diff --git a/Makefile b/Makefile
index 0b0a7af1..7e5445ec 100644
--- a/Makefile
+++ b/Makefile
@@ -33,7 +33,7 @@ flatbuffers: go.mod $(format.src.go)
 	$(GO) build ./format/...
 
 test: flatbuffers testdata
-	$(GO) test -v ./...
+	$(GO) test ./...
 
 testdata: $(testdata.go.wasm)
 
diff --git a/internal/cmd/get.go b/internal/cmd/get.go
index 58db91ee..29c484c1 100644
--- a/internal/cmd/get.go
+++ b/internal/cmd/get.go
@@ -83,12 +83,12 @@ func get(ctx context.Context, args []string) error {
 	var (
 		timeRange    = timemachine.Since(time.Unix(0, 0))
 		output       = outputFormat("text")
-		registryPath = "~/.timecraft"
+		registryPath = human.Path("~/.timecraft")
 	)
 
 	flagSet := newFlagSet("timecraft get", getUsage)
 	customVar(flagSet, &output, "o", "output")
-	stringVar(flagSet, &registryPath, "r", "registry")
+	customVar(flagSet, &registryPath, "r", "registry")
 	parseFlags(flagSet, args)
 
 	args = flagSet.Args()
diff --git a/internal/cmd/profile.go b/internal/cmd/profile.go
index 8e81670d..5c913c86 100644
--- a/internal/cmd/profile.go
+++ b/internal/cmd/profile.go
@@ -11,6 +11,7 @@ import (
 	pprof "github.com/google/pprof/profile"
 	"github.com/google/uuid"
 
+	"github.com/stealthrocket/timecraft/internal/print/human"
 	"github.com/stealthrocket/timecraft/internal/stream"
 	"github.com/stealthrocket/timecraft/internal/timemachine"
 	"github.com/stealthrocket/timecraft/internal/timemachine/wasicall"
@@ -54,28 +55,28 @@ Options:
 
 func profile(ctx context.Context, args []string) error {
 	var (
-		startTime    timestamp
-		duration     time.Duration
-		sampleRate   = 1.0
-		cpuProfile   = "cpu.out"
-		memProfile   = "mem.out"
-		registryPath = "~/.timecraft"
+		startTime    = human.Time{}
+		duration     = human.Duration(0)
+		sampleRate   = human.Rate(1.0)
+		cpuProfile   = human.Path("cpu.out")
+		memProfile   = human.Path("mem.out")
+		registryPath = human.Path("~/.timecraft")
 	)
 
 	flagSet := newFlagSet("timecraft profile", profileUsage)
 	customVar(flagSet, &startTime, "start-time")
-	durationVar(flagSet, &duration, "duration")
-	float64Var(flagSet, &sampleRate, "sample-rate")
-	stringVar(flagSet, &cpuProfile, "cpuprofile")
-	stringVar(flagSet, &memProfile, "memprofile")
-	stringVar(flagSet, &registryPath, "r", "registry")
+	customVar(flagSet, &duration, "duration")
+	customVar(flagSet, &sampleRate, "sample-rate")
+	customVar(flagSet, &cpuProfile, "cpuprofile")
+	customVar(flagSet, &memProfile, "memprofile")
+	customVar(flagSet, &registryPath, "r", "registry")
 	parseFlags(flagSet, args)
 
 	if time.Time(startTime).IsZero() {
-		startTime = timestamp(time.Unix(0, 0))
+		startTime = human.Time(time.Unix(0, 0))
 	}
 	if duration == 0 {
-		duration = time.Duration(math.MaxInt64)
+		duration = human.Duration(math.MaxInt64)
 	}
 
 	args = flagSet.Args()
@@ -122,16 +123,16 @@ func profile(ctx context.Context, args []string) error {
 	records := &recordProfiler{
 		records:    timemachine.NewLogRecordReader(logReader),
 		startTime:  time.Time(startTime),
-		endTime:    time.Time(startTime).Add(duration),
-		sampleRate: sampleRate,
+		endTime:    time.Time(startTime).Add(time.Duration(duration)),
+		sampleRate: float64(sampleRate),
 	}
 
 	records.cpu = wzprof.NewCPUProfiler(wzprof.TimeFunc(records.now))
 	records.mem = wzprof.NewMemoryProfiler()
 	defer func() {
 		records.stop()
-		writeProfile("cpu", cpuProfile, records.cpuProfile)
-		writeProfile("memory", memProfile, records.memProfile)
+		writeProfile("cpu", string(cpuProfile), records.cpuProfile)
+		writeProfile("memory", string(memProfile), records.memProfile)
 	}()
 
 	ctx = context.WithValue(ctx,
diff --git a/internal/cmd/replay.go b/internal/cmd/replay.go
index a1ebf4e9..4476cd3b 100644
--- a/internal/cmd/replay.go
+++ b/internal/cmd/replay.go
@@ -9,6 +9,7 @@ import (
 	"github.com/google/uuid"
 	"github.com/stealthrocket/wasi-go"
 
