diff --git a/main.go b/main.go
index e028382..1884cf8 100644
--- a/main.go
+++ b/main.go
@@ -2,11 +2,13 @@ package main
 
 import (
 	"context"
+	"flag"
 	"fmt"
 	"log"
 	"os"
 	"slices"
 	"sort"
+	"strconv"
 	"strings"
 	"sync"
 	"time"
@@ -34,6 +36,12 @@ type VersionPath struct {
 	Version        string
 }
 
+var userIdFlag = flag.String("user-id", "", "The Matrix user ID to use. (EnvVar: MRVC_USER_ID)")
+var tokenFlag = flag.String("token", "", "The Matrix access token to use. (EnvVar: MRVC_TOKEN)")
+var roomFlag = flag.String("room", "", "The Matrix room to check. (EnvVar: MRVC_ROOM)")
+var printHomeserverMemberCountFlag = flag.Bool("print-homeserver-member-count", false, "Print the member count for each homeserver. (EnvVar: MRVC_PRINT_HOMESERVER_MEMBER_COUNT)")
+var homeserverVersionInfoTimeoutFlag = flag.Duration("homeserver-version-info-timeout", time.Second*5, "Timeout for getting the homeservers version information per homeserver. (EnvVar: MRVC_HOMESERVER_VERSION_INFO_TIMEOUT)")
+
 var unknownServerVersionInfo = fclient.Version{
 	Server: struct {
 		Name    string `json:"name"`
@@ -281,11 +289,68 @@ func compareVersionStrings(a, b string) int {
 }
 
 func main() {
-	userIdString := os.Getenv("MATRIX_USER_ID")
-	token := os.Getenv("MATRIX_TOKEN")
-	room := os.Getenv("MATRIX_ROOM")
-	verbose := false
-	timeoutSeconds := 5
+	flag.Parse()
+
+	// Configuration variables.
+	var userIdString, token, room string
+	var printHomeserverMemberCount bool
+	var homeserverVersionInfoTimeout time.Duration
+
+	visitedFlags := make(map[string]bool)
+	flag.Visit(func(visitedFlag *flag.Flag) {
+		visitedFlags[visitedFlag.Name] = true
+	})
+
+	// Assign flag and environment variable values to configuration variables.
+	// Flags take precedence over environment variables.
+	// This also ensures some configuration options got explicitly set.
+	if visitedFlags["user-id"] {
+		userIdString = *userIdFlag
+	} else if userIdEnvVar, ok := os.LookupEnv("MRVC_USER_ID"); ok {
+		userIdString = userIdEnvVar
+	} else {
+		log.Fatal("A Matrix user ID must be provided.")
+	}
+	if visitedFlags["token"] {
+		token = *tokenFlag
+	} else if tokenEnvVar, ok := os.LookupEnv("MRVC_TOKEN"); ok {
+		token = tokenEnvVar
+	} else {
+		log.Fatal("A Matrix access token must be provided.")
+	}
+	if visitedFlags["room"] {
+		room = *roomFlag
+	} else if roomEnvVar, ok := os.LookupEnv("MRVC_ROOM"); ok {
+		room = roomEnvVar
+	} else {
+		log.Fatal("A Matrix room must be provided.")
+	}
+	if visitedFlags["print-homeserver-member-count"] {
+		printHomeserverMemberCount = *printHomeserverMemberCountFlag
+	} else if printHomeserverMemberCountEnvVar, ok := os.LookupEnv("MRVC_PRINT_HOMESERVER_MEMBER_COUNT"); ok {
+		parsedPrintHomeserverMemberCountEnvVar, err := strconv.ParseBool(printHomeserverMemberCountEnvVar)
+		if err != nil {
+			log.Println("Error parsing MRVC_PRINT_HOMESERVER_MEMBER_COUNT:")
+			log.Fatal(err)
+		}
+		printHomeserverMemberCount = parsedPrintHomeserverMemberCountEnvVar
+	} else {
+		// The flag holds the default value.
+		printHomeserverMemberCount = *printHomeserverMemberCountFlag
+	}
+	if visitedFlags["homeserver-version-info-timeout"] {
+		homeserverVersionInfoTimeout = *homeserverVersionInfoTimeoutFlag
+	} else if homeserverVersionInfoTimeoutEnvVar, ok := os.LookupEnv("MRVC_HOMESERVER_VERSION_INFO_TIMEOUT"); ok {
+		parsedHomeserverVersionInfoTimeoutEnvVar, err := time.ParseDuration(homeserverVersionInfoTimeoutEnvVar)
+		if err != nil {
+			log.Println("Error parsing MRVC_HOMESERVER_VERSION_INFO_TIMEOUT:")
+			log.Fatal(err)
+		}
+		homeserverVersionInfoTimeout = parsedHomeserverVersionInfoTimeoutEnvVar
+	} else {
+		// The flag holds the default value.
+		homeserverVersionInfoTimeout = *homeserverVersionInfoTimeoutFlag
+	}
 
 	userId := id.UserID(userIdString)
 	_, homeserver, err := userId.ParseAndValidate()
@@ -302,7 +367,7 @@ func main() {
 	}
 	federationClient := fclient.NewClient(
 		fclient.WithWellKnownSRVLookups(true),
-		fclient.WithTimeout(time.Second*time.Duration(timeoutSeconds)),
+		fclient.WithTimeout(homeserverVersionInfoTimeout),
 	)
 
 	joinedMembers, err := client.JoinedMembers(context.Background(), id.RoomID(room))
@@ -393,7 +458,7 @@ func main() {
 
 				fmt.Printf("    %s -> %d\n", versionKey, membersByVersionPath[VersionPath{maxRoomVersionKey, serverKey, versionKey}])
 
-				if verbose {
+				if printHomeserverMemberCount {
 					homeserverKeys := make([]string, 0, len(versionValue))
 					for key := range versionValue {
 						homeserverKeys = append(homeserverKeys, key)