middleware"
+	"github.com/kjannette/koin-ping/backend/internal/middleware"
-	"github.com/kjannette/koin-ping/backend-go/internal/models"
+	"github.com/kjannette/koin-ping/backend/internal/models"
-	"github.com/kjannette/koin-ping/backend-go/internal/services"
+	"github.com/kjannette/koin-ping/backend/internal/services"
 )
 
 const (
@@ -62,6 +62,7 @@ func main() {
 	emailDigestHandler := handlers.NewEmailDigestHandler(emailDigestSvc, notifConfigModel)
 	statusHandler := handlers.NewStatusHandler(checkpointModel)
 	stripeHandler := handlers.NewStripeHandler(userModel, cfg)
+	accountHandler := handlers.NewAccountHandler(userModel, cfg)
 
 	authenticate := middleware.Authenticate(userModel)
 	requireSub := middleware.RequireSubscription(userModel)
@@ -88,6 +89,12 @@ func main() {
 		authenticate(http.HandlerFunc(stripeHandler.GetSubscriptionStatus)))
 	mux.Handle("POST "+b+"/stripe/verify-checkout",
 		authenticate(http.HandlerFunc(stripeHandler.VerifyCheckoutSession)))
+	mux.Handle("POST "+b+"/stripe/create-portal-session",
+		authenticate(http.HandlerFunc(stripeHandler.CreatePortalSession)))
+
+	// Account route (auth required, NO subscription required)
+	mux.Handle("GET "+b+"/user/account",
+		authenticate(http.HandlerFunc(accountHandler.GetAccount)))
 
 	// Authenticated + subscribed routes — addresses
 	mux.Handle("POST "+b+"/addresses",

backend/cmd/poller/main.go

@@ -12,11 +12,11 @@ import (
 	"time"
 
 	"github.com/joho/godotenv"
-	"github.com/kjannette/koin-ping/backend-go/internal/config"
+	"github.com/kjannette/koin-ping/backend/internal/config"
-	"github.com/kjannette/koin-ping/backend-go/internal/database"
+	"github.com/kjannette/koin-ping/backend/internal/database"
-	"github.com/kjannette/koin-ping/backend-go/internal/models"
+	"github.com/kjannette/koin-ping/backend/internal/models"
-	"github.com/kjannette/koin-ping/backend-go/internal/protocols/ethereum"
+	"github.com/kjannette/koin-ping/backend/internal/protocols/ethereum"
-	"github.com/kjannette/koin-ping/backend-go/internal/services"
+	"github.com/kjannette/koin-ping/backend/internal/services"
 )
 
 const (
@@ -138,6 +138,8 @@ func runCycle(
 		return
 	}
 
+	evaluator.WaitForNotifications()
+
 	duration := time.Since(startTime)
 	log.Printf("[%s] Cycle complete: %d observations, %d alerts fired in %s",
 		time.Now().UTC().Format(time.RFC3339),

backend/go.mod

@@ -1,4 +1,4 @@
-module github.com/kjannette/koin-ping/backend-go
+module github.com/kjannette/koin-ping/backend
 
 go 1.25.0
 

backend/internal/domain/types.go

@@ -47,7 +47,7 @@ var ThresholdRequiredTypes = []AlertType{ //nolint:gochecknoglobals
 	AlertBalanceBelow,
 }
 
-// IsValidAlertType returns true if the given string matches a known AlertType.
+// returns true if the given string matches a known AlertType.
 func IsValidAlertType(t string) bool {
 	for _, v := range ValidAlertTypes {
 		if string(v) == t {
@@ -58,7 +58,6 @@ func IsValidAlertType(t string) bool {
 	return false
 }
 
-// IsThresholdRequired returns true if the given AlertType requires a threshold.
 func IsThresholdRequired(t AlertType) bool {
 	for _, v := range ThresholdRequiredTypes {
 		if v == t {
@@ -93,7 +92,6 @@ type AddressCheckpoint struct {
 	LastCheckedAt    time.Time `json:"last_checked_at"`    //nolint:tagliatelle
 }
 
-// CheckpointDetail combines checkpoint and address info for reporting.
 type CheckpointDetail struct {
 	AddressID        int       `json:"address_id"`         //nolint:tagliatelle
 	Address          string    `json:"address"`
@@ -102,7 +100,7 @@ type CheckpointDetail struct {
 	LastCheckedAt    time.Time `json:"last_checked_at"`    //nolint:tagliatelle
 }
 
-// NotificationConfig holds a user's notification preferences.
+//  holds a user's notification preferences.
 type NotificationConfig struct {
 	UserID              string     `json:"user_id"`              //nolint:tagliatelle
 	DiscordWebhookURL   *string    `json:"discord_webhook_url"`  //nolint:tagliatelle
@@ -131,14 +129,12 @@ type NormalizedTx struct {
 	TokenValue    *string `json:"token_value,omitempty"`    //nolint:tagliatelle
 }
 
-// IsTokenTransfer returns true if this transaction represents an ERC-20 token transfer.
 func (tx NormalizedTx) IsTokenTransfer() bool {
 	return tx.TokenContract != nil
 }
 
 type Direction string
 
-// String implements fmt.Stringer.
 func (d Direction) String() string { return string(d) }
 
 const (

backend/internal/handlers/account.go

@@ -0,0 +1,66 @@
+package handlers
+
+import (
+	"log"
+	"net/http"
+	"time"
+
+	"github.com/kjannette/koin-ping/backend/internal/config"
+	"github.com/kjannette/koin-ping/backend/internal/middleware"
+	"github.com/kjannette/koin-ping/backend/internal/models"
+)
+
+type AccountHandler struct {
+	users *models.UserModel
+	cfg   *config.Config
+}
+
+func NewAccountHandler(users *models.UserModel, cfg *config.Config) *AccountHandler {
+	return &AccountHandler{users: users, cfg: cfg}
+}
+
+type accountResponse struct {
+	UserID             string  `json:"user_id"`
+	Email              string  `json:"email"`
+	UserName           string  `json:"user_name"`
+	SubscriptionStatus string  `json:"subscription_status"`
+	SubscriptionPlan   string  `json:"subscription_plan"`
+	MemberSince        *string `json:"member_since,omitempty"`
+	NextBillingDate    *string `json:"next_billing_date,omitempty"`
+	CancelAtPeriodEnd  bool    `json:"cancel_at_period_end"`
+	PeriodEndDate      *string `json:"period_end_date,omitempty"`
+}
+
+func (h *AccountHandler) GetAccount(w http.ResponseWriter, r *http.Request) {
+	userID := middleware.GetUserID(r.Context())
+	email := middleware.GetUserEmail(r.Context())
+
+	user, err := h.users.GetByID(r.Context(), userID)
+	if err != nil || user == nil {
+		log.Printf("Account: failed to get user %s: %v", userID, err)
+		writeError(w, http.StatusInternalServerError, "INTERNAL_ERROR", "Failed to load user")
+		return
+	}
+
+	resp := accountResponse{
+		UserID:             user.ID,
+		Email:              email,
+		UserName:           email,
+		SubscriptionStatus: user.SubscriptionStatus,
+		SubscriptionPlan:   "monthly/$1.99",
+	}
+
+	if user.SubscriptionCreatedAt != nil {
+		t := user.SubscriptionCreatedAt.Format(time.DateOnly)
+		resp.MemberSince = &t
+	}
+
+	// MOCKED: NextBillingDate, CancelAtPeriodEnd, PeriodEndDate.
+	// TODO: stripe-go v82 removed Subscription.CurrentPeriodEnd / CancelAtPeriodEnd.
+	// Research SubscriptionItem.CurrentPeriodEnd or use Stripe REST API directly.
+	resp.NextBillingDate = nil
+	resp.CancelAtPeriodEnd = false
+	resp.PeriodEndDate = nil
+
+	writeJSON(w, http.StatusOK, resp)
+}

backend/internal/handlers/address.go

@@ -8,9 +8,9 @@ import (
 	"regexp"
 	"strings"
 