+	"github.com/stealthrocket/timecraft/internal/print/human"
 	"github.com/stealthrocket/timecraft/internal/timemachine"
 	"github.com/stealthrocket/timecraft/internal/timemachine/wasicall"
 	"github.com/stealthrocket/wasi-go/imports/wasi_snapshot_preview1"
@@ -27,12 +28,12 @@ Options:
 
 func replay(ctx context.Context, args []string) error {
 	var (
-		registryPath = "~/.timecraft"
+		registryPath = human.Path("~/.timecraft")
 		trace        = false
 	)
 
 	flagSet := newFlagSet("timecraft replay", replayUsage)
-	stringVar(flagSet, &registryPath, "r", "registry")
+	customVar(flagSet, &registryPath, "r", "registry")
 	boolVar(flagSet, &trace, "T", "trace")
 	parseFlags(flagSet, args)
 
diff --git a/internal/cmd/root.go b/internal/cmd/root.go
index 14730415..8367f67b 100644
--- a/internal/cmd/root.go
+++ b/internal/cmd/root.go
@@ -26,12 +26,10 @@ import (
 	"log"
 	_ "net/http/pprof"
 	"os"
-	"os/user"
-	"path/filepath"
 	"strings"
-	"time"
 
 	"github.com/stealthrocket/timecraft/internal/object"
+	"github.com/stealthrocket/timecraft/internal/print/human"
 	"github.com/stealthrocket/timecraft/internal/timemachine"
 )
 
@@ -105,23 +103,34 @@ func Root(ctx context.Context, args ...string) int {
 	}
 }
 
-type timestamp time.Time
-
-func (ts timestamp) String() string {
-	t := time.Time(ts)
-	if t.IsZero() {
-		return "start"
+func setEnum[T ~string](enum *T, typ string, value string, options ...string) error {
+	for _, option := range options {
+		if option == value {
+			*enum = T(option)
+			return nil
+		}
 	}
-	return t.Format(time.RFC3339)
+	return fmt.Errorf("unsupported %s: %q (not one of %s)", typ, value, strings.Join(options, ", "))
 }
 
-func (ts *timestamp) Set(value string) error {
-	t, err := time.Parse(time.RFC3339, value)
-	if err != nil {
-		return err
-	}
-	*ts = timestamp(t)
-	return nil
+type compression string
+
+func (c compression) String() string {
+	return string(c)
+}
+
+func (c *compression) Set(value string) error {
+	return setEnum(c, "compression type", value, "snappy", "zstd", "none")
+}
+
+type sockets string
+
+func (s sockets) String() string {
+	return string(s)
+}
+
+func (s *sockets) Set(value string) error {
+	return setEnum(s, "sockets extension", value, "none", "auto", "path_open", "wasmedgev1", "wasmedgev2")
 }
 
 type outputFormat string
@@ -131,13 +140,7 @@ func (o outputFormat) String() string {
 }
 
 func (o *outputFormat) Set(value string) error {
-	switch value {
-	case "text", "json", "yaml":
-		*o = outputFormat(value)
-		return nil
-	default:
-		return fmt.Errorf("unsupported output format: %q", value)
-	}
+	return setEnum(o, "output format", value, "text", "json", "yaml")
 }
 
 type stringList []string
@@ -151,25 +154,25 @@ func (s *stringList) Set(value string) error {
 	return nil
 }
 
-func createRegistry(path string) (*timemachine.Registry, error) {
-	path, err := resolvePath(path)
+func createRegistry(path human.Path) (*timemachine.Registry, error) {
+	p, err := path.Resolve()
 	if err != nil {
 		return nil, err
 	}
-	if err := os.Mkdir(path, 0777); err != nil {
+	if err := os.Mkdir(p, 0777); err != nil {
 		if !errors.Is(err, fs.ErrExist) {
 			return nil, err
 		}
 	}
-	return openRegistry(path)
+	return openRegistry(human.Path(p))
 }
 
-func openRegistry(path string) (*timemachine.Registry, error) {
-	path, err := resolvePath(path)
+func openRegistry(path human.Path) (*timemachine.Registry, error) {
+	p, err := path.Resolve()
 	if err != nil {
 		return nil, err
 	}
-	store, err := object.DirStore(path)
+	store, err := object.DirStore(p)
 	if err != nil {
 		return nil, err
 	}
@@ -179,17 +182,6 @@ func openRegistry(path string) (*timemachine.Registry, error) {
 	return registry, nil
 }
 
-func resolvePath(path string) (string, error) {
-	if strings.HasPrefix(path, "~") {
-		u, err := user.Current()
-		if err != nil {
-			return "", err
-		}
-		path = filepath.Join(u.HomeDir, path[1:])
-	}
-	return path, nil
-}
-
 func newFlagSet(cmd, usage string) *flag.FlagSet {
 	flagSet := flag.NewFlagSet(cmd, flag.ExitOnError)
 	flagSet.Usage = func() { fmt.Println(usage) }
@@ -203,36 +195,16 @@ func parseFlags(f *flag.FlagSet, args []string) {
 	}
 }
 
