diff --git a/components/engine/client/client.go b/components/engine/client/client.go
index ab208c319b..240e32ae05 100644
--- a/components/engine/client/client.go
+++ b/components/engine/client/client.go
@@ -107,8 +107,14 @@ func CheckRedirect(req *http.Request, via []*http.Request) error {
 // Use DOCKER_API_VERSION to set the version of the API to reach, leave empty for latest.
 // Use DOCKER_CERT_PATH to load the TLS certificates from.
 // Use DOCKER_TLS_VERIFY to enable or disable TLS verification, off by default.
+// deprecated: use NewClientWithOpts(FromEnv)
 func NewEnvClient() (*Client, error) {
-	var client *http.Client
+	return NewClientWithOpts(FromEnv)
+}
+
+// FromEnv enhance the default client with values from environment variables
+func FromEnv(c *Client) error {
+	var httpClient *http.Client
 	if dockerCertPath := os.Getenv("DOCKER_CERT_PATH"); dockerCertPath != "" {
 		options := tlsconfig.Options{
 			CAFile:             filepath.Join(dockerCertPath, "ca.pem"),
@@ -118,10 +124,10 @@ func NewEnvClient() (*Client, error) {
 		}
 		tlsc, err := tlsconfig.Client(options)
 		if err != nil {
-			return nil, err
+			return err
 		}
 
-		client = &http.Client{
+		httpClient = &http.Client{
 			Transport: &http.Transport{
 				TLSClientConfig: tlsc,
 			},
@@ -130,22 +136,128 @@ func NewEnvClient() (*Client, error) {
 	}
 
 	host := os.Getenv("DOCKER_HOST")
-	if host == "" {
-		host = DefaultDockerHost
+	if host != "" {
+		var err error
+		if err := WithHost(host)(c); err != nil {
+			return err
+		}
+		httpClient, err = defaultHTTPClient(host)
+		if err != nil {
+			return err
+		}
+	}
+	if httpClient != nil {
+		if err := WithHTTPClient(httpClient)(c); err != nil {
+			return err
+		}
 	}
 	version := os.Getenv("DOCKER_API_VERSION")
-	if version == "" {
-		version = api.DefaultVersion
+	if version != "" {
+		c.version = version
+		c.manualOverride = true
+	}
+	return nil
+}
+
+// WithVersion overrides the client version with the specified one
+func WithVersion(version string) func(*Client) error {
+	return func(c *Client) error {
+		c.version = version
+		return nil
+	}
+}
+
+// WithHost overrides the client host with the specified one
+func WithHost(host string) func(*Client) error {
+	return func(c *Client) error {
+		hostURL, err := ParseHostURL(host)
+		if err != nil {
+			return err
+		}
+		c.host = host
+		c.proto = hostURL.Scheme
+		c.addr = hostURL.Host
+		c.basePath = hostURL.Path
+		client, err := defaultHTTPClient(host)
+		if err != nil {
+			return err
+		}
+		return WithHTTPClient(client)(c)
+	}
+}
+
+// WithHTTPClient overrides the client http client with the specified one
+func WithHTTPClient(client *http.Client) func(*Client) error {
+	return func(c *Client) error {
+		if client != nil {
+			c.client = client
+		}
+		return nil
+	}
+}
+
+// WithHTTPHeaders overrides the client default http headers
+func WithHTTPHeaders(headers map[string]string) func(*Client) error {
+	return func(c *Client) error {
+		c.customHTTPHeaders = headers
+		return nil
+	}
+}
+
+// NewClientWithOpts initializes a new API client with default values. It takes functors
+// to modify values when creating it, like `NewClientWithOpts(WithVersion(…))`
+// It also initializes the custom http headers to add to each request.
+//
+// It won't send any version information if the version number is empty. It is
+// highly recommended that you set a version or your client may break if the
+// server is upgraded.
+func NewClientWithOpts(ops ...func(*Client) error) (*Client, error) {
+	client, err := defaultHTTPClient(DefaultDockerHost)
+	if err != nil {
+		return nil, err
+	}
+	c := &Client{
+		host:    DefaultDockerHost,
+		version: api.DefaultVersion,
+		scheme:  "http",
+		client:  client,
+		proto:   defaultProto,
+		addr:    defaultAddr,
 	}
 