-	"github.com/kjannette/koin-ping/backend-go/internal/domain"
+	"github.com/kjannette/koin-ping/backend/internal/domain"
-	"github.com/kjannette/koin-ping/backend-go/internal/middleware"
+	"github.com/kjannette/koin-ping/backend/internal/middleware"
-	"github.com/kjannette/koin-ping/backend-go/internal/models"
+	"github.com/kjannette/koin-ping/backend/internal/models"
 )
 
 var ethAddressRe = regexp.MustCompile(`^0x[a-fA-F0-9]{40}$`)

backend/internal/handlers/alert_event.go

@@ -5,9 +5,9 @@ import (
 	"net/http"
 	"strconv"
 
-	"github.com/kjannette/koin-ping/backend-go/internal/domain"
+	"github.com/kjannette/koin-ping/backend/internal/domain"
-	"github.com/kjannette/koin-ping/backend-go/internal/middleware"
+	"github.com/kjannette/koin-ping/backend/internal/middleware"
-	"github.com/kjannette/koin-ping/backend-go/internal/models"
+	"github.com/kjannette/koin-ping/backend/internal/models"
 )
 
 // AlertEventHandler handles HTTP requests for alert event history.

backend/internal/handlers/alert_rule.go

@@ -9,9 +9,9 @@ import (
 	"strconv"
 	"strings"
 
-	"github.com/kjannette/koin-ping/backend-go/internal/domain"
+	"github.com/kjannette/koin-ping/backend/internal/domain"
-	"github.com/kjannette/koin-ping/backend-go/internal/middleware"
+	"github.com/kjannette/koin-ping/backend/internal/middleware"
-	"github.com/kjannette/koin-ping/backend-go/internal/models"
+	"github.com/kjannette/koin-ping/backend/internal/models"
 )
 
 var errThresholdFormat = errors.New("unsupported threshold format")

backend/internal/handlers/email_digest.go

@@ -4,9 +4,9 @@ import (
 	"log"
 	"net/http"
 
-	"github.com/kjannette/koin-ping/backend-go/internal/middleware"
+	"github.com/kjannette/koin-ping/backend/internal/middleware"
-	"github.com/kjannette/koin-ping/backend-go/internal/models"
+	"github.com/kjannette/koin-ping/backend/internal/models"
-	"github.com/kjannette/koin-ping/backend-go/internal/services"
+	"github.com/kjannette/koin-ping/backend/internal/services"
 )
 
 type EmailDigestHandler struct {

backend/internal/handlers/notification_config.go

@@ -7,11 +7,11 @@ import (
 	"regexp"
 	"strings"
 
-	"github.com/kjannette/koin-ping/backend-go/internal/config"
+	"github.com/kjannette/koin-ping/backend/internal/config"
-	"github.com/kjannette/koin-ping/backend-go/internal/domain"
+	"github.com/kjannette/koin-ping/backend/internal/domain"
-	"github.com/kjannette/koin-ping/backend-go/internal/middleware"
+	"github.com/kjannette/koin-ping/backend/internal/middleware"
-	"github.com/kjannette/koin-ping/backend-go/internal/models"
+	"github.com/kjannette/koin-ping/backend/internal/models"
-	"github.com/kjannette/koin-ping/backend-go/internal/notifications"
+	"github.com/kjannette/koin-ping/backend/internal/notifications"
 )
 
 var emailRe = regexp.MustCompile(`^[^\s@]+@[^\s@]+\.[^\s@]+$`)

backend/internal/handlers/status.go

@@ -5,7 +5,7 @@ import (
 	"net/http"
 	"time"
 
-	"github.com/kjannette/koin-ping/backend-go/internal/models"
+	"github.com/kjannette/koin-ping/backend/internal/models"
 )
 
 // StatusHandler handles the system status endpoint.

backend/internal/handlers/stripe.go

@@ -7,12 +7,13 @@ import (
 	"net/http"
 
 	"github.com/stripe/stripe-go/v82"
+	portalsession "github.com/stripe/stripe-go/v82/billingportal/session"
 	checkoutsession "github.com/stripe/stripe-go/v82/checkout/session"
 	"github.com/stripe/stripe-go/v82/webhook"
 
-	"github.com/kjannette/koin-ping/backend-go/internal/config"
+	"github.com/kjannette/koin-ping/backend/internal/config"
-	"github.com/kjannette/koin-ping/backend-go/internal/middleware"
+	"github.com/kjannette/koin-ping/backend/internal/middleware"
-	"github.com/kjannette/koin-ping/backend-go/internal/models"
+	"github.com/kjannette/koin-ping/backend/internal/models"
 )
 
 const webhookMaxBodyBytes = 65536
@@ -139,6 +140,38 @@ func (h *StripeHandler) VerifyCheckoutSession(w http.ResponseWriter, r *http.Req
 	writeJSON(w, http.StatusOK, map[string]string{"subscription_status": "active"})
 }
 
+// CreatePortalSession creates a Stripe Billing Portal session so the user can
+// manage their subscription (cancel, update payment method, view invoices).
+func (h *StripeHandler) CreatePortalSession(w http.ResponseWriter, r *http.Request) {
+	userID := middleware.GetUserID(r.Context())
+
+	user, err := h.users.GetByID(r.Context(), userID)
+	if err != nil || user == nil {
+		log.Printf("Portal: failed to get user %s: %v", userID, err)
+		writeError(w, http.StatusInternalServerError, "INTERNAL_ERROR", "Failed to load user")
+		return
+	}
+
+	if user.StripeCustomerID == nil || *user.StripeCustomerID == "" {
+		writeError(w, http.StatusBadRequest, "NO_CUSTOMER", "No Stripe customer on file")
+		return
+	}
+
+	params := &stripe.BillingPortalSessionParams{
+		Customer:  user.StripeCustomerID,
+		ReturnURL: stripe.String(h.cfg.FrontendURL + "/account"),
+	}
+
+	s, err := portalsession.New(params)
+	if err != nil {
+		log.Printf("Portal: failed to create portal session: %v", err)
+		writeError(w, http.StatusInternalServerError, "STRIPE_ERROR", "Failed to create portal session")
+		return
+	}
+
+	writeJSON(w, http.StatusOK, map[string]string{"url": s.URL})
+}
+
 // HandleWebhook processes incoming Stripe webhook events.
 // This endpoint must NOT require authentication (Stripe calls it directly).
 func (h *StripeHandler) HandleWebhook(w http.ResponseWriter, r *http.Request) {

backend/internal/middleware/auth.go

@@ -8,8 +8,8 @@ import (
 	"net/http"
 	"strings"
 