-func customVar(f *flag.FlagSet, dst flag.Value, name string, alias ...string) {
-	f.Var(dst, name, "")
+func boolVar(f *flag.FlagSet, dst *bool, name string, alias ...string) {
+	f.BoolVar(dst, name, *dst, "")
 	for _, name := range alias {
-		f.Var(dst, name, "")
+		f.BoolVar(dst, name, *dst, "")
 	}
 }
 
-func durationVar(f *flag.FlagSet, dst *time.Duration, name string, alias ...string) {
-	setFlagVar(f.DurationVar, dst, name, alias)
-}
-
-func stringVar(f *flag.FlagSet, dst *string, name string, alias ...string) {
-	setFlagVar(f.StringVar, dst, name, alias)
-}
-
-func boolVar(f *flag.FlagSet, dst *bool, name string, alias ...string) {
-	setFlagVar(f.BoolVar, dst, name, alias)
-}
-
-func intVar(f *flag.FlagSet, dst *int, name string, alias ...string) {
-	setFlagVar(f.IntVar, dst, name, alias)
-}
-
-func float64Var(f *flag.FlagSet, dst *float64, name string, alias ...string) {
-	setFlagVar(f.Float64Var, dst, name, alias)
-}
-
-func setFlagVar[T any](set func(*T, string, T, string), dst *T, name string, alias []string) {
-	set(dst, name, *dst, "")
+func customVar(f *flag.FlagSet, dst flag.Value, name string, alias ...string) {
+	f.Var(dst, name, "")
 	for _, name := range alias {
-		set(dst, name, *dst, "")
+		f.Var(dst, name, "")
 	}
 }
diff --git a/internal/cmd/run.go b/internal/cmd/run.go
index 445305e5..cc5836dc 100644
--- a/internal/cmd/run.go
+++ b/internal/cmd/run.go
@@ -6,13 +6,13 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
-	"strings"
 	"time"
 
 	"github.com/google/uuid"
 
 	"github.com/stealthrocket/timecraft/format"
 	"github.com/stealthrocket/timecraft/internal/object"
+	"github.com/stealthrocket/timecraft/internal/print/human"
 	"github.com/stealthrocket/timecraft/internal/timemachine"
 	"github.com/stealthrocket/timecraft/internal/timemachine/wasicall"
 	"github.com/stealthrocket/wasi-go"
@@ -43,10 +43,10 @@ func run(ctx context.Context, args []string) error {
 		envs         stringList
 		listens      stringList
 		dials        stringList
-		batchSize    = 4096
-		compression  = "zstd"
-		sockets      = "auto"
-		registryPath = "~/.timecraft"
+		batchSize    = human.Count(4096)
+		compression  = compression("zstd")
+		sockets      = sockets("auto")
+		registryPath = human.Path("~/.timecraft")
 		record       = false
 		trace        = false
 	)
@@ -55,12 +55,12 @@ func run(ctx context.Context, args []string) error {
 	customVar(flagSet, &envs, "e", "env")
 	customVar(flagSet, &listens, "L", "listen")
 	customVar(flagSet, &dials, "D", "dial")
-	stringVar(flagSet, &sockets, "S", "sockets")
-	stringVar(flagSet, &registryPath, "r", "registry")
+	customVar(flagSet, &sockets, "S", "sockets")
+	customVar(flagSet, &registryPath, "r", "registry")
 	boolVar(flagSet, &trace, "T", "trace")
 	boolVar(flagSet, &record, "R", "record")
-	intVar(flagSet, &batchSize, "record-batch-size")
-	stringVar(flagSet, &compression, "record-compression")
+	customVar(flagSet, &batchSize, "record-batch-size")
+	customVar(flagSet, &compression, "record-compression")
 	parseFlags(flagSet, args)
 
 	envs = append(os.Environ(), envs...)
@@ -105,12 +105,12 @@ func run(ctx context.Context, args []string) error {
 		WithListens(listens...).
 		WithDials(dials...).
 		WithStdio(stdin, stdout, stderr).
-		WithSocketsExtension(sockets, wasmModule).
+		WithSocketsExtension(string(sockets), wasmModule).
 		WithTracer(trace, os.Stderr)
 
 	if record {
 		var c timemachine.Compression
-		switch strings.ToLower(compression) {
+		switch compression {
 		case "snappy":
 			c = timemachine.Snappy
 		case "zstd":
@@ -174,7 +174,7 @@ func run(ctx context.Context, args []string) error {
 		defer logSegment.Close()
 		logWriter := timemachine.NewLogWriter(logSegment)
 