-	cli, err := NewClient(host, version, client, nil)
+	for _, op := range ops {
+		if err := op(c); err != nil {
+			return nil, err
+		}
+	}
+
+	if _, ok := c.client.Transport.(http.RoundTripper); !ok {
+		return nil, fmt.Errorf("unable to verify TLS configuration, invalid transport %v", c.client.Transport)
+	}
+	tlsConfig := resolveTLSConfig(c.client.Transport)
+	if tlsConfig != nil {
+		// TODO(stevvooe): This isn't really the right way to write clients in Go.
+		// `NewClient` should probably only take an `*http.Client` and work from there.
+		// Unfortunately, the model of having a host-ish/url-thingy as the connection
+		// string has us confusing protocol and transport layers. We continue doing
+		// this to avoid breaking existing clients but this should be addressed.
+		c.scheme = "https"
+	}
+
+	return c, nil
+}
+
+func defaultHTTPClient(host string) (*http.Client, error) {
+	url, err := ParseHostURL(host)
 	if err != nil {
-		return cli, err
+		return nil, err
 	}
-	if os.Getenv("DOCKER_API_VERSION") != "" {
-		cli.manualOverride = true
-	}
-	return cli, nil
+	transport := new(http.Transport)
+	sockets.ConfigureTransport(transport, url.Scheme, url.Host)
+	return &http.Client{
+		Transport:     transport,
+		CheckRedirect: CheckRedirect,
+	}, nil
 }
 
 // NewClient initializes a new API client for the given host and API version.
@@ -155,47 +267,9 @@ func NewEnvClient() (*Client, error) {
 // It won't send any version information if the version number is empty. It is
 // highly recommended that you set a version or your client may break if the
 // server is upgraded.
+// deprecated: use NewClientWithOpts
 func NewClient(host string, version string, client *http.Client, httpHeaders map[string]string) (*Client, error) {
-	hostURL, err := ParseHostURL(host)
-	if err != nil {
-		return nil, err
-	}
-
-	if client != nil {
-		if _, ok := client.Transport.(http.RoundTripper); !ok {
-			return nil, fmt.Errorf("unable to verify TLS configuration, invalid transport %v", client.Transport)
-		}
-	} else {
-		transport := new(http.Transport)
-		sockets.ConfigureTransport(transport, hostURL.Scheme, hostURL.Host)
-		client = &http.Client{
-			Transport:     transport,
-			CheckRedirect: CheckRedirect,
-		}
-	}
-
-	scheme := "http"
-	tlsConfig := resolveTLSConfig(client.Transport)
-	if tlsConfig != nil {
-		// TODO(stevvooe): This isn't really the right way to write clients in Go.
-		// `NewClient` should probably only take an `*http.Client` and work from there.
-		// Unfortunately, the model of having a host-ish/url-thingy as the connection
-		// string has us confusing protocol and transport layers. We continue doing
-		// this to avoid breaking existing clients but this should be addressed.
-		scheme = "https"
-	}
-
-	// TODO: store URL instead of proto/addr/basePath
-	return &Client{
-		scheme:            scheme,
-		host:              host,
-		proto:             hostURL.Scheme,
-		addr:              hostURL.Host,
-		basePath:          hostURL.Path,
-		client:            client,
-		version:           version,
-		customHTTPHeaders: httpHeaders,
-	}, nil
+	return NewClientWithOpts(WithHost(host), WithVersion(version), WithHTTPClient(client), WithHTTPHeaders(httpHeaders))
 }
 
 // Close the transport used by the client
diff --git a/components/engine/client/client_unix.go b/components/engine/client/client_unix.go
index c5e887e277..3d24470ba3 100644
--- a/components/engine/client/client_unix.go
+++ b/components/engine/client/client_unix.go
@@ -4,3 +4,6 @@ package client // import "github.com/docker/docker/client"
 
 // DefaultDockerHost defines os specific default if DOCKER_HOST is unset
 const DefaultDockerHost = "unix:///var/run/docker.sock"
+
+const defaultProto = "unix"
+const defaultAddr = "/var/run/docker.sock"
diff --git a/components/engine/client/client_windows.go b/components/engine/client/client_windows.go
index 45d8c7c9e6..c649e54412 100644
--- a/components/engine/client/client_windows.go
+++ b/components/engine/client/client_windows.go
@@ -2,3 +2,6 @@ package client // import "github.com/docker/docker/client"
 
 // DefaultDockerHost defines os specific default if DOCKER_HOST is unset
 const DefaultDockerHost = "npipe:////./pipe/docker_engine"
+
+const defaultProto = "npipe"
+const defaultAddr = "//./pipe/docker_engine"
diff --git a/components/engine/integration-cli/daemon/daemon.go b/components/engine/integration-cli/daemon/daemon.go
index 149d775fea..69a87d9d9c 100644
--- a/components/engine/integration-cli/daemon/daemon.go
+++ b/components/engine/integration-cli/daemon/daemon.go
@@ -566,7 +566,7 @@ func (d *Daemon) WaitRun(contID string) error {
 