-	fbauth "github.com/kjannette/koin-ping/backend-go/internal/firebase"
+	fbauth "github.com/kjannette/koin-ping/backend/internal/firebase"
-	"github.com/kjannette/koin-ping/backend-go/internal/models"
+	"github.com/kjannette/koin-ping/backend/internal/models"
 )
 
 type contextKey string

backend/internal/models/address.go

@@ -6,7 +6,7 @@ import (
 
 	"github.com/jackc/pgx/v5"
 	"github.com/jackc/pgx/v5/pgxpool"
-	"github.com/kjannette/koin-ping/backend-go/internal/domain"
+	"github.com/kjannette/koin-ping/backend/internal/domain"
 )
 
 type AddressModel struct {

backend/internal/models/alert_event.go

@@ -6,7 +6,7 @@ import (
 
 	"github.com/jackc/pgx/v5"
 	"github.com/jackc/pgx/v5/pgxpool"
-	"github.com/kjannette/koin-ping/backend-go/internal/domain"
+	"github.com/kjannette/koin-ping/backend/internal/domain"
 )
 
 type AlertEventModel struct {

backend/internal/models/alert_rule.go

@@ -6,7 +6,7 @@ import (
 
 	"github.com/jackc/pgx/v5"
 	"github.com/jackc/pgx/v5/pgxpool"
-	"github.com/kjannette/koin-ping/backend-go/internal/domain"
+	"github.com/kjannette/koin-ping/backend/internal/domain"
 )
 
 type AlertRuleModel struct {

backend/internal/models/checkpoint.go

@@ -7,7 +7,7 @@ import (
 
 	"github.com/jackc/pgx/v5"
 	"github.com/jackc/pgx/v5/pgxpool"
-	"github.com/kjannette/koin-ping/backend-go/internal/domain"
+	"github.com/kjannette/koin-ping/backend/internal/domain"
 )
 
 type CheckpointModel struct {

backend/internal/models/notification_config.go

@@ -6,7 +6,7 @@ import (
 
 	"github.com/jackc/pgx/v5"
 	"github.com/jackc/pgx/v5/pgxpool"
-	"github.com/kjannette/koin-ping/backend-go/internal/domain"
+	"github.com/kjannette/koin-ping/backend/internal/domain"
 )
 
 type NotificationConfigModel struct {

backend/internal/models/user.go

@@ -6,7 +6,7 @@ import (
 
 	"github.com/jackc/pgx/v5"
 	"github.com/jackc/pgx/v5/pgxpool"
-	"github.com/kjannette/koin-ping/backend-go/internal/domain"
+	"github.com/kjannette/koin-ping/backend/internal/domain"
 )
 
 type UserModel struct {

backend/internal/notifications/discord.go

@@ -21,17 +21,14 @@ const (
 	colorBlue   = 0x0099ff
 )
 
-// discordHTTPClient is a shared HTTP client with a timeout for Discord requests.
 var discordHTTPClient = &http.Client{ //nolint:gochecknoglobals
 	Timeout: discordHTTPTimeoutSeconds * time.Second,
 }
 
-// DiscordNotifier sends alert notifications via a Discord webhook.
+//  sends alert notifications via a Discord webhook.
 type DiscordNotifier struct {
 	WebhookURL string
 }
-
-// Send implements Notifier for Discord.
 func (d *DiscordNotifier) Send(_ context.Context, message string, meta AlertMetadata) error {
 	_, err := SendDiscordNotification(d.WebhookURL, message, meta)
 	return err
@@ -104,8 +101,12 @@ func SendDiscordNotification(webhookURL, message string, meta AlertMetadata) (bo
 	defer resp.Body.Close()
 
 	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		err := fmt.Errorf("discord webhook failed: HTTP %d", resp.StatusCode)
 		log.Printf("Discord webhook failed: HTTP %d", resp.StatusCode)
-		return false, fmt.Errorf("discord webhook failed: HTTP %d", resp.StatusCode)
+		if isPermanentStatusCode(resp.StatusCode) {
+			return false, &PermanentError{Err: err}
+		}
+		return false, err
 	}
 
 	return true, nil

backend/internal/notifications/email.go

@@ -10,14 +10,12 @@ import (
 	"time"
 )
 
-// EmailNotifier sends alert notifications via email (Resend).
 type EmailNotifier struct {
 	APIKey string
 	From   string
 	To     string
 }
 
-// Send implements Notifier for email.
 func (e *EmailNotifier) Send(_ context.Context, message string, meta AlertMetadata) error {
 	_, err := SendEmailNotification(e.APIKey, e.From, e.To, message, meta)
 	return err
@@ -99,8 +97,12 @@ func SendEmailNotification(apiKey, fromAddress, toAddress, message string, meta
 	defer resp.Body.Close()
 
 	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		err := fmt.Errorf("resend API failed: HTTP %d", resp.StatusCode)
 		log.Printf("Resend API failed: HTTP %d", resp.StatusCode)
-		return false, fmt.Errorf("resend API failed: HTTP %d", resp.StatusCode)
+		if isPermanentStatusCode(resp.StatusCode) {
+			return false, &PermanentError{Err: err}
+		}
+		return false, err
 	}
 
 	return true, nil

backend/internal/notifications/notifier.go

@@ -0,0 +1,38 @@
+package notifications
+
+import (
+	"context"
+	"errors"
+	"net/http"
+)
+
+// AlertMetadata holds context about the alert being sent.
+type AlertMetadata struct {
+	TxHash       string
+	AddressLabel string
+	AlertType    string
+	Address      string
+}
+
+type Notifier interface {
+	Send(ctx context.Context, message string, meta AlertMetadata) error
+}
+
+// PermanentError wraps errors that should not be retried (e.g. 401, 403, 404).
+type PermanentError struct{ Err error }
+
+func (e *PermanentError) Error() string { return e.Err.Error() }
+func (e *PermanentError) Unwrap() error { return e.Err }
+
+func IsPermanent(err error) bool {
+	var p *PermanentError
+	return errors.As(err, &p)
+}
+
+func isPermanentStatusCode(code int) bool {
+	return code == http.StatusUnauthorized ||
+		code == http.StatusForbidden ||
+		code == http.StatusNotFound ||
+		code == http.StatusMethodNotAllowed ||
+		code == http.StatusGone
+}

backend/internal/notifications/slack.go

@@ -87,8 +87,12 @@ func SendSlackNotification(webhookURL, message string, meta AlertMetadata) (bool
 	defer resp.Body.Close()
 
 	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		err := fmt.Errorf("slack webhook failed: HTTP %d", resp.StatusCode)
 		log.Printf("Slack webhook failed: HTTP %d", resp.StatusCode)
-		return false, fmt.Errorf("slack webhook failed: HTTP %d", resp.StatusCode)
+		if isPermanentStatusCode(resp.StatusCode) {
+			return false, &PermanentError{Err: err}
+		}
+		return false, err
 	}
 
 	return true, nil

backend/internal/notifications/telegram.go

@@ -63,8 +63,12 @@ func SendTelegramNotification(botToken, chatID, message string, meta AlertMetada
 	defer resp.Body.Close()
 