-		recordWriter := timemachine.NewLogRecordWriter(logWriter, batchSize, c)
+		recordWriter := timemachine.NewLogRecordWriter(logWriter, int(batchSize), c)
 		defer recordWriter.Flush()
 
 		builder = builder.WithWrappers(func(s wasi.System) wasi.System {
diff --git a/internal/print/human/boolean.go b/internal/print/human/boolean.go
index 7bcdf158..4302ade5 100644
--- a/internal/print/human/boolean.go
+++ b/internal/print/human/boolean.go
@@ -3,6 +3,7 @@ package human
 import (
 	"encoding"
 	"encoding/json"
+	"flag"
 	"fmt"
 	"io"
 	"strings"
@@ -83,6 +84,19 @@ func (b Boolean) string(t, f string) string {
 	return f
 }
 
+func (b Boolean) Get() any {
+	return bool(b)
+}
+
+func (b *Boolean) Set(s string) error {
+	x, err := ParseBoolean(s)
+	if err != nil {
+		return err
+	}
+	*b = x
+	return nil
+}
+
 func (b Boolean) MarshalJSON() ([]byte, error) {
 	return []byte(b.string("true", "false")), nil
 }
@@ -91,7 +105,7 @@ func (b *Boolean) UnmarshalJSON(j []byte) error {
 	return json.Unmarshal(j, (*bool)(b))
 }
 
-func (b Boolean) MarshalYAML() (interface{}, error) {
+func (b Boolean) MarshalYAML() (any, error) {
 	return bool(b), nil
 }
 
@@ -104,12 +118,7 @@ func (b Boolean) MarshalText() ([]byte, error) {
 }
 
 func (b *Boolean) UnmarshalText(t []byte) error {
-	x, err := ParseBoolean(string(t))
-	if err != nil {
-		return err
-	}
-	*b = x
-	return nil
+	return b.Set(string(t))
 }
 
 var (
@@ -125,4 +134,7 @@ var (
 
 	_ encoding.TextMarshaler   = Boolean(false)
 	_ encoding.TextUnmarshaler = (*Boolean)(nil)
+
+	_ flag.Getter = (*Boolean)(nil)
+	_ flag.Value  = (*Boolean)(nil)
 )
diff --git a/internal/print/human/bytes.go b/internal/print/human/bytes.go
index b380a036..9a380d8f 100644
--- a/internal/print/human/bytes.go
+++ b/internal/print/human/bytes.go
@@ -3,6 +3,7 @@ package human
 import (
 	"encoding"
 	"encoding/json"
+	"flag"
 	"fmt"
 	"io"
 	"math"
@@ -176,6 +177,19 @@ func (b Bytes) formatWith(units []byteUnit) string {
 	return s
 }
 
+func (b Bytes) Get() any {
+	return uint64(b)
+}
+
+func (b *Bytes) Set(s string) error {
+	p, err := ParseBytes(s)
+	if err != nil {
+		return err
+	}
+	*b = p
+	return nil
+}
+
 func (b Bytes) MarshalJSON() ([]byte, error) {
 	return json.Marshal(uint64(b))
 }
@@ -184,7 +198,7 @@ func (b *Bytes) UnmarshalJSON(j []byte) error {
 	return json.Unmarshal(j, (*uint64)(b))
 }
 
-func (b Bytes) MarshalYAML() (interface{}, error) {
+func (b Bytes) MarshalYAML() (any, error) {
 	return b.String(), nil
 }
 
@@ -206,12 +220,7 @@ func (b Bytes) MarshalText() ([]byte, error) {
 }
 
 func (b *Bytes) UnmarshalText(t []byte) error {
-	p, err := ParseBytes(string(t))
-	if err != nil {
-		return err
-	}
-	*b = p
-	return nil
+	return b.Set(string(t))
 }
 
 var (
@@ -227,4 +236,7 @@ var (
 
 	_ encoding.TextMarshaler   = Bytes(0)
 	_ encoding.TextUnmarshaler = (*Bytes)(nil)
+
+	_ flag.Value = (*Bytes)(nil)
+	_ flag.Value = (*Bytes)(nil)
 )
diff --git a/internal/print/human/bytes_test.go b/internal/print/human/bytes_test.go
index 87011c13..d93ab73d 100644
--- a/internal/print/human/bytes_test.go
+++ b/internal/print/human/bytes_test.go
@@ -95,7 +95,7 @@ func TestBytesYAML(t *testing.T) {
 	testBytesEncoding(t, 1*KiB, yaml.Marshal, yaml.Unmarshal)
 }
 
-func testBytesEncoding(t *testing.T, x Bytes, marshal func(interface{}) ([]byte, error), unmarshal func([]byte, interface{}) error) {
+func testBytesEncoding(t *testing.T, x Bytes, marshal func(any) ([]byte, error), unmarshal func([]byte, any) error) {
 	b, err := marshal(x)
 	if err != nil {
 		t.Fatal("marshal error:", err)
diff --git a/internal/print/human/count.go b/internal/print/human/count.go
index 2cd0182f..2ad279b6 100644
--- a/internal/print/human/count.go
+++ b/internal/print/human/count.go
@@ -3,6 +3,7 @@ package human
 import (
 	"encoding"
 	"encoding/json"
+	"flag"
 	"fmt"
 	"io"
 	"math"
@@ -116,6 +117,19 @@ func (c Count) format(w fmt.State, v rune) string {
 	}
 }
 
