diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index bb0a0a9..55d4b6f 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -32,9 +32,12 @@ jobs:
       - name: Build
         run: nix develop .#${{ matrix.rust }} --command cargo build --verbose
 
-      - name: Run tests
+      - name: Run cargo tests
         run: nix develop .#${{ matrix.rust }} --command cargo test --verbose
 
+      - name: Run integration tests
+        run: nix develop .#${{ matrix.rust }} --command tests/integration.sh
+
       - name: Check formatting
         run: nix develop .#${{ matrix.rust }} --command cargo fmt --check
 
diff --git a/tests/integration.sh b/tests/integration.sh
index 57dcde2..62d5f3a 100755
--- a/tests/integration.sh
+++ b/tests/integration.sh
@@ -1,104 +1,451 @@
 #!/usr/bin/env bash
 
-set -eExuo pipefail
+set -eEuo pipefail -o errtrace
 
-if ! command -v "pkill" >/dev/null 2>&1; then
-    printf "error: pkill not installed\n"
-    exit 1
+# Colors for output (disabled if no TTY or NO_COLOR set)
+if [[ ! -t 1 ]] || [[ -n "${NO_COLOR:-}" ]]; then
+    RED=""
+    GREEN=""
+    YELLOW=""
+    BLUE=""
+    NC=""
+else
+    RED='\033[0;31m'
+    GREEN='\033[0;32m'
+    YELLOW='\033[1;33m'
+    BLUE='\033[0;34m'
+    NC='\033[0m'
 fi
 
-python3 -V
+# Test tracking
+TESTS_RUN=0
+TESTS_PASSED=0
+TESTS_FAILED=0
 
-ASCIINEMA_CONFIG_HOME="$(
-    mktemp -d 2>/dev/null || mktemp -d -t asciinema-config-home
-)"
-
-export ASCIINEMA_CONFIG_HOME
-
-TMP_DATA_DIR="$(mktemp -d 2>/dev/null || mktemp -d -t asciinema-data-dir)"
-
-trap 'rm -rf ${ASCIINEMA_CONFIG_HOME} ${TMP_DATA_DIR}' EXIT
-
-asciinema() {
-    python3 -m asciinema "${@}"
+# Helper functions
+log_info() {
+    printf "%b\n" "${BLUE}INFO:${NC} $*"
 }
 
-## disable notifications
+log_success() {
+    printf "%b\n" "${GREEN}PASS:${NC} $*"
+    ((TESTS_PASSED++))
+}
 
-printf "[notifications]\nenabled = no\n" >> "${ASCIINEMA_CONFIG_HOME}/config"
+log_error() {
+    printf "%b\n" "${RED}FAIL:${NC} $*"
+    ((TESTS_FAILED++))
+}
 
-## test help message
+log_warning() {
+    printf "%b\n" "${YELLOW}WARN:${NC} $*"
+}
 
-asciinema -h
+assert_exit_code() {
+    local expected=$1
+    local actual=$2
+    local test_name=$3
+    
+    ((TESTS_RUN++))
+    if [[ $actual -eq $expected ]]; then
+        log_success "$test_name - exit code $actual"
+    else
+        log_error "$test_name - expected exit code $expected, got $actual"
+        return 1
+    fi
+}
 
-## test version command
+assert_file_exists() {
+    local file=$1
+    local test_name=$2
+    
+    ((TESTS_RUN++))
+    if [[ -f "$file" ]]; then
+        log_success "$test_name - file exists: $file"
+    else
+        log_error "$test_name - file does not exist: $file"
+        return 1
+    fi
+}
 
-asciinema --version
+assert_file_not_empty() {
+    local file=$1
+    local test_name=$2
+    
+    ((TESTS_RUN++))
+    if [[ -s "$file" ]]; then
+        log_success "$test_name - file not empty: $file"
+    else
+        log_error "$test_name - file is empty: $file"
+        return 1
+    fi
+}
 
-## test auth command
+assert_output_contains() {
+    local expected=$1
+    local output=$2
+    local test_name=$3
+    
+    ((TESTS_RUN++))
+    if echo "$output" | grep -q "$expected"; then
+        log_success "$test_name - output contains: $expected"
+    else
+        log_error "$test_name - output missing: $expected"
+        log_error "Actual output: $output"
+        return 1
+    fi
+}
 
-asciinema auth
+assert_file_contains() {
+    local expected=$1
+    local file=$2
+    local test_name=$3
+    
+    ((TESTS_RUN++))
+    if grep -q "$expected" "$file"; then
+        log_success "$test_name - file contains: $expected"
+    else
+        log_error "$test_name - file missing: $expected"
+        return 1
+    fi
+}
 