 	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		err := fmt.Errorf("telegram API failed: HTTP %d", resp.StatusCode)
 		log.Printf("Telegram API failed: HTTP %d", resp.StatusCode)
-		return false, fmt.Errorf("telegram API failed: HTTP %d", resp.StatusCode)
+		if isPermanentStatusCode(resp.StatusCode) {
+			return false, &PermanentError{Err: err}
+		}
+		return false, err
 	}
 
 	return true, nil

backend/internal/protocols/ethereum/jsonrpc.go

@@ -12,18 +12,20 @@ import (
 	"strings"
 	"time"
 
-	"github.com/kjannette/koin-ping/backend-go/internal/domain"
+	"github.com/kjannette/koin-ping/backend/internal/domain"
 )
 
 const (
-	rpcTimeoutMS    = 30000
+	rpcTimeoutMS      = 30000
-	rpcMaxRetries   = 3
+	rpcMaxRetries     = 3
-	rpcRetryBaseMS  = 1000
+	rpcRetryBaseMS    = 2000
+	rpcMinIntervalMS  = 1000
 )
 
 type JsonRpcEthereum struct {
-	rpcURL string
+	rpcURL     string
-	client *http.Client
+	client     *http.Client
+	lastCallAt time.Time
 }
 
 func NewJsonRpcEthereum(rpcURL string) (*JsonRpcEthereum, error) {
@@ -58,6 +60,8 @@ type rpcError struct {
 }
 
 func (j *JsonRpcEthereum) callRPC(ctx context.Context, method string, params ...interface{}) (json.RawMessage, error) {
+	j.throttle(ctx)
+
 	if params == nil {
 		params = []interface{}{}
 	}
@@ -72,7 +76,25 @@ func (j *JsonRpcEthereum) callRPC(ctx context.Context, method string, params ...
 		return nil, fmt.Errorf("marshal RPC request: %w", err)
 	}
 
-	return j.callWithRetry(ctx, method, body)
+	result, callErr := j.callWithRetry(ctx, method, body)
+	j.lastCallAt = time.Now()
+
+	return result, callErr
+}
+
+func (j *JsonRpcEthereum) throttle(ctx context.Context) {
+	if j.lastCallAt.IsZero() {
+		return
+	}
+	minInterval := time.Duration(rpcMinIntervalMS) * time.Millisecond
+	elapsed := time.Since(j.lastCallAt)
+	if elapsed >= minInterval {
+		return
+	}
+	select {
+	case <-ctx.Done():
+	case <-time.After(minInterval - elapsed):
+	}
 }
 
 // callWithRetry executes a JSON-RPC POST with exponential backoff on transient errors.

backend/internal/protocols/ethereum/observer.go

@@ -3,7 +3,7 @@ package ethereum
 import (
 	"context"
 
-	"github.com/kjannette/koin-ping/backend-go/internal/domain"
+	"github.com/kjannette/koin-ping/backend/internal/domain"
 )
 
 // EthereumObserver defines the interface for blockchain interaction.

backend/internal/services/email_digest.go

@@ -9,7 +9,7 @@ import (
 	"net/http"
 	"time"
 
-	"github.com/kjannette/koin-ping/backend-go/internal/models"
+	"github.com/kjannette/koin-ping/backend/internal/models"
 )
 
 const (
@@ -20,7 +20,7 @@ const (
 
 var digestHTTPClient = &http.Client{Timeout: emailHTTPTimeout} //nolint:gochecknoglobals
 
-// EmailDigestService handles email setup and digest sending via Resend.
+// handles email setup and digest sending via Resend.
 type EmailDigestService struct {
 	apiKey      string
 	fromAddress string
@@ -66,7 +66,6 @@ func (s *EmailDigestService) SetupEmail(toAddress string) error {
 	return s.send(toAddress, "Koin Ping — Email Alerts Configured", html)
 }
 
-// SendDigest compiles recent alert events for a user and sends a digest email.
 func (s *EmailDigestService) SendDigest(ctx context.Context, userID, toAddress string) error {
 	if !s.Configured() {
 		return fmt.Errorf("email service not configured: RESEND_API_KEY not set") //nolint:err113
@@ -131,8 +130,6 @@ func (s *EmailDigestService) SendDigest(ctx context.Context, userID, toAddress s
 	return s.send(toAddress, subject, html)
 }
 
-// SendDigestsForAllUsers sends a digest email to every user that has
-// notifications enabled and an email configured.
 func (s *EmailDigestService) SendDigestsForAllUsers(ctx context.Context) (int, error) {
 	if !s.Configured() {
 		return 0, nil

backend/internal/services/evaluator.go

@@ -4,19 +4,23 @@ import (
 	"context"
 	"fmt"
 	"log"
+	"sync"
 	"time"
 
-	"github.com/kjannette/koin-ping/backend-go/internal/domain"
+	"golang.org/x/sync/semaphore"
-	"github.com/kjannette/koin-ping/backend-go/internal/models"
+
-	"github.com/kjannette/koin-ping/backend-go/internal/notifications"
+	"github.com/kjannette/koin-ping/backend/internal/domain"
-	"github.com/kjannette/koin-ping/backend-go/internal/protocols/ethereum"
+	"github.com/kjannette/koin-ping/backend/internal/models"
-	"github.com/kjannette/koin-ping/backend-go/internal/wei"
+	"github.com/kjannette/koin-ping/backend/internal/notifications"
+	"github.com/kjannette/koin-ping/backend/internal/protocols/ethereum"
+	"github.com/kjannette/koin-ping/backend/internal/wei"
 )
 
 const (
 	notificationTimeout    = 30 * time.Second
 	notificationMaxRetries = 3
 	notificationRetryBase  = time.Second
+	maxConcurrentNotifications = 5
 )
 
 type EvaluatorService struct {
@@ -27,6 +31,8 @@ type EvaluatorService struct {
 	notifConfigs *models.NotificationConfigModel
 	resendAPIKey string
 	emailFrom    string
+	notifSem     *semaphore.Weighted
+	notifWg      sync.WaitGroup
 }
 
 func NewEvaluatorService(
@@ -46,6 +52,7 @@ func NewEvaluatorService(
 		notifConfigs: notifConfigs,
 		resendAPIKey: resendAPIKey,
 		emailFrom:    emailFrom,
+		notifSem:     semaphore.NewWeighted(maxConcurrentNotifications),
 	}
 }
 
@@ -189,7 +196,14 @@ func (s *EvaluatorService) fireAlert(ctx context.Context, rule domain.AlertRule,
 	if addr != nil {
 		userID := addr.UserID
 		address := addr.Address
+		if err := s.notifSem.Acquire(ctx, 1); err != nil {
+			log.Printf("Failed to acquire notification semaphore for rule %d: %v", rule.ID, err)
+			return nil
+		}
+		s.notifWg.Add(1)
 		go func() {
+			defer s.notifSem.Release(1)
+			defer s.notifWg.Done()
 			notifCtx, cancel := context.WithTimeout(context.Background(), notificationTimeout)
 			defer cancel()
 			s.sendNotification(notifCtx, userID, message, obs, addressLabel, rule, address)
@@ -199,6 +213,11 @@ func (s *EvaluatorService) fireAlert(ctx context.Context, rule domain.AlertRule,
 	return nil
 }
 