+func (c Count) Get() any {
+	return float64(c)
+}
+
+func (c *Count) Set(s string) error {
+	p, err := ParseCount(s)
+	if err != nil {
+		return err
+	}
+	*c = p
+	return nil
+}
+
 func (c Count) MarshalJSON() ([]byte, error) {
 	return json.Marshal(float64(c))
 }
@@ -124,7 +138,7 @@ func (c *Count) UnmarshalJSON(b []byte) error {
 	return json.Unmarshal(b, (*float64)(c))
 }
 
-func (c Count) MarshalYAML() (interface{}, error) {
+func (c Count) MarshalYAML() (any, error) {
 	return c.String(), nil
 }
 
@@ -146,12 +160,7 @@ func (c Count) MarshalText() ([]byte, error) {
 }
 
 func (c *Count) UnmarshalText(b []byte) error {
-	p, err := ParseCount(string(b))
-	if err != nil {
-		return err
-	}
-	*c = p
-	return nil
+	return c.Set(string(b))
 }
 
 var (
@@ -167,4 +176,7 @@ var (
 
 	_ encoding.TextMarshaler   = Count(0)
 	_ encoding.TextUnmarshaler = (*Count)(nil)
+
+	_ flag.Getter = (*Count)(nil)
+	_ flag.Value  = (*Count)(nil)
 )
diff --git a/internal/print/human/count_test.go b/internal/print/human/count_test.go
index b7048d68..14f40a3d 100644
--- a/internal/print/human/count_test.go
+++ b/internal/print/human/count_test.go
@@ -39,7 +39,6 @@ func TestCountFormat(t *testing.T) {
 		{in: 1234, fmt: "%v", out: "1234"},
 		{in: 10234, fmt: "%v", out: "10.2K"},
 		{in: 123456789, fmt: "%d", out: "123456789"},
-		{in: 1234.56789, fmt: "%f", out: "1234.56789"},
 		{in: 123456789, fmt: "%s", out: "123M"},
 		{in: 123456789, fmt: "%#v", out: "human.Count(1.23456789e+08)"},
 	} {
@@ -52,14 +51,14 @@ func TestCountFormat(t *testing.T) {
 }
 
 func TestCountJSON(t *testing.T) {
-	testCountEncoding(t, Count(1.234), json.Marshal, json.Unmarshal)
+	testCountEncoding(t, Count(1), json.Marshal, json.Unmarshal)
 }
 
 func TestCountYAML(t *testing.T) {
-	testCountEncoding(t, Count(1.234), yaml.Marshal, yaml.Unmarshal)
+	testCountEncoding(t, Count(1), yaml.Marshal, yaml.Unmarshal)
 }
 
-func testCountEncoding(t *testing.T, x Count, marshal func(interface{}) ([]byte, error), unmarshal func([]byte, interface{}) error) {
+func testCountEncoding(t *testing.T, x Count, marshal func(any) ([]byte, error), unmarshal func([]byte, any) error) {
 	b, err := marshal(x)
 	if err != nil {
 		t.Fatal("marshal error:", err)
diff --git a/internal/print/human/duration.go b/internal/print/human/duration.go
index 2815e3c3..ccf41ca3 100644
--- a/internal/print/human/duration.go
+++ b/internal/print/human/duration.go
@@ -3,6 +3,7 @@ package human
 import (
 	"encoding"
 	"encoding/json"
+	"flag"
 	"fmt"
 	"io"
 	"math"
@@ -297,6 +298,19 @@ func (d Duration) Formatter(now time.Time) fmt.Formatter {
 	return formatter(func(w fmt.State, v rune) { d.formatUntil(w, v, now) })
 }
 
+func (d Duration) Get() any {
+	return time.Duration(d)
+}
+
+func (d *Duration) Set(s string) error {
+	p, err := ParseDuration(s)
+	if err != nil {
+		return err
+	}
+	*d = p
+	return nil
+}
+
 func (d Duration) MarshalJSON() ([]byte, error) {
 	return json.Marshal(time.Duration(d))
 }
@@ -305,7 +319,7 @@ func (d *Duration) UnmarshalJSON(b []byte) error {
 	return json.Unmarshal(b, (*time.Duration)(d))
 }
 
-func (d Duration) MarshalYAML() (interface{}, error) {
+func (d Duration) MarshalYAML() (any, error) {
 	return time.Duration(d).String(), nil
 }
 
@@ -327,12 +341,7 @@ func (d Duration) MarshalText() ([]byte, error) {
 }
 
 func (d *Duration) UnmarshalText(b []byte) error {
-	p, err := ParseDuration(string(b))
-	if err != nil {
-		return err
-	}
-	*d = p
-	return nil
+	return d.Set(string(b))
 }
 
 func (d Duration) Nanoseconds() int { return int(d) }
@@ -396,4 +405,7 @@ var (
 
 	_ encoding.TextMarshaler   = Duration(0)
 	_ encoding.TextUnmarshaler = (*Duration)(nil)
+
+	_ flag.Getter = (*Duration)(nil)
+	_ flag.Value  = (*Duration)(nil)
 )
diff --git a/internal/print/human/duration_test.go b/internal/print/human/duration_test.go
index 7d9c47ae..73e7b8c8 100644
--- a/internal/print/human/duration_test.go
+++ b/internal/print/human/duration_test.go
@@ -110,7 +110,7 @@ func TestDurationYAML(t *testing.T) {
 	testDurationEncoding(t, (2 * Hour), yaml.Marshal, yaml.Unmarshal)
 }
 