-## test play command
+# SETUP
+setup() {
+    log_info "Setting up test environment..."
+    
+    ASCIINEMA_CONFIG_HOME="$(
+        mktemp -d 2>/dev/null || mktemp -d -t asciinema-config-home
+    )"
 
-# asciicast v1
-asciinema play -s 5 tests/demo.json
-asciinema play -s 5 -i 0.2 tests/demo.json
-# shellcheck disable=SC2002
-cat tests/demo.json | asciinema play -s 5 -
+    ASCIINEMA_STATE_HOME="$(
+        mktemp -d 2>/dev/null || mktemp -d -t asciinema-state-home
+    )"
 
-# asciicast v2
-asciinema play -s 5 tests/demo.cast
-asciinema play -s 5 -i 0.2 tests/demo.cast
-# shellcheck disable=SC2002
-cat tests/demo.cast | asciinema play -s 5 -
+    ASCIINEMA_GEN_DIR="$(
+        mktemp -d 2>/dev/null || mktemp -d -t asciinema-gen-dir
+    )"
 
-## test cat command
+    export ASCIINEMA_CONFIG_HOME ASCIINEMA_STATE_HOME ASCIINEMA_GEN_DIR
+    export ASCIINEMA_SERVER_URL=https://asciinema.example.com
 
-# asciicast v1
-asciinema cat tests/demo.json
-# shellcheck disable=SC2002
-cat tests/demo.json | asciinema cat -
+    TMP_DATA_DIR="$(mktemp -d 2>/dev/null || mktemp -d -t asciinema-data-dir)"
+    SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+    FIXTURES="$SCRIPT_DIR/casts"
+    ASCIINEMA_BIN="$SCRIPT_DIR/../target/release/asciinema"
 
-# asciicast v2
-asciinema cat tests/demo.cast
-# shellcheck disable=SC2002
-cat tests/demo.cast | asciinema cat -
+    trap 'cleanup' EXIT
 
-## test rec command
+    log_info "Building release binary..."
+    cargo build --release --locked
 
-# normal program
-asciinema rec -c 'bash -c "echo t3st; sleep 2; echo ok"' "${TMP_DATA_DIR}/1a.cast"
-grep '"o",' "${TMP_DATA_DIR}/1a.cast"
+    # disable notifications
+    printf "[notifications]\nenabled = false\n" >> "${ASCIINEMA_CONFIG_HOME}/config.toml"
+    
+    log_info "Setup complete"
+}
 
-# very quickly exiting program
-asciinema rec -c whoami "${TMP_DATA_DIR}/1b.cast"
-grep '"o",' "${TMP_DATA_DIR}/1b.cast"
+cleanup() {
+    log_info "Cleaning up..."
+    rm -rf "${ASCIINEMA_CONFIG_HOME:-}" "${ASCIINEMA_STATE_HOME:-}" "${ASCIINEMA_GEN_DIR:-}" "${TMP_DATA_DIR:-}"
+}
 
-# signal handling
-bash -c "sleep 1; pkill -28 -n -f 'm asciinema'" &
-asciinema rec -c 'bash -c "echo t3st; sleep 2; echo ok"' "${TMP_DATA_DIR}/2.cast"
+# Test runner function
+run_test() {
+    local test_name="$1"
+    shift
+    
+    if [[ -z "${TEST:-}" || "${TEST:-}" == "$test_name" ]]; then
+        echo
+        echo "#################### TEST $test_name ####################"
+        "$@" || true  # Don't exit on test failure
+    fi
+}
 
-bash -c "sleep 1; pkill -n -f 'bash -c echo t3st'" &
-asciinema rec -c 'bash -c "echo t3st; sleep 2; echo ok"' "${TMP_DATA_DIR}/3.cast"
+# TEST FUNCTIONS
 
-bash -c "sleep 1; pkill -9 -n -f 'bash -c echo t3st'" &
-asciinema rec -c 'bash -c "echo t3st; sleep 2; echo ok"' "${TMP_DATA_DIR}/4.cast"
+test_help() {
+    log_info "Testing help command..."
+    
+    # Test short help
+    local output rc
+    if output=$("$ASCIINEMA_BIN" -h 2>&1); then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "help short flag"
+    assert_output_contains "Terminal session recorder" "$output" "help content"
+    assert_output_contains "Commands:" "$output" "help shows commands"
+    
+    # Test long help
+    if output=$("$ASCIINEMA_BIN" --help 2>&1); then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "help long flag"
+    assert_output_contains "Terminal session recorder" "$output" "help content"
+    
+    # Test help subcommand
+    if output=$("$ASCIINEMA_BIN" help 2>&1); then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "help subcommand"
+    assert_output_contains "Terminal session recorder" "$output" "help subcommand content"
+}
 