 // Info returns the info struct for this daemon
 func (d *Daemon) Info(t require.TestingT) types.Info {
-	apiclient, err := request.NewClientForHost(d.Sock())
+	apiclient, err := client.NewClientWithOpts(client.WithHost((d.Sock())))
 	require.NoError(t, err)
 	info, err := apiclient.Info(context.Background())
 	require.NoError(t, err)
diff --git a/components/engine/integration-cli/docker_api_containers_test.go b/components/engine/integration-cli/docker_api_containers_test.go
index 02e8e9f7d2..a91c91abe5 100644
--- a/components/engine/integration-cli/docker_api_containers_test.go
+++ b/components/engine/integration-cli/docker_api_containers_test.go
@@ -1372,7 +1372,8 @@ func (s *DockerSuite) TestContainerAPICreateNoHostConfig118(c *check.C) {
 		Image: "busybox",
 	}
 
-	cli, err := request.NewEnvClientWithVersion("v1.18")
+	cli, err := client.NewClientWithOpts(client.FromEnv, client.WithVersion("v1.18"))
+	c.Assert(err, checker.IsNil)
 
 	_, err = cli.ContainerCreate(context.Background(), &config, &containertypes.HostConfig{}, &networktypes.NetworkingConfig{}, "")
 	c.Assert(err, checker.IsNil)
diff --git a/components/engine/integration-cli/docker_api_images_test.go b/components/engine/integration-cli/docker_api_images_test.go
index 10cb52eeb0..a5628e41b9 100644
--- a/components/engine/integration-cli/docker_api_images_test.go
+++ b/components/engine/integration-cli/docker_api_images_test.go
@@ -179,7 +179,7 @@ func (s *DockerSuite) TestAPIImagesSizeCompatibility(c *check.C) {
 		Labels      map[string]string
 	}
 
-	cli, err = request.NewEnvClientWithVersion("v1.24")
+	cli, err = client.NewClientWithOpts(client.FromEnv, client.WithVersion("v1.24"))
 	c.Assert(err, checker.IsNil)
 	defer cli.Close()
 
diff --git a/components/engine/integration-cli/docker_api_inspect_unix_test.go b/components/engine/integration-cli/docker_api_inspect_unix_test.go
index dae64be2a7..17844e0bfc 100644
--- a/components/engine/integration-cli/docker_api_inspect_unix_test.go
+++ b/components/engine/integration-cli/docker_api_inspect_unix_test.go
@@ -5,8 +5,8 @@ package main
 import (
 	"encoding/json"
 
+	"github.com/docker/docker/client"
 	"github.com/docker/docker/integration-cli/checker"
-	"github.com/docker/docker/integration-cli/request"
 	"github.com/go-check/check"
 	"golang.org/x/net/context"
 )
@@ -18,7 +18,7 @@ func (s *DockerSuite) TestInspectAPICpusetInConfigPre120(c *check.C) {
 
 	name := "cpusetinconfig-pre120"
 	dockerCmd(c, "run", "--name", name, "--cpuset-cpus", "0", "busybox", "true")
-	cli, err := request.NewEnvClientWithVersion("v1.19")
+	cli, err := client.NewClientWithOpts(client.FromEnv, client.WithVersion("v1.19"))
 	c.Assert(err, checker.IsNil)
 	defer cli.Close()
 	_, body, err := cli.ContainerInspectWithRaw(context.Background(), name, false)
diff --git a/components/engine/integration-cli/docker_cli_kill_test.go b/components/engine/integration-cli/docker_cli_kill_test.go
index 0a5aac5f8c..e2e510fcaa 100644
--- a/components/engine/integration-cli/docker_cli_kill_test.go
+++ b/components/engine/integration-cli/docker_cli_kill_test.go
@@ -6,37 +6,9 @@ import (
 
 	"github.com/docker/docker/integration-cli/checker"
 	"github.com/docker/docker/integration-cli/cli"
-	"github.com/docker/docker/integration-cli/request"
 	"github.com/go-check/check"
-	"github.com/gotestyourself/gotestyourself/icmd"
-	"golang.org/x/net/context"
 )
 
-func (s *DockerSuite) TestKillContainer(c *check.C) {
-	out := runSleepingContainer(c, "-d")
-	cleanedContainerID := strings.TrimSpace(out)
-	cli.WaitRun(c, cleanedContainerID)
-
-	cli.DockerCmd(c, "kill", cleanedContainerID)
-	cli.WaitExited(c, cleanedContainerID, 10*time.Second)
-
-	out = cli.DockerCmd(c, "ps", "-q").Combined()
-	c.Assert(out, checker.Not(checker.Contains), cleanedContainerID, check.Commentf("killed container is still running"))
-
-}
-
-func (s *DockerSuite) TestKillOffStoppedContainer(c *check.C) {
-	out := runSleepingContainer(c, "-d")
-	cleanedContainerID := strings.TrimSpace(out)
-
-	cli.DockerCmd(c, "stop", cleanedContainerID)
-	cli.WaitExited(c, cleanedContainerID, 10*time.Second)
-
-	cli.Docker(cli.Args("kill", "-s", "30", cleanedContainerID)).Assert(c, icmd.Expected{
-		ExitCode: 1,
-	})
-}
-
 func (s *DockerSuite) TestKillDifferentUserContainer(c *check.C) {
 	// TODO Windows: Windows does not yet support -u (Feb 2016).
 	testRequires(c, DaemonIsLinux)
@@ -51,88 +23,3 @@ func (s *DockerSuite) TestKillDifferentUserContainer(c *check.C) {
 	c.Assert(out, checker.Not(checker.Contains), cleanedContainerID, check.Commentf("killed container is still running"))
 