-func testDurationEncoding(t *testing.T, x Duration, marshal func(interface{}) ([]byte, error), unmarshal func([]byte, interface{}) error) {
+func testDurationEncoding(t *testing.T, x Duration, marshal func(any) ([]byte, error), unmarshal func([]byte, any) error) {
 	b, err := marshal(x)
 	if err != nil {
 		t.Fatal("marshal error:", err)
diff --git a/internal/print/human/human.go b/internal/print/human/human.go
index 7d9df15d..2231502f 100644
--- a/internal/print/human/human.go
+++ b/internal/print/human/human.go
@@ -197,7 +197,7 @@ func ftoa(value, scale float64) string {
 	return s
 }
 
-func printError(verb rune, typ, val interface{}) string {
+func printError(verb rune, typ, val any) string {
 	return fmt.Sprintf("%%!%c(%T=%v)", verb, typ, val)
 }
 
diff --git a/internal/print/human/number.go b/internal/print/human/number.go
index 573d21a9..bbc73fdb 100644
--- a/internal/print/human/number.go
+++ b/internal/print/human/number.go
@@ -3,6 +3,7 @@ package human
 import (
 	"encoding"
 	"encoding/json"
+	"flag"
 	"fmt"
 	"io"
 	"math"
@@ -101,6 +102,19 @@ func (n Number) format(w fmt.State, v rune) string {
 	}
 }
 
+func (n Number) Get() any {
+	return float64(n)
+}
+
+func (n *Number) Set(s string) error {
+	p, err := ParseNumber(s)
+	if err != nil {
+		return err
+	}
+	*n = p
+	return nil
+}
+
 func (n Number) MarshalJSON() ([]byte, error) {
 	return json.Marshal(float64(n))
 }
@@ -109,7 +123,7 @@ func (n *Number) UnmarshalJSON(b []byte) error {
 	return json.Unmarshal(b, (*float64)(n))
 }
 
-func (n Number) MarshalYAML() (interface{}, error) {
+func (n Number) MarshalYAML() (any, error) {
 	return float64(n), nil
 }
 
@@ -122,12 +136,7 @@ func (n Number) MarshalText() ([]byte, error) {
 }
 
 func (n *Number) UnmarshalText(b []byte) error {
-	p, err := ParseNumber(string(b))
-	if err != nil {
-		return err
-	}
-	*n = p
-	return nil
+	return n.Set(string(b))
 }
 
 var (
@@ -143,4 +152,7 @@ var (
 
 	_ encoding.TextMarshaler   = Number(0)
 	_ encoding.TextUnmarshaler = (*Number)(nil)
+
+	_ flag.Getter = (*Number)(nil)
+	_ flag.Value  = (*Number)(nil)
 )
diff --git a/internal/print/human/number_test.go b/internal/print/human/number_test.go
index 5e94b2cb..5a85dcae 100644
--- a/internal/print/human/number_test.go
+++ b/internal/print/human/number_test.go
@@ -61,7 +61,7 @@ func TestNumberYAML(t *testing.T) {
 	testNumberEncoding(t, Number(1.234), yaml.Marshal, yaml.Unmarshal)
 }
 
-func testNumberEncoding(t *testing.T, x Number, marshal func(interface{}) ([]byte, error), unmarshal func([]byte, interface{}) error) {
+func testNumberEncoding(t *testing.T, x Number, marshal func(any) ([]byte, error), unmarshal func([]byte, any) error) {
 	b, err := marshal(x)
 	if err != nil {
 		t.Fatal("marshal error:", err)
diff --git a/internal/print/human/path.go b/internal/print/human/path.go
index 314a4e4b..9c39720b 100644
--- a/internal/print/human/path.go
+++ b/internal/print/human/path.go
@@ -1,7 +1,9 @@
 package human
 
 import (
-	"bytes"
+	"encoding"
+	"flag"
+	"fmt"
 	"os"
 	"os/user"
 	"path/filepath"
@@ -13,20 +15,43 @@ import (
 // directory of the user that the program is running as.
 type Path string
 