-# with stdin recording
-echo "ls" | asciinema rec --stdin -c 'bash -c "sleep 1"' "${TMP_DATA_DIR}/5.cast"
-cat "${TMP_DATA_DIR}/5.cast"
-grep '"i", "ls\\n"' "${TMP_DATA_DIR}/5.cast"
-grep '"o",' "${TMP_DATA_DIR}/5.cast"
+test_version() {
+    log_info "Testing version command..."
+    
+    # Test short version
+    local output rc
+    if output=$("$ASCIINEMA_BIN" -V 2>&1); then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "version short flag"
+    assert_output_contains "asciinema" "$output" "version output format"
+    
+    # Test long version
+    if output=$("$ASCIINEMA_BIN" --version 2>&1); then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "version long flag"
+    assert_output_contains "asciinema" "$output" "version output format"
+}
 
-# raw output recording
-asciinema rec --raw -c 'bash -c "echo t3st; sleep 1; echo ok"' "${TMP_DATA_DIR}/6.raw"
+test_auth() {
+    log_info "Testing auth command..."
+    
+    # Test auth command (should handle offline gracefully)
+    local output rc
+    if output=$("$ASCIINEMA_BIN" auth 2>&1); then rc=0; else rc=$?; fi
+    
+    # Auth should complete without hanging and show expected message
+    assert_exit_code 0 "$rc" "auth"
+    assert_output_contains "Open the following URL in a web browser" "$output" "auth command output"
+}
 
-# appending to existing recording
-asciinema rec -c 'echo allright!; sleep 0.1' "${TMP_DATA_DIR}/7.cast"
-asciinema rec --append -c uptime "${TMP_DATA_DIR}/7.cast"
+test_record() {
+    log_info "Testing record command..."
+    
+    # Test basic recording
+    local file1="$TMP_DATA_DIR/record_basic.cast"
+    local rc
+    if "$ASCIINEMA_BIN" record --headless --command 'echo "hello world"' --return "$file1"; then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "record basic"
+    assert_file_contains '"o",' "$file1" "record output event"
+    assert_file_contains 'hello world' "$file1" "record output content"
+    
+    # Test different formats
+    local file2="$TMP_DATA_DIR/record_v2.cast"
+    if "$ASCIINEMA_BIN" record --headless --command 'echo "test v2"' --output-format asciicast-v2 --return "$file2"; then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "record v2 format"
+    assert_file_not_empty "$file2" "record v2 format"
+    
+    local file3="$TMP_DATA_DIR/record_v3.cast"
+    if "$ASCIINEMA_BIN" record --headless --command 'echo "test v3"' --output-format asciicast-v3 --return "$file3"; then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "record v3 format"
+    assert_file_not_empty "$file3" "record v3 format"
+    
+    # Test raw format
+    local file4="$TMP_DATA_DIR/record_raw.raw"
+    if "$ASCIINEMA_BIN" record --headless --command 'echo "test raw"' --output-format raw --return "$file4"; then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "record raw format"
+    assert_file_not_empty "$file4" "record raw format"
+    
+    # Test txt format
+    local file5="$TMP_DATA_DIR/record_txt.txt"
+    if "$ASCIINEMA_BIN" record --headless --command 'echo "test txt"' --output-format txt --return "$file5"; then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "record txt format"
+    assert_file_not_empty "$file5" "record txt format"
+    
+    # Test return flag with failure
+    local file6="$TMP_DATA_DIR/record_fail.cast"
+    if "$ASCIINEMA_BIN" record --headless --command 'exit 42' --return "$file6"; then rc=0; else rc=$?; fi
+    assert_exit_code 42 "$rc" "record return flag with failure"
+    assert_file_not_empty "$file6" "record failure"
+    
+    # Test append mode
+    local file7="$TMP_DATA_DIR/record_append.cast"
+    if "$ASCIINEMA_BIN" record --headless --command 'echo "first"' --return "$file7"; then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "record append setup"
+    if "$ASCIINEMA_BIN" record --headless --command 'echo "second"' --append --return "$file7"; then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "record append"
+    assert_file_contains 'first' "$file7" "record append first content"
+    assert_file_contains 'second' "$file7" "record append second content"
+    
+    # Test idle time limits
+    local file8="$TMP_DATA_DIR/record_idle.cast"
+    if "$ASCIINEMA_BIN" record --headless --command 'bash -c "echo start; sleep 2; echo end"' --idle-time-limit 1 --return "$file8"; then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "record idle time limit"
+    assert_file_not_empty "$file8" "record idle time limit"
+}
 