+// WaitForNotifications blocks until all in-flight notification goroutines finish.
+func (s *EvaluatorService) WaitForNotifications() {
+	s.notifWg.Wait()
+}
+
 func (s *EvaluatorService) buildNotifiers(cfg *domain.NotificationConfig) []notifications.Notifier {
 	var notifiers []notifications.Notifier
 
@@ -242,8 +261,14 @@ func sendWithRetry(ctx context.Context, n notifications.Notifier, message string
 		}
 
 		if err := n.Send(ctx, message, meta); err != nil {
-			log.Printf("Notification attempt %d/%d failed: %v", attempt+1, notificationMaxRetries, err)
 			lastErr = err
+
+			if notifications.IsPermanent(err) {
+				log.Printf("Permanent notification failure, skipping retries: %v", err)
+				return err
+			}
+
+			log.Printf("Notification attempt %d/%d failed: %v", attempt+1, notificationMaxRetries, err)
 			continue
 		}
 

backend/internal/services/observer.go

@@ -5,9 +5,9 @@ import (
 	"log"
 	"strings"
 
-	"github.com/kjannette/koin-ping/backend-go/internal/domain"
+	"github.com/kjannette/koin-ping/backend/internal/domain"
-	"github.com/kjannette/koin-ping/backend-go/internal/models"
+	"github.com/kjannette/koin-ping/backend/internal/models"
-	"github.com/kjannette/koin-ping/backend-go/internal/protocols/ethereum"
+	"github.com/kjannette/koin-ping/backend/internal/protocols/ethereum"
 )
 
 const maxBlocksPerRun = 100

frontend/src/App.jsx

@@ -7,6 +7,7 @@ import Subscribe from "./pages/subscribe/subscribe";
 import Addresses from "./pages/addresses/Addresses";
 import Alerts from "./pages/alerts/Alerts";
 import AlertHistory from "./pages/alertHistory/AlertHistory";
+import Account from "./pages/user_account/Account";
 
 export default function App() {
   const { currentUser } = useAuth();
@@ -30,6 +31,7 @@ export default function App() {
         <Route path="/addresses" element={<Addresses />} />
         <Route path="/alerts" element={<Alerts />} />
         <Route path="/alertevents" element={<AlertHistory />} />
+        <Route path="/account" element={<Account />} />
         <Route path="/subscribe" element={<Subscribe />} />
         <Route path="*" element={<Navigate to="/addresses" />} />
       </Routes>

frontend/src/api/account.js

@@ -0,0 +1,25 @@
+import { getAuthHeaders } from "./authHeaders";
+import { API_BASE } from "./config";
+
+export async function getAccount() {
+    const headers = await getAuthHeaders();
+    const res = await fetch(`${API_BASE}/user/account`, { headers });
+    if (!res.ok) {
+        const data = await res.json();
+        throw new Error(data.message || "Failed to load account");
+    }
+    return res.json();
+}
+
+export async function createPortalSession() {
+    const headers = await getAuthHeaders();
+    const res = await fetch(`${API_BASE}/stripe/create-portal-session`, {
+        method: "POST",
+        headers,
+    });
+    if (!res.ok) {
+        const data = await res.json();
+        throw new Error(data.message || "Failed to create portal session");
+    }
+    return res.json();
+}

frontend/src/components/Navbar.css

@@ -8,6 +8,19 @@
   border-bottom: 1px solid var(--color-border-light);
 }
 
+/* ── Left Group: Brand + Links ───────────────────────────── */
+
+.navbar__left {
+  display: flex;
+  align-items: center;
+  gap: 0.5rem;
+}
+
+.navbar__brand-group {
+  display: flex;
+  align-items: center;
+}
+
 .navbar__brand {
   font-weight: 700;
   font-size: 1.4rem;
@@ -38,11 +51,33 @@
   background-color: var(--color-bg-card);
 }
 
+/* ── Right Group: Email + Logout + Hamburger ─────────────── */
+
+.navbar__right {
+  display: flex;
+  align-items: center;
+  gap: 1rem;
+}
+
 .navbar__user {
   font-size: 1.275rem;
   color: #777;
 }
 
+.navbar__user-link {
+  color: var(--color-primary);
+  text-decoration: none;
+  transition: color 0.15s ease;
+}
+
+.navbar__user-link:hover {
+  color: var(--color-primary-hover);
+}
+
+.navbar__user-link--mobile {
+  display: none;
+}
+
 .navbar__logout {
   padding: 0.4rem 1rem;
   font-size: 1.275rem;
@@ -54,3 +89,79 @@
   cursor: pointer;
   transition: all 0.15s ease;
 }
+
+/* ── Hamburger Icon (hidden on desktop) ──────────────────── */
+
+.navbar__hamburger {
+  display: none;
+  flex-direction: column;
+  justify-content: center;
+  gap: 5px;
+  background: none;
+  border: none;
+  cursor: pointer;
+  padding: 4px;
+}
+
+.navbar__hamburger-bar {
+  display: block;
+  width: 28px;
+  height: 3px;
+  background-color: var(--color-brand);
+  border-radius: 2px;
+}
+
+/* ── Responsive: Tablet & below (≤ 768px) ────────────────── */
+
+@media (max-width: 768px) {
+  .navbar {
+    padding: 0.75rem 1rem;
+  }
+
+  .navbar__brand-group {
+    flex-direction: column;
+    align-items: flex-start;
+  }
+
+  .navbar__brand {
+    margin-right: 0;
+    font-size: 1.25rem;
+  }
+
+  .navbar__links {
+    display: none;
+  }
+
+  .navbar__user-link--mobile {
+    display: block;
+    font-size: 0.95rem;
+  }
+
+  .navbar__user-link--desktop {
+    display: none;
+  }
+
+  .navbar__logout {
+    display: none;
+  }
+
+  .navbar__hamburger {
+    display: flex;
+  }
+}
+
+/* ── Responsive: Mobile (≤ 480px) ────────────────────────── */
+
+@media (max-width: 480px) {
+  .navbar {
+    padding: 0.75rem;
+  }
+
+  .navbar__brand {
+    font-size: 1.15rem;
+  }
+
+  .navbar__user-link--mobile {
+    font-size: 0.85rem;
+  }
+}

frontend/src/components/Navbar.jsx

@@ -1,5 +1,7 @@
+import { useState } from "react";
 import { Link, useLocation } from "react-router-dom";
 import { useAuth } from "../contexts/AuthContext";
+import NavPanel from "./navPanel/NavPanel";
 import "./Navbar.css";
 
 const navLinks = [
@@ -11,35 +13,59 @@ const navLinks = [
 export default function Navbar() {
   const { currentUser, logout } = useAuth();
   const location = useLocation();
+  const [isNavPanelOpen, setIsNavPanelOpen] = useState(false);
 
   if (!currentUser) return null;
 
   return (
-    <nav className="navbar">
+    <>
-      <div className="flex flex--center gap-sm">
+      <nav className="navbar">
-        <span className="navbar__brand">Koin Ping</span>
+        <div className="navbar__left">
-        <div className="navbar__links">
+          <div className="navbar__brand-group">
-          {navLinks.map(({ to, label }) => {
+            <span className="navbar__brand">Koin Ping</span>
-            const isActive = location.pathname === to;
+            <Link to="/account" className="navbar__user-link navbar__user-link--mobile">
-            return (
+              {currentUser.email}
-              <Link
+            </Link>
-                key={to}
+          </div>
-                to={to}
+          <div className="navbar__links">
-                className={`navbar__link ${isActive ? "navbar__link--active" : ""}`}
+            {navLinks.map(({ to, label }) => {
-              >
+              const isActive = location.pathname === to;
-                {label}
+              return (
-              </Link>
+                <Link
-            );
+                  key={to}
-          })}
+                  to={to}
+                  className={`navbar__link ${isActive ? "navbar__link--active" : ""}`}
+                >
+                  {label}
+                </Link>
+              );
+            })}
+          </div>
         </div>
-      </div>
 