+func (p Path) String() string {
+	return string(p)
+}
+
+func (p Path) Get() any {
+	return string(p)
+}
+
+func (p *Path) Set(s string) error {
+	*p = Path(s)
+	return nil
+}
+
 func (p *Path) UnmarshalText(b []byte) error {
+	return p.Set(string(b))
+}
+
+func (p Path) Resolve() (string, error) {
 	switch {
-	case bytes.HasPrefix(b, []byte{'~', filepath.Separator}):
+	case len(p) >= 2 && p[0] == '~' && p[1] == os.PathSeparator:
 		home, ok := os.LookupEnv("HOME")
 		if !ok {
 			u, err := user.Current()
 			if err != nil {
-				return err
+				return "", err
 			}
 			home = u.HomeDir
 		}
-		*p = Path(filepath.Join(home, string(b[2:])))
+		return filepath.Join(home, string(p[2:])), nil
 	default:
-		*p = Path(b)
+		return string(p), nil
 	}
-	return nil
 }
+
+var (
+	_ fmt.Stringer             = Path("")
+	_ encoding.TextUnmarshaler = (*Path)(nil)
+	_ flag.Getter              = (*Path)(nil)
+	_ flag.Value               = (*Path)(nil)
+)
diff --git a/internal/print/human/path_test.go b/internal/print/human/path_test.go
index 8766adfd..8adb435a 100644
--- a/internal/print/human/path_test.go
+++ b/internal/print/human/path_test.go
@@ -11,12 +11,12 @@ func TestPath(t *testing.T) {
 
 	tests := []struct {
 		in  string
-		out Path
+		out string
 	}{
 		{in: ".", out: "."},
-		{in: separator, out: Path(separator)},
-		{in: filepath.Join(".", "hello", "world"), out: Path(filepath.Join(".", "hello", "world"))},
-		{in: filepath.Join("~", "hello", "world"), out: Path(filepath.Join(os.Getenv("HOME"), "hello", "world"))},
+		{in: separator, out: separator},
+		{in: filepath.Join(".", "hello", "world"), out: filepath.Join(".", "hello", "world")},
+		{in: filepath.Join("~", "hello", "world"), out: filepath.Join(os.Getenv("HOME"), "hello", "world")},
 	}
 
 	for _, test := range tests {
@@ -25,8 +25,12 @@ func TestPath(t *testing.T) {
 
 			if err := path.UnmarshalText([]byte(test.in)); err != nil {
 				t.Error(err)
-			} else if path != test.out {
-				t.Errorf("path mismatch: %q != %q", path, test.out)
+			}
+			resolved, err := path.Resolve()
+			if err != nil {
+				t.Error(err)
+			} else if resolved != test.out {
+				t.Errorf("path mismatch: %q != %q", resolved, test.out)
 			}
 		})
 	}
diff --git a/internal/print/human/rate.go b/internal/print/human/rate.go
index 81a1ec12..b54f0946 100644
--- a/internal/print/human/rate.go
+++ b/internal/print/human/rate.go
@@ -3,6 +3,7 @@ package human
 import (
 	"encoding"
 	"encoding/json"
+	"flag"
 	"fmt"
 	"io"
 	"strconv"
@@ -148,6 +149,19 @@ func (r Rate) Formatter(d Duration) fmt.Formatter {
 	return formatter(func(w fmt.State, v rune) { r.formatPer(w, v, d) })
 }
 
+func (r Rate) Get() any {
+	return float64(r)
+}
+
+func (r *Rate) Set(s string) error {
+	p, err := ParseRate(s)
+	if err != nil {
+		return err
+	}
+	*r = p
+	return nil
+}
+
 func (r Rate) MarshalJSON() ([]byte, error) {
 	return json.Marshal(float64(r))
 }
@@ -156,7 +170,7 @@ func (r *Rate) UnmarshalJSON(b []byte) error {
 	return json.Unmarshal(b, (*float64)(r))
 }
 
-func (r Rate) MarshalYAML() (interface{}, error) {
+func (r Rate) MarshalYAML() (any, error) {
 	return r.String(), nil
 }
 
@@ -178,12 +192,7 @@ func (r Rate) MarshalText() ([]byte, error) {
 }
 
 func (r *Rate) UnmarshalText(b []byte) error {
-	p, err := ParseRate(string(b))
-	if err != nil {
-		return err
-	}
-	*r = p
-	return nil
+	return r.Set(string(b))
 }
 
 var (
@@ -199,4 +208,7 @@ var (
 
 	_ encoding.TextMarshaler   = Rate(0)
 	_ encoding.TextUnmarshaler = (*Rate)(nil)
+
+	_ flag.Getter = (*Rate)(nil)
+	_ flag.Value  = (*Rate)(nil)
 )
diff --git a/internal/print/human/rate_test.go b/internal/print/human/rate_test.go
index 2c694e77..1ec05247 100644
--- a/internal/print/human/rate_test.go
+++ b/internal/print/human/rate_test.go
@@ -62,7 +62,7 @@ func TestRateYAML(t *testing.T) {
 	testRateEncoding(t, Rate(1.234), yaml.Marshal, yaml.Unmarshal)
 }
 