 }
-
-// regression test about correct signal parsing see #13665
-func (s *DockerSuite) TestKillWithSignal(c *check.C) {
-	// Cannot port to Windows - does not support signals in the same way Linux does
-	testRequires(c, DaemonIsLinux)
-	out, _ := dockerCmd(c, "run", "-d", "busybox", "top")
-	cid := strings.TrimSpace(out)
-	c.Assert(waitRun(cid), check.IsNil)
-
-	dockerCmd(c, "kill", "-s", "SIGWINCH", cid)
-	time.Sleep(250 * time.Millisecond)
-
-	running := inspectField(c, cid, "State.Running")
-
-	c.Assert(running, checker.Equals, "true", check.Commentf("Container should be in running state after SIGWINCH"))
-}
-
-func (s *DockerSuite) TestKillWithStopSignalWithSameSignalShouldDisableRestartPolicy(c *check.C) {
-	// Cannot port to Windows - does not support signals int the same way as Linux does
-	testRequires(c, DaemonIsLinux)
-	out := cli.DockerCmd(c, "run", "-d", "--stop-signal=TERM", "--restart=always", "busybox", "top").Combined()
-	cid := strings.TrimSpace(out)
-	cli.WaitRun(c, cid)
-
-	// Let docker send a TERM signal to the container
-	// It will kill the process and disable the restart policy
-	cli.DockerCmd(c, "kill", "-s", "TERM", cid)
-	cli.WaitExited(c, cid, 10*time.Second)
-
-	out = cli.DockerCmd(c, "ps", "-q").Combined()
-	c.Assert(out, checker.Not(checker.Contains), cid, check.Commentf("killed container is still running"))
-}
-
-func (s *DockerSuite) TestKillWithStopSignalWithDifferentSignalShouldKeepRestartPolicy(c *check.C) {
-	// Cannot port to Windows - does not support signals int the same way as Linux does
-	testRequires(c, DaemonIsLinux)
-	out := cli.DockerCmd(c, "run", "-d", "--stop-signal=CONT", "--restart=always", "busybox", "top").Combined()
-	cid := strings.TrimSpace(out)
-	cli.WaitRun(c, cid)
-
-	// Let docker send a TERM signal to the container
-	// It will kill the process, but not disable the restart policy
-	cli.DockerCmd(c, "kill", "-s", "TERM", cid)
-	cli.WaitRestart(c, cid, 10*time.Second)
-
-	// Restart policy should still be in place, so it should be still running
-	cli.WaitRun(c, cid)
-}
-
-// FIXME(vdemeester) should be a unit test
-func (s *DockerSuite) TestKillWithInvalidSignal(c *check.C) {
-	out := runSleepingContainer(c, "-d")
-	cid := strings.TrimSpace(out)
-	c.Assert(waitRun(cid), check.IsNil)
-
-	out, _, err := dockerCmdWithError("kill", "-s", "0", cid)
-	c.Assert(err, check.NotNil)
-	c.Assert(out, checker.Contains, "Invalid signal: 0", check.Commentf("Kill with an invalid signal didn't error out correctly"))
-
-	running := inspectField(c, cid, "State.Running")
-	c.Assert(running, checker.Equals, "true", check.Commentf("Container should be in running state after an invalid signal"))
-
-	out = runSleepingContainer(c, "-d")
-	cid = strings.TrimSpace(out)
-	c.Assert(waitRun(cid), check.IsNil)
-
-	out, _, err = dockerCmdWithError("kill", "-s", "SIG42", cid)
-	c.Assert(err, check.NotNil)
-	c.Assert(out, checker.Contains, "Invalid signal: SIG42", check.Commentf("Kill with an invalid signal error out correctly"))
-
-	running = inspectField(c, cid, "State.Running")
-	c.Assert(running, checker.Equals, "true", check.Commentf("Container should be in running state after an invalid signal"))
-
-}
-
-func (s *DockerSuite) TestKillStoppedContainerAPIPre120(c *check.C) {
-	testRequires(c, DaemonIsLinux) // Windows only supports 1.25 or later
-	runSleepingContainer(c, "--name", "docker-kill-test-api", "-d")
-	dockerCmd(c, "stop", "docker-kill-test-api")
-	cli, err := request.NewEnvClientWithVersion("v1.19")
-	c.Assert(err, check.IsNil)
-	defer cli.Close()
-	err = cli.ContainerKill(context.Background(), "docker-kill-test-api", "SIGKILL")
-	c.Assert(err, check.IsNil)
-}
diff --git a/components/engine/integration-cli/docker_utils_test.go b/components/engine/integration-cli/docker_utils_test.go
index 6eda88c684..ea780cc6e8 100644
--- a/components/engine/integration-cli/docker_utils_test.go
+++ b/components/engine/integration-cli/docker_utils_test.go
@@ -372,7 +372,7 @@ func waitInspectWithArgs(name, expr, expected string, timeout time.Duration, arg
 }
 