-      <div className="flex flex--center gap-lg">
+        <div className="navbar__right">
-        <span className="navbar__user">{currentUser.email}</span>
+          <Link to="/account" className="navbar__user navbar__user-link navbar__user-link--desktop">
-        <button onClick={logout} className="navbar__logout">
+            {currentUser.email}
-          Logout
+          </Link>
-        </button>
+          <button onClick={logout} className="navbar__logout">
-      </div>
+            Logout
-    </nav>
+          </button>
+          <button
+            className="navbar__hamburger"
+            onClick={() => setIsNavPanelOpen(true)}
+            aria-label="Open navigation menu"
+          >
+            <span className="navbar__hamburger-bar" />
+            <span className="navbar__hamburger-bar" />
+            <span className="navbar__hamburger-bar" />
+          </button>
+        </div>
+      </nav>
+
+      <NavPanel
+        isOpen={isNavPanelOpen}
+        onClose={() => setIsNavPanelOpen(false)}
+      />
+    </>
   );
 }

frontend/src/components/navPanel/NavPanel.css

@@ -0,0 +1,78 @@
+/* ── Overlay Backdrop ─────────────────────────────────────── */
+
+.nav-panel__overlay {
+  position: fixed;
+  inset: 0;
+  background-color: rgba(0, 0, 0, 0.45);
+  opacity: 0;
+  pointer-events: none;
+  transition: opacity 0.3s ease;
+  z-index: 900;
+}
+
+.nav-panel__overlay--visible {
+  opacity: 1;
+  pointer-events: auto;
+}
+
+/* ── Slide-out Panel ─────────────────────────────────────── */
+
+.nav-panel {
+  position: fixed;
+  top: 0;
+  left: 0;
+  width: 260px;
+  height: 100%;
+  background-color: var(--color-bg-elevated);
+  border-right: 1px solid var(--color-border);
+  transform: translateX(-100%);
+  transition: transform 0.3s ease;
+  z-index: 950;
+  display: flex;
+  flex-direction: column;
+  padding: 1.5rem 0;
+}
+
+.nav-panel--open {
+  transform: translateX(0);
+}
+
+/* ── Nav Links ───────────────────────────────────────────── */
+
+.nav-panel__nav {
+  display: flex;
+  flex-direction: column;
+  flex: 1;
+}
+
+.nav-panel__link {
+  padding: 0.9rem 1.5rem;
+  text-decoration: none;
+  font-size: 1.3rem;
+  font-weight: 200;
+  color: var(--color-text-subtle);
+  border-left: 3px solid transparent;
+  transition: background-color 0.15s ease, color 0.15s ease;
+}
+
+.nav-panel__link--active {
+  font-weight: 600;
+  color: var(--color-text);
+  background-color: var(--color-bg-card);
+  border-left-color: var(--color-brand);
+}
+
+/* ── Logout Button ───────────────────────────────────────── */
+
+.nav-panel__logout {
+  margin: 1rem 1.5rem;
+  padding: 0.5rem 1rem;
+  font-size: 1.15rem;
+  font-weight: 400;
+  background-color: transparent;
+  color: var(--color-text-subtle);
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-lg);
+  cursor: pointer;
+  transition: all 0.15s ease;
+}

frontend/src/components/navPanel/NavPanel.jsx

@@ -0,0 +1,52 @@
+import { Link, useLocation } from "react-router-dom";
+import { useAuth } from "../../contexts/AuthContext";
+import "./NavPanel.css";
+
+const navLinks = [
+  { to: "/addresses", label: "Addresses" },
+  { to: "/alerts", label: "Configure Alerts" },
+  { to: "/alertevents", label: "Alert Event History" },
+];
+
+export default function NavPanel({ isOpen, onClose }) {
+  const { logout } = useAuth();
+  const location = useLocation();
+
+  const handleNavClick = () => {
+    onClose();
+  };
+
+  const handleLogout = () => {
+    onClose();
+    logout();
+  };
+
+  return (
+    <>
+      <div
+        className={`nav-panel__overlay${isOpen ? " nav-panel__overlay--visible" : ""}`}
+        onClick={onClose}
+      />
+      <aside className={`nav-panel${isOpen ? " nav-panel--open" : ""}`}>
+        <nav className="nav-panel__nav">
+          {navLinks.map(({ to, label }) => {
+            const isActive = location.pathname === to;
+            return (
+              <Link
+                key={to}
+                to={to}
+                className={`nav-panel__link${isActive ? " nav-panel__link--active" : ""}`}
+                onClick={handleNavClick}
+              >
+                {label}
+              </Link>
+            );
+          })}
+        </nav>
+        <button onClick={handleLogout} className="nav-panel__logout">
+          Logout
+        </button>
+      </aside>
+    </>
+  );
+}

frontend/src/index.css

@@ -355,4 +355,74 @@ button {
 .text-white-sm {
   color: white;
   font-size: 0.85rem;
+}
+
+/* ── Responsive Breakpoints ──────────────────────────────── */
+/* Mobile:  <= 480px                                          */
+/* Tablet:  481px – 768px                                     */
+/* Laptop:  769px – 1024px                                    */
+/* Desktop: >= 1025px (default styles above)                  */
+
+/* Laptop & below */
+@media (max-width: 1024px) {
+  .page--wide {
+    max-width: 100%;
+  }
+}
+
+/* Tablet & below */
+@media (max-width: 768px) {
+  html {
+    font-size: 13px;
+  }
+
+  .page {
+    padding: 1.25rem;
+  }
+
+  .btn--lg {
+    padding: 0.6rem 1.2rem;
+  }
+
+  h1 {
+    font-size: 1.75rem;
+  }
+
+  h2 {
+    font-size: 1.4rem;
+  }
+
+  h3 {
+    font-size: 1.15rem;
+  }
+}
+
+/* Mobile */
+@media (max-width: 480px) {
+  html {
+    font-size: 12px;
+  }
+
+  .page {
+    padding: 1rem 0.75rem;
+  }
+
+  .form-control,
+  .form-select {
+    font-size: 0.95rem;
+  }
+
+  .btn {
+    padding: 0.45rem 0.85rem;
+    font-size: 0.95rem;
+  }
+
+  .btn--lg {
+    padding: 0.55rem 1rem;
+    font-size: 1rem;
+  }
+
+  .section {
+    padding: 0.75rem;
+  }
 }