-# adding a marker
-printf "[record]\nadd_marker_key = C-b\n" >> "${ASCIINEMA_CONFIG_HOME}/config"
-(bash -c "sleep 1; printf '.'; sleep 0.5; printf '\x08'; sleep 0.5; printf '\x02'; sleep 0.5; printf '\x04'") | asciinema rec -c /bin/bash "${TMP_DATA_DIR}/8.cast"
-grep '"m",' "${TMP_DATA_DIR}/8.cast"
+test_stream() {
+    log_info "Testing stream command..."
+    
+    # Test local streaming
+    timeout 10s "$ASCIINEMA_BIN" stream --headless --local 127.0.0.1:8081 --command 'bash -c "echo streaming test; sleep 3; echo done"' --return &
+    local stream_pid=$!
+    
+    # Wait a moment for server to start
+    sleep 1
+    
+    # Test if HTTP server is responding and serving the player
+    local curl_output rc
+    if curl_output=$(curl -fsS "http://127.0.0.1:8081" 2>&1); then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "stream server responding"
+    assert_output_contains "AsciinemaPlayer" "$curl_output" "stream server AsciinemaPlayer content"
+    
+    # Clean up
+    kill $stream_pid 2>/dev/null || true
+    wait $stream_pid 2>/dev/null || true
+}
+
+test_session() {
+    log_info "Testing session command..."
+    
+    # Test session with file output
+    local file1="$TMP_DATA_DIR/session_basic.cast"
+    local rc
+    if "$ASCIINEMA_BIN" session --headless --output-file "$file1" --command 'echo "session test"' --return; then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "session basic"
+    assert_file_contains 'session test' "$file1" "session output content"
+    
+    # Test session with return flag failure
+    local file2="$TMP_DATA_DIR/session_fail.cast"
+    if "$ASCIINEMA_BIN" session --headless --output-file "$file2" --command 'exit 13' --return; then rc=0; else rc=$?; fi
+    assert_exit_code 13 "$rc" "session return flag with failure"
+    assert_file_contains '"x", "13"' "$file2" "session exit event"
+    
+    # Test session with local streaming + file output
+    local file3="$TMP_DATA_DIR/session_stream.cast"
+    timeout 8s "$ASCIINEMA_BIN" session --headless --output-file "$file3" --stream-local 127.0.0.1:8081 --command 'bash -c "echo stream session; sleep 3; echo done"' --return &
+    local session_pid=$!
+    
+    # Wait a moment for server to start
+    sleep 1
+    
+    # Test if both file and HTTP server work
+    local curl_output
+    if curl_output=$(curl -fsS "http://127.0.0.1:8081" 2>&1); then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "stream server responding"
+    assert_output_contains "AsciinemaPlayer" "$curl_output" "session streaming server AsciinemaPlayer content"
+    
+    # Clean up and check file
+    kill $session_pid 2>/dev/null || true
+    wait $session_pid 2>/dev/null || true
+    
+    if [[ -f "$file3" ]]; then
+        assert_file_contains 'stream session' "$file3" "session output content"
+    fi
+    
+    # Test different output formats
+    local file4="$TMP_DATA_DIR/session_v2.cast"
+    if "$ASCIINEMA_BIN" session --headless --output-file "$file4" --output-format asciicast-v2 --command 'echo "session v2"' --return; then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "session v2 format"
+    assert_file_contains 'session v2' "$file4" "session output content"
+    
+    # Test append mode
+    local file5="$TMP_DATA_DIR/session_append.cast"
+    if "$ASCIINEMA_BIN" session --headless --output-file "$file5" --command 'echo "first session"' --return; then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "session append setup"
+    if "$ASCIINEMA_BIN" session --headless --output-file "$file5" --append --command 'echo "second session"' --return; then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "session append"
+    assert_file_contains 'first session' "$file5" "session append first content"
+    assert_file_contains 'second session' "$file5" "session append second content"
+}
+
+test_cat() {
+    log_info "Testing cat command..."
+    
+    # Create test recordings first
+    local file1="$TMP_DATA_DIR/cat_input1.cast"
+    local file2="$TMP_DATA_DIR/cat_input2.cast"
+    local rc
+    