 func getInspectBody(c *check.C, version, id string) []byte {
-	cli, err := request.NewEnvClientWithVersion(version)
+	cli, err := client.NewClientWithOpts(client.FromEnv, client.WithVersion(version))
 	c.Assert(err, check.IsNil)
 	defer cli.Close()
 	_, body, err := cli.ContainerInspectWithRaw(context.Background(), id, false)
diff --git a/components/engine/integration-cli/request/request.go b/components/engine/integration-cli/request/request.go
index a937708665..e4a1e3e892 100644
--- a/components/engine/integration-cli/request/request.go
+++ b/components/engine/integration-cli/request/request.go
@@ -17,7 +17,6 @@ import (
 	"strings"
 	"time"
 
-	"github.com/docker/docker/api"
 	dclient "github.com/docker/docker/client"
 	"github.com/docker/docker/opts"
 	"github.com/docker/docker/pkg/ioutils"
@@ -169,16 +168,7 @@ func NewHTTPClient(host string) (*http.Client, error) {
 
 // NewClient returns a new Docker API client
 func NewClient() (dclient.APIClient, error) {
-	return NewClientForHost(DaemonHost())
-}
-
-// NewClientForHost returns a Docker API client for the host
-func NewClientForHost(host string) (dclient.APIClient, error) {
-	httpClient, err := NewHTTPClient(host)
-	if err != nil {
-		return nil, err
-	}
-	return dclient.NewClient(host, api.DefaultVersion, httpClient, nil)
+	return dclient.NewClientWithOpts(dclient.WithHost(DaemonHost()))
 }
 