frontend/src/pages/addresses/Addresses.css

@@ -28,3 +28,13 @@
   margin-left: 1rem;
   flex-shrink: 0;
 }
+
+/* ── Addresses Responsive ────────────────────────────────── */
+
+@media (max-width: 480px) {
+  .address__remove {
+    margin-left: 0.5rem;
+    padding: 0.25rem 0.5rem;
+    font-size: 0.8rem;
+  }
+}

frontend/src/pages/alerts/Alerts.css

@@ -61,3 +61,54 @@
   gap: 0.75rem;
   margin-top: 1rem;
 }
+
+/* ── Alerts Page Responsive ──────────────────────────────── */
+
+/* Laptop: tighten the gap */
+@media (max-width: 1024px) {
+  .alerts-grid {
+    gap: 1.5rem;
+  }
+}
+
+/* Tablet & below: collapse to single column */
+@media (max-width: 768px) {
+  .alerts-grid {
+    grid-template-columns: 1fr;
+    gap: 2.5rem;
+  }
+}
+
+/* Mobile: compact spacing */
+@media (max-width: 480px) {
+  .alerts-grid {
+    gap: 2rem;
+  }
+
+  .alerts__address-info {
+    padding: 0.75rem;
+    margin-bottom: 1.25rem;
+  }
+
+  .alerts__rule {
+    padding: 0.75rem;
+  }
+
+  .alerts__rule .flex--between {
+    flex-direction: column;
+    gap: 0.75rem;
+  }
+
+  .alerts__save-test {
+    flex-direction: column;
+  }
+
+  .alerts__save-test .btn--lg {
+    width: 100%;
+    text-align: center;
+  }
+
+  .alerts__email-buttons {
+    flex-direction: column;
+  }
+}

frontend/src/pages/login/Login.css

@@ -1,19 +1,38 @@
 .login-page {
-  min-height: 100vh;
+  position: relative;
-  background-image: url(/ping.png);
+  width: 100vw;
-  background-size: 67%;
+  height: 100vh;
-  background-position: center;
+  overflow: hidden;
-  background-repeat: no-repeat;
+  background-color: #000000;
+}
+
+.login-bg-video {
+  position: absolute;
+  top: 50%;
+  left: 50%;
+  min-width: 100%;
+  min-height: 100%;
+  width: auto;
+  height: auto;
+  transform: translate(-50%, -50%);
+  object-fit: cover;
+  z-index: 0;
+  filter: grayscale(85%);
+  -webkit-filter: grayscale(85%);
+  opacity: 0.05;
 }
 
 .login-card {
+  position: relative;
+  z-index: 1;
   max-width: 400px;
-  margin: 20px auto;
+  margin: 0 auto;
   padding: 2rem;
   padding-top: 8rem;
   border: 1px solid var(--color-border-light);
   border-radius: var(--radius-xl);
   background-color: rgba(0, 0, 0, 0.75);
+  top: 20px;
 }
 
 .login-heading {
@@ -32,7 +51,6 @@
   padding: 0.75rem;
   font-size: 1.2rem;
   margin-top: 16px;
-  ;
 }
 
 .login-footer {
@@ -55,10 +73,44 @@
   }
 }
 
-.login-form-hidden {
+.login-card-fadein {
   opacity: 0;
+  animation: fadeIn 2s ease-in-out forwards;
+  animation-delay: 3s;
 }
 
-.login-form-visible {
+.login-tagline {
+  position: relative;
+  z-index: 1;
+  max-width: 630px;
+  margin: 5rem auto 0;
+  padding-left: 2rem;
+  font-style: italic;
+  color: #FFFFFF;
+  font-size: 1.5rem;
+  line-height: 1.5;
+}
+
+.login-interactive-fadein {
+  opacity: 0;
   animation: fadeIn 2s ease-in-out forwards;
+  animation-delay: 6s;
+}
+
+/* ── Login Responsive ────────────────────────────────────── */
+
+@media (max-width: 480px) {
+  .login-card {
+    max-width: 100%;
+    margin: 0 0.75rem;
+    padding: 1.5rem;
+    padding-top: 6rem;
+  }
+
+  .login-tagline {
+    margin-top: 3rem;
+    padding-left: 1rem;
+    padding-right: 1rem;
+    font-size: 1.25rem;
+  }
 }

frontend/src/pages/login/Login.jsx

@@ -5,7 +5,6 @@ import Input from "../../components/Input";
 import "./Login.css";
 
 export default function Login() {
-  const [isVisible, setIsVisible] = useState(false);
   const [email, setEmail] = useState("");
   const [password, setPassword] = useState("");
   const [error, setError] = useState("");
@@ -36,12 +35,22 @@ export default function Login() {
 
   return (
     <div className="login-page">
-      <div className="login-card" onMouseEnter={() => setIsVisible(true)}>
+      <video
+        autoPlay
+        loop
+        muted
+        playsInline
+        className="login-bg-video"
+      >
+        <source src="/koin_spin.mp4" type="video/mp4" />
+      </video>
+
+      <div className="login-card login-card-fadein">
         <h1 className="login-heading">
           <span className="login-brand">Koin Ping</span> - Login
         </h1>
 
-        <div className={isVisible ? "login-form-visible" : "login-form-hidden"}>
+        <div className="login-interactive-fadein">
           {error && <div className="alert alert--error">{error}</div>}
 
           <form onSubmit={handleSubmit}>
@@ -78,6 +87,11 @@ export default function Login() {
           </div>
         </div>
       </div>
+
+      <p className="login-tagline login-card-fadein">
+        A lightweight, on-chain monitoring system giving users real-time
+        situational awareness over blockchain addresses.
+      </p>
     </div>
   );
 }

frontend/src/pages/subscribe/subscribe.css

@@ -235,4 +235,26 @@
   font-size: 0.8rem;
   margin: 0;
   font-style: italic;
+}
+
+/* ── Subscribe Responsive ────────────────────────────────── */
+
+@media (max-width: 480px) {
+  .subscribe {
+    padding-top: 1.5rem;
+  }
+
+  .subscribe__card {
+    padding: 1.25rem;
+  }
+
+  .progress-bar__connector {
+    width: 24px;
+  }
+
+  .progress-bar__dot {
+    width: 26px;
+    height: 26px;
+    font-size: 0.75rem;
+  }
 }