+    if "$ASCIINEMA_BIN" record --headless --command 'echo "first recording"' --return "$file1"; then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "cat setup first recording"
+    
+    if "$ASCIINEMA_BIN" record --headless --command 'echo "second recording"' --return "$file2"; then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "cat setup second recording"
+    
+    # Test concatenation to stdout
+    local output
+    if output=$("$ASCIINEMA_BIN" cat "$file1" "$file2" 2>&1); then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "cat concatenate"
+    assert_output_contains 'first recording' "$output" "cat first content"
+    assert_output_contains 'second recording' "$output" "cat second content"
+    
+    # Test with different format inputs (using fixtures, v2+v3 only since v1 can't be concatenated)
+    if output=$("$ASCIINEMA_BIN" cat "$FIXTURES/minimal-v2.cast" "$FIXTURES/minimal-v3.cast" 2>&1); then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "cat mixed formats"
+    assert_output_contains '"version":' "$output" "cat mixed formats output"
+}
+
+test_convert() {
+    log_info "Testing convert command..."
+    
+    # Test v1 to v3 conversion
+    local file1="$TMP_DATA_DIR/convert_v1_to_v3.cast"
+    local rc
+    if "$ASCIINEMA_BIN" convert "$FIXTURES/minimal-v1.json" "$file1"; then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "convert v1 to v3"
+    assert_file_contains '"version":3' "$file1" "convert v1 to v3 version"
+    
+    # Test v2 to v3 conversion
+    local file2="$TMP_DATA_DIR/convert_v2_to_v3.cast"
+    if "$ASCIINEMA_BIN" convert "$FIXTURES/minimal-v2.cast" "$file2"; then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "convert v2 to v3"
+    assert_file_contains '"version":3' "$file2" "convert v2 to v3 version"
+    
+    # Test to raw format
+    local file3="$TMP_DATA_DIR/convert_to_raw.raw"
+    if "$ASCIINEMA_BIN" convert --output-format raw "$FIXTURES/minimal-v2.cast" "$file3"; then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "convert to raw"
+    assert_file_exists "$file3" "convert to raw output"
+    
+    # Test to txt format
+    local file4="$TMP_DATA_DIR/convert_to_txt.txt"
+    if "$ASCIINEMA_BIN" convert --output-format txt "$FIXTURES/minimal-v2.cast" "$file4"; then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "convert to txt"
+    assert_file_exists "$file4" "convert to txt output"
+    
+    # Test output to stdout
+    local output
+    if output=$("$ASCIINEMA_BIN" convert "$FIXTURES/minimal-v2.cast" - 2>&1); then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "convert to stdout"
+    assert_output_contains '"version":3' "$output" "convert stdout version"
+    
+    # Test overwrite behavior
+    local file5="$TMP_DATA_DIR/convert_overwrite.cast"
+    echo "existing content" > "$file5"
+    if "$ASCIINEMA_BIN" convert --overwrite "$FIXTURES/minimal-v2.cast" "$file5"; then rc=0; else rc=$?; fi
+    assert_exit_code 0 "$rc" "convert overwrite"
+    assert_file_contains '"version":3' "$file5" "convert overwrite content"
+}
+
+# MAIN EXECUTION
+
+# Setup always runs
+setup
+
+echo
+echo "######################################################"
+echo "# ASCIINEMA CLI INTEGRATION TESTS"
+echo "######################################################"
+echo "# Test filter: ${TEST:-ALL}"
+echo "######################################################"
+
+# Individual test blocks
+run_test "help" test_help
+run_test "version" test_version
+run_test "auth" test_auth
+run_test "record" test_record
+run_test "stream" test_stream
+run_test "session" test_session
+run_test "cat" test_cat
+run_test "convert" test_convert
+
+# Final summary
+echo
+echo "######################################################"
+echo "# TEST SUMMARY"
+echo "######################################################"
+echo "Tests run: $TESTS_RUN"
+printf "%bTests passed: %b%s%b\n" "" "${GREEN}" "$TESTS_PASSED" "${NC}"
+if [[ $TESTS_FAILED -gt 0 ]]; then
+    printf "%bTests failed: %b%s%b\n" "" "${RED}" "$TESTS_FAILED" "${NC}"
+    echo "OVERALL RESULT: FAILED"
+    exit 1
+else
+    printf "%bTests failed: %b%s%b\n" "" "${GREEN}" "0" "${NC}"
+    echo "OVERALL RESULT: SUCCESS"
+fi