 // FIXME(vdemeester) httputil.ClientConn is deprecated, use http.Client instead (closer to actual client)
@@ -323,35 +313,3 @@ func DaemonHost() string {
 	}
 	return daemonURLStr
 }
-
-// NewEnvClientWithVersion returns a docker client with a specified version.
-// See: github.com/docker/docker/client `NewEnvClient()`
-func NewEnvClientWithVersion(version string) (*dclient.Client, error) {
-	if version == "" {
-		return nil, errors.New("version not specified")
-	}
-
-	var httpClient *http.Client
-	if os.Getenv("DOCKER_CERT_PATH") != "" {
-		tlsConfig, err := getTLSConfig()
-		if err != nil {
-			return nil, err
-		}
-		httpClient = &http.Client{
-			Transport: &http.Transport{
-				TLSClientConfig: tlsConfig,
-			},
-		}
-	}
-
-	host := os.Getenv("DOCKER_HOST")
-	if host == "" {
-		host = dclient.DefaultDockerHost
-	}
-
-	cli, err := dclient.NewClient(host, version, httpClient, nil)
-	if err != nil {
-		return cli, err
-	}
-	return cli, nil
-}
diff --git a/components/engine/integration/container/kill_test.go b/components/engine/integration/container/kill_test.go
new file mode 100644
index 0000000000..57343942da
--- /dev/null
+++ b/components/engine/integration/container/kill_test.go
@@ -0,0 +1,177 @@
+package container
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/api/types/container"
+	"github.com/docker/docker/api/types/network"
+	"github.com/docker/docker/api/types/strslice"
+	"github.com/docker/docker/client"
+	"github.com/docker/docker/integration/util/request"
+	"github.com/gotestyourself/gotestyourself/poll"
+	"github.com/gotestyourself/gotestyourself/skip"
+	"github.com/stretchr/testify/require"
+)
+
+func TestKillContainerInvalidSignal(t *testing.T) {
+	defer setupTest(t)()
+	client := request.NewAPIClient(t)
+	ctx := context.Background()
+	c, err := client.ContainerCreate(ctx,
+		&container.Config{
+			Image: "busybox",
+			Cmd:   strslice.StrSlice([]string{"top"}),
+		},
+		&container.HostConfig{},
+		&network.NetworkingConfig{},
+		"")
+	require.NoError(t, err)
+	err = client.ContainerStart(ctx, c.ID, types.ContainerStartOptions{})
+	require.NoError(t, err)
+
+	err = client.ContainerKill(ctx, c.ID, "0")
+	require.EqualError(t, err, "Error response from daemon: Invalid signal: 0")
+	poll.WaitOn(t, containerIsInState(ctx, client, c.ID, "running"), poll.WithDelay(100*time.Millisecond))
+
+	err = client.ContainerKill(ctx, c.ID, "SIG42")
+	require.EqualError(t, err, "Error response from daemon: Invalid signal: SIG42")
+	poll.WaitOn(t, containerIsInState(ctx, client, c.ID, "running"), poll.WithDelay(100*time.Millisecond))
+}
+
+func TestKillContainer(t *testing.T) {
+	defer setupTest(t)()
+	client := request.NewAPIClient(t)
+
+	testCases := []struct {
+		doc    string
+		signal string
+		status string
+	}{
+		{
+			doc:    "no signal",
+			signal: "",
+			status: "exited",
+		},
+		{
+			doc:    "non killing signal",
+			signal: "SIGWINCH",
+			status: "running",
+		},
+		{
+			doc:    "killing signal",
+			signal: "SIGTERM",
+			status: "exited",
+		},
+	}
+
+	for _, tc := range testCases {
+		tc := tc
+		t.Run(tc.doc, func(t *testing.T) {
+			ctx := context.Background()
+			c, err := client.ContainerCreate(ctx,
+				&container.Config{
+					Image: "busybox",
+					Cmd:   strslice.StrSlice([]string{"top"}),
+				},
+				&container.HostConfig{},
+				&network.NetworkingConfig{},
+				"")
+			require.NoError(t, err)
+			err = client.ContainerStart(ctx, c.ID, types.ContainerStartOptions{})
+			require.NoError(t, err)
+			err = client.ContainerKill(ctx, c.ID, tc.signal)
+			require.NoError(t, err)
+
+			poll.WaitOn(t, containerIsInState(ctx, client, c.ID, tc.status), poll.WithDelay(100*time.Millisecond))
+		})
+	}
+}
+
+func TestKillWithStopSignalAndRestartPolicies(t *testing.T) {
+	skip.If(t, testEnv.OSType != "linux", "Windows only supports 1.25 or later")
+	defer setupTest(t)()
+	client := request.NewAPIClient(t)
+
+	testCases := []struct {
+		doc        string
+		stopsignal string
+		status     string
+	}{
+		{
+			doc:        "same-signal-disables-restart-policy",
+			stopsignal: "TERM",
+			status:     "exited",
+		},
+		{
+			doc:        "different-signal-keep-restart-policy",
+			stopsignal: "CONT",
+			status:     "running",
+		},
+	}
+
+	for _, tc := range testCases {
+		tc := tc
+		t.Run(tc.doc, func(t *testing.T) {
+			ctx := context.Background()
+			c, err := client.ContainerCreate(ctx,
+				&container.Config{
+					Image:      "busybox",
+					Cmd:        strslice.StrSlice([]string{"top"}),
+					StopSignal: tc.stopsignal,
+				},
+				&container.HostConfig{
+					RestartPolicy: container.RestartPolicy{
+						Name: "always",
+					}},
+				&network.NetworkingConfig{},
+				"")
+			require.NoError(t, err)
+			err = client.ContainerStart(ctx, c.ID, types.ContainerStartOptions{})
+			require.NoError(t, err)
+			err = client.ContainerKill(ctx, c.ID, "TERM")
+			require.NoError(t, err)
+
+			poll.WaitOn(t, containerIsInState(ctx, client, c.ID, tc.status), poll.WithDelay(100*time.Millisecond))
+		})
+	}
+}
+
+func TestKillStoppedContainer(t *testing.T) {
+	skip.If(t, testEnv.OSType != "linux") // Windows only supports 1.25 or later
+	defer setupTest(t)()
+	ctx := context.Background()
+	client := request.NewAPIClient(t)
+	c, err := client.ContainerCreate(ctx,
+		&container.Config{
+			Image: "busybox",
+			Cmd:   strslice.StrSlice([]string{"top"}),
+		},
+		&container.HostConfig{},
+		&network.NetworkingConfig{},
+		"")
+	require.NoError(t, err)
+	err = client.ContainerKill(ctx, c.ID, "SIGKILL")
+	require.Error(t, err)
+	require.Contains(t, err.Error(), "is not running")
+}
+
+func TestKillStoppedContainerAPIPre120(t *testing.T) {
+	skip.If(t, testEnv.OSType != "linux") // Windows only supports 1.25 or later
+	defer setupTest(t)()
+	ctx := context.Background()
+	client := request.NewAPIClient(t, client.WithVersion("1.19"))
+	c, err := client.ContainerCreate(ctx,
+		&container.Config{
+			Image: "busybox",
+			Cmd:   strslice.StrSlice([]string{"top"}),
+		},
+		&container.HostConfig{},
+		&network.NetworkingConfig{},
+		"")
+	require.NoError(t, err)
+	err = client.ContainerKill(ctx, c.ID, "SIGKILL")
+	require.NoError(t, err)
+}
diff --git a/components/engine/integration/network/inspect_test.go b/components/engine/integration/network/inspect_test.go
index 36b65d1d11..94218af084 100644
--- a/components/engine/integration/network/inspect_test.go
+++ b/components/engine/integration/network/inspect_test.go
@@ -11,7 +11,6 @@ import (
 	"github.com/docker/docker/api/types/swarm"
 	"github.com/docker/docker/client"
 	"github.com/docker/docker/integration-cli/daemon"
-	"github.com/docker/docker/integration-cli/request"
 	"github.com/gotestyourself/gotestyourself/poll"
 	"github.com/stretchr/testify/require"
 	"golang.org/x/net/context"
@@ -24,7 +23,7 @@ func TestInspectNetwork(t *testing.T) {
 	defer setupTest(t)()
 	d := newSwarm(t)
 	defer d.Stop(t)
-	client, err := request.NewClientForHost(d.Sock())
+	client, err := client.NewClientWithOpts(client.WithHost((d.Sock())))
 	require.NoError(t, err)
 