frontend/src/pages/user_account/Account.css

@@ -0,0 +1,77 @@
+.account-page h1 {
+  font-size: 2rem;
+  font-weight: 200;
+}
+
+.account__section-title {
+  font-size: 1.4rem;
+  font-weight: 400;
+  margin-bottom: 1.25rem;
+  color: var(--color-text);
+  border-bottom: 1px solid var(--color-border-light);
+  padding-bottom: 0.5rem;
+}
+
+.account__row {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  padding: 0.6rem 0;
+  border-bottom: 1px solid var(--color-border-light);
+}
+
+.account__row--last {
+  border-bottom: none;
+}
+
+.account__label {
+  color: var(--color-text-muted);
+  font-size: 1.1rem;
+}
+
+.account__value {
+  color: var(--color-text);
+  font-size: 1.1rem;
+  text-align: right;
+}
+
+.account__uuid {
+  font-size: 0.85rem;
+  color: var(--color-text-dimmed);
+  word-break: break-all;
+  max-width: 60%;
+}
+
+.account__status {
+  font-weight: 600;
+}
+
+.account__status--active {
+  color: var(--color-success-text);
+}
+
+.account__status--canceled {
+  color: var(--color-danger);
+}
+
+.account__status--canceling {
+  color: var(--color-warning);
+}
+
+.account__status--past_due {
+  color: var(--color-error);
+}
+
+.account__portal-section {
+  margin-top: 1.25rem;
+  padding-top: 1rem;
+  border-top: 1px solid var(--color-border-light);
+}
+
+.account__portal-hint {
+  margin-top: 0.5rem;
+}
+
+.account__password-form {
+  max-width: 400px;
+}

frontend/src/pages/user_account/Account.jsx

@@ -0,0 +1,202 @@
+import { useState, useEffect } from "react";
+import { updatePassword } from "firebase/auth";
+import { auth } from "../../firebase/config";
+import { getAccount, createPortalSession } from "../../api/account";
+import "./Account.css";
+
+export default function Account() {
+  const [account, setAccount] = useState(null);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState(null);
+
+  const [newPassword, setNewPassword] = useState("");
+  const [confirmPassword, setConfirmPassword] = useState("");
+  const [passwordMsg, setPasswordMsg] = useState(null);
+  const [passwordErr, setPasswordErr] = useState(null);
+  const [changingPassword, setChangingPassword] = useState(false);
+
+  const [portalLoading, setPortalLoading] = useState(false);
+
+  useEffect(() => {
+    async function fetchAccount() {
+      try {
+        const data = await getAccount();
+        setAccount(data);
+      } catch (err) {
+        setError(err.message);
+      } finally {
+        setLoading(false);
+      }
+    }
+    fetchAccount();
+  }, []);
+
+  async function handlePasswordChange(e) {
+    e.preventDefault();
+    setPasswordMsg(null);
+    setPasswordErr(null);
+
+    if (newPassword.length < 6) {
+      setPasswordErr("Password must be at least 6 characters");
+      return;
+    }
+    if (newPassword !== confirmPassword) {
+      setPasswordErr("Passwords do not match");
+      return;
+    }
+
+    try {
+      setChangingPassword(true);
+      await updatePassword(auth.currentUser, newPassword);
+      setPasswordMsg("Password updated successfully");
+      setNewPassword("");
+      setConfirmPassword("");
+    } catch (err) {
+      setPasswordErr(err.message);
+    } finally {
+      setChangingPassword(false);
+    }
+  }
+
+  async function handleManageSubscription() {
+    try {
+      setPortalLoading(true);
+      const { url } = await createPortalSession();
+      window.location.href = url;
+    } catch (err) {
+      setError(err.message);
+    } finally {
+      setPortalLoading(false);
+    }
+  }
+
+  if (loading) {
+    return <div className="page">Loading...</div>;
+  }
+
+  if (error && !account) {
+    return <div className="page text-error">Error: {error}</div>;
+  }
+
+  const isCanceling = account.cancel_at_period_end;
+  const statusLabel = isCanceling
+    ? "Canceling"
+    : account.subscription_status === "active"
+      ? "Active"
+      : account.subscription_status.charAt(0).toUpperCase() +
+        account.subscription_status.slice(1);
+
+  return (
+    <div className="page account-page">
+      <h1 className="mb-lg">Account</h1>
+
+      {error && <div className="alert alert--error mb-lg">{error}</div>}
+
+      {/* ── Profile Section ──────────────────────── */}
+      <div className="section mb-lg">
+        <h2 className="account__section-title">Profile</h2>
+        <div className="account__row">
+          <span className="account__label">Email</span>
+          <span className="account__value">{account.email}</span>
+        </div>
+        <div className="account__row">
+          <span className="account__label">User Name</span>
+          <span className="account__value">{account.user_name}</span>
+        </div>
+        <div className="account__row account__row--last">
+          <span className="account__label">User ID</span>
+          <span className="account__value text-mono account__uuid">{account.user_id}</span>
+        </div>
+      </div>
+
+      {/* ── Subscription Section ─────────────────── */}
+      <div className="section mb-lg">
+        <h2 className="account__section-title">Subscription</h2>
+        <div className="account__row">
+          <span className="account__label">Plan</span>
+          <span className="account__value">{account.subscription_plan}</span>
+        </div>
+        <div className="account__row">
+          <span className="account__label">Status</span>
+          <span className={`account__value account__status account__status--${isCanceling ? "canceling" : account.subscription_status}`}>
+            {statusLabel}
+          </span>
+        </div>
+        {account.member_since && (
+          <div className="account__row">
+            <span className="account__label">Member Since</span>
+            <span className="account__value">{account.member_since}</span>
+          </div>
+        )}
+        {account.next_billing_date && !isCanceling && (
+          <div className="account__row">
+            <span className="account__label">Next Billing Date</span>
+            <span className="account__value">{account.next_billing_date}</span>
+          </div>
+        )}
+        {isCanceling && account.period_end_date && (
+          <div className="account__row">
+            <span className="account__label">Access Until</span>
+            <span className="account__value">{account.period_end_date}</span>
+          </div>
+        )}
+
+        {isCanceling && (
+          <div className="alert alert--warning mt-md">
+            Your subscription has been canceled and will not renew.
+            You have full access until {account.period_end_date}.
+          </div>
+        )}
+
+        <div className="account__portal-section">
+          <button
+            onClick={handleManageSubscription}
+            disabled={portalLoading}
+            className="btn btn--ghost"
+          >
+            {portalLoading ? "Redirecting..." : "Manage Subscription"}
+          </button>
+          <p className="text-dimmed text-sm account__portal-hint">
+            Cancel subscription, update payment method, or view invoices via Stripe.
+          </p>
+        </div>
+      </div>
+
+      {/* ── Change Password Section ──────────────── */}
+      <div className="section">
+        <h2 className="account__section-title">Change Password</h2>
+
+        {passwordMsg && <div className="alert alert--success mb-md">{passwordMsg}</div>}
+        {passwordErr && <div className="alert alert--error mb-md">{passwordErr}</div>}
+
+        <form onSubmit={handlePasswordChange} className="account__password-form">
+          <div className="form-field">
+            <label className="form-label">New Password</label>
+            <input
+              type="password"
+              className="form-control"
+              value={newPassword}
+              onChange={(e) => setNewPassword(e.target.value)}
+              disabled={changingPassword}
+              required
+            />
+          </div>
+          <div className="form-field form-field--last">
+            <label className="form-label">Confirm Password</label>
+            <input
+              type="password"
+              className="form-control"
+              value={confirmPassword}
+              onChange={(e) => setConfirmPassword(e.target.value)}
+              disabled={changingPassword}
+              required
+            />
+          </div>
+          <button type="submit" disabled={changingPassword} className="btn btn--primary">
+            {changingPassword ? "Updating..." : "Update Password"}
+          </button>
+        </form>
+      </div>
+    </div>
+  );
+}