 	overlayName := "overlay1"
diff --git a/components/engine/integration/secret/secret_test.go b/components/engine/integration/secret/secret_test.go
index 7637304ad8..922fd33028 100644
--- a/components/engine/integration/secret/secret_test.go
+++ b/components/engine/integration/secret/secret_test.go
@@ -4,7 +4,7 @@ import (
 	"testing"
 
 	swarmtypes "github.com/docker/docker/api/types/swarm"
-	"github.com/docker/docker/integration-cli/request"
+	"github.com/docker/docker/client"
 	"github.com/docker/docker/integration/util/swarm"
 	"github.com/gotestyourself/gotestyourself/skip"
 	"github.com/stretchr/testify/assert"
@@ -18,7 +18,7 @@ func TestSecretInspect(t *testing.T) {
 	defer setupTest(t)()
 	d := swarm.NewSwarm(t, testEnv)
 	defer d.Stop(t)
-	client, err := request.NewClientForHost(d.Sock())
+	client, err := client.NewClientWithOpts(client.WithHost((d.Sock())))
 	require.NoError(t, err)
 
 	ctx := context.Background()
diff --git a/components/engine/integration/service/create_test.go b/components/engine/integration/service/create_test.go
index 19b9eee949..c74c8fb52e 100644
--- a/components/engine/integration/service/create_test.go
+++ b/components/engine/integration/service/create_test.go
@@ -10,7 +10,6 @@ import (
 	"github.com/docker/docker/api/types/filters"
 	swarmtypes "github.com/docker/docker/api/types/swarm"
 	"github.com/docker/docker/client"
-	"github.com/docker/docker/integration-cli/request"
 	"github.com/docker/docker/integration/util/swarm"
 	"github.com/gotestyourself/gotestyourself/poll"
 	"github.com/stretchr/testify/assert"
@@ -22,7 +21,7 @@ func TestCreateServiceMultipleTimes(t *testing.T) {
 	defer setupTest(t)()
 	d := swarm.NewSwarm(t, testEnv)
 	defer d.Stop(t)
-	client, err := request.NewClientForHost(d.Sock())
+	client, err := client.NewClientWithOpts(client.WithHost((d.Sock())))
 	require.NoError(t, err)
 
 	overlayName := "overlay1"
@@ -88,7 +87,7 @@ func TestCreateWithDuplicateNetworkNames(t *testing.T) {
 	defer setupTest(t)()
 	d := swarm.NewSwarm(t, testEnv)
 	defer d.Stop(t)
-	client, err := request.NewClientForHost(d.Sock())
+	client, err := client.NewClientWithOpts(client.WithHost((d.Sock())))
 	require.NoError(t, err)
 
 	name := "foo"
@@ -150,7 +149,7 @@ func TestCreateServiceSecretFileMode(t *testing.T) {
 	defer setupTest(t)()
 	d := swarm.NewSwarm(t, testEnv)
 	defer d.Stop(t)
-	client, err := request.NewClientForHost(d.Sock())
+	client, err := client.NewClientWithOpts(client.WithHost((d.Sock())))
 	require.NoError(t, err)
 
 	ctx := context.Background()
@@ -231,7 +230,7 @@ func TestCreateServiceConfigFileMode(t *testing.T) {
 	defer setupTest(t)()
 	d := swarm.NewSwarm(t, testEnv)
 	defer d.Stop(t)
-	client, err := request.NewClientForHost(d.Sock())
+	client, err := client.NewClientWithOpts(client.WithHost((d.Sock())))
 	require.NoError(t, err)
 
 	ctx := context.Background()
diff --git a/components/engine/integration/service/inspect_test.go b/components/engine/integration/service/inspect_test.go
index 2ca0ec6b06..8fe97d98ad 100644
--- a/components/engine/integration/service/inspect_test.go
+++ b/components/engine/integration/service/inspect_test.go
@@ -9,7 +9,6 @@ import (
 	"github.com/docker/docker/api/types/filters"
 	swarmtypes "github.com/docker/docker/api/types/swarm"
 	"github.com/docker/docker/client"
-	"github.com/docker/docker/integration-cli/request"
 	"github.com/docker/docker/integration/util/swarm"
 	"github.com/gotestyourself/gotestyourself/poll"
 	"github.com/gotestyourself/gotestyourself/skip"
@@ -23,7 +22,7 @@ func TestInspect(t *testing.T) {
 	defer setupTest(t)()
 	d := swarm.NewSwarm(t, testEnv)
 	defer d.Stop(t)
-	client, err := request.NewClientForHost(d.Sock())
+	client, err := client.NewClientWithOpts(client.WithHost((d.Sock())))
 	require.NoError(t, err)
 
 	var before = time.Now()
diff --git a/components/engine/integration/service/network_test.go b/components/engine/integration/service/network_test.go
index 089c7ae19c..1a9297c6b3 100644
--- a/components/engine/integration/service/network_test.go
+++ b/components/engine/integration/service/network_test.go
@@ -7,7 +7,7 @@ import (
 	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/api/types/container"
 	"github.com/docker/docker/api/types/network"
-	"github.com/docker/docker/integration-cli/request"
+	"github.com/docker/docker/client"
 	"github.com/docker/docker/integration/util/swarm"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -17,7 +17,7 @@ func TestDockerNetworkConnectAlias(t *testing.T) {
 	defer setupTest(t)()
 	d := swarm.NewSwarm(t, testEnv)
 	defer d.Stop(t)
-	client, err := request.NewClientForHost(d.Sock())
+	client, err := client.NewClientWithOpts(client.WithHost((d.Sock())))
 	require.NoError(t, err)
 	ctx := context.Background()
 
diff --git a/components/engine/integration/util/request/client.go b/components/engine/integration/util/request/client.go
index b4a15a8c99..5c1ec08607 100644
--- a/components/engine/integration/util/request/client.go
+++ b/components/engine/integration/util/request/client.go
@@ -6,7 +6,6 @@ import (
 	"testing"
 	"time"
 
-	"github.com/docker/docker/api"
 	"github.com/docker/docker/client"
 	"github.com/docker/go-connections/sockets"
 	"github.com/docker/go-connections/tlsconfig"
@@ -14,8 +13,9 @@ import (
 )
 
 // NewAPIClient returns a docker API client configured from environment variables
-func NewAPIClient(t *testing.T) client.APIClient {
-	clt, err := client.NewEnvClient()
+func NewAPIClient(t *testing.T, ops ...func(*client.Client) error) client.APIClient {
+	ops = append([]func(*client.Client) error{client.FromEnv}, ops...)
+	clt, err := client.NewClientWithOpts(ops...)
 	require.NoError(t, err)
 	return clt
 }
@@ -47,7 +47,5 @@ func NewTLSAPIClient(t *testing.T, host, cacertPath, certPath, keyPath string) (
 		Transport:     tr,
 		CheckRedirect: client.CheckRedirect,
 	}
-	verStr := api.DefaultVersion
-	customHeaders := map[string]string{}
-	return client.NewClient(host, verStr, httpClient, customHeaders)
+	return client.NewClientWithOpts(client.WithHost(host), client.WithHTTPClient(httpClient))
 }
diff --git a/components/engine/internal/test/environment/environment.go b/components/engine/internal/test/environment/environment.go
index 5ff4139e5d..bde4c0a1bc 100644
--- a/components/engine/internal/test/environment/environment.go
+++ b/components/engine/internal/test/environment/environment.go
@@ -32,7 +32,7 @@ type PlatformDefaults struct {
 
 // New creates a new Execution struct
 func New() (*Execution, error) {
-	client, err := client.NewEnvClient()
+	client, err := client.NewClientWithOpts(client.FromEnv)
 	if err != nil {
 		return nil, errors.Wrapf(err, "failed to create client")
 	}