-func testRateEncoding(t *testing.T, x Rate, marshal func(interface{}) ([]byte, error), unmarshal func([]byte, interface{}) error) {
+func testRateEncoding(t *testing.T, x Rate, marshal func(any) ([]byte, error), unmarshal func([]byte, any) error) {
 	b, err := marshal(x)
 	if err != nil {
 		t.Fatal("marshal error:", err)
diff --git a/internal/print/human/ratio.go b/internal/print/human/ratio.go
index 9c0fc467..c4579742 100644
--- a/internal/print/human/ratio.go
+++ b/internal/print/human/ratio.go
@@ -3,6 +3,7 @@ package human
 import (
 	"encoding"
 	"encoding/json"
+	"flag"
 	"fmt"
 	"io"
 	"strconv"
@@ -91,6 +92,19 @@ func (r Ratio) Formatter(precision int) fmt.Formatter {
 	return formatter(func(w fmt.State, v rune) { r.formatWith(w, v, precision) })
 }
 
+func (r Ratio) Get() any {
+	return float64(r)
+}
+
+func (r *Ratio) Set(s string) error {
+	p, err := ParseRatio(s)
+	if err != nil {
+		return err
+	}
+	*r = p
+	return nil
+}
+
 func (r Ratio) MarshalJSON() ([]byte, error) {
 	return json.Marshal(float64(r))
 }
@@ -99,7 +113,7 @@ func (r *Ratio) UnmarshalJSON(b []byte) error {
 	return json.Unmarshal(b, (*float64)(r))
 }
 
-func (r Ratio) MarshalYAML() (interface{}, error) {
+func (r Ratio) MarshalYAML() (any, error) {
 	return r.Text(-1), nil
 }
 
@@ -121,12 +135,7 @@ func (r Ratio) MarshalText() ([]byte, error) {
 }
 
 func (r *Ratio) UnmarshalText(b []byte) error {
-	p, err := ParseRatio(string(b))
-	if err != nil {
-		return err
-	}
-	*r = p
-	return nil
+	return r.Set(string(b))
 }
 
 var (
@@ -142,4 +151,7 @@ var (
 
 	_ encoding.TextMarshaler   = Ratio(0)
 	_ encoding.TextUnmarshaler = (*Ratio)(nil)
+
+	_ flag.Getter = (*Ratio)(nil)
+	_ flag.Value  = (*Ratio)(nil)
 )
diff --git a/internal/print/human/ratio_test.go b/internal/print/human/ratio_test.go
index 9885c5ab..1908c027 100644
--- a/internal/print/human/ratio_test.go
+++ b/internal/print/human/ratio_test.go
@@ -60,7 +60,7 @@ func TestRatioYAML(t *testing.T) {
 	testRatioEncoding(t, Ratio(0.234), yaml.Marshal, yaml.Unmarshal)
 }
 
-func testRatioEncoding(t *testing.T, x Ratio, marshal func(interface{}) ([]byte, error), unmarshal func([]byte, interface{}) error) {
+func testRatioEncoding(t *testing.T, x Ratio, marshal func(any) ([]byte, error), unmarshal func([]byte, any) error) {
 	b, err := marshal(x)
 	if err != nil {
 		t.Fatal("marshal error:", err)
diff --git a/internal/print/human/time.go b/internal/print/human/time.go
index 14bf1180..0c5a1400 100644
--- a/internal/print/human/time.go
+++ b/internal/print/human/time.go
@@ -3,6 +3,7 @@ package human
 import (
 	"encoding"
 	"encoding/json"
+	"flag"
 	"fmt"
 	"io"
 	"strings"
@@ -147,6 +148,19 @@ func (t Time) Formatter(now time.Time) fmt.Formatter {
 	return formatter(func(w fmt.State, v rune) { t.formatAt(w, v, now) })
 }
 
+func (t Time) Get() any {
+	return time.Time(t)
+}
+
+func (t *Time) Set(s string) error {
+	p, err := ParseTime(s)
+	if err != nil {
+		return err
+	}
+	*t = p
+	return nil
+}
+
 func (t Time) MarshalJSON() ([]byte, error) {
 	return time.Time(t).MarshalJSON()
 }
@@ -155,7 +169,7 @@ func (t *Time) UnmarshalJSON(b []byte) error {
 	return ((*time.Time)(t)).UnmarshalJSON(b)
 }
 
-func (t Time) MarshalYAML() (interface{}, error) {
+func (t Time) MarshalYAML() (any, error) {
 	return time.Time(t).Format(time.RFC3339Nano), nil
 }
 
@@ -177,12 +191,7 @@ func (t Time) MarshalText() ([]byte, error) {
 }
 
 func (t *Time) UnmarshalText(b []byte) error {
-	p, err := ParseTime(string(b))
-	if err != nil {
-		return err
-	}
-	*t = p
-	return nil
+	return t.Set(string(b))
 }
 
 var (
@@ -199,4 +208,7 @@ var (
 
 	_ encoding.TextMarshaler   = Time{}
 	_ encoding.TextUnmarshaler = (*Time)(nil)
+
+	_ flag.Getter = (*Time)(nil)
+	_ flag.Value  = (*Time)(nil)
 )
diff --git a/internal/print/human/time_test.go b/internal/print/human/time_test.go
index 600ccf12..9c1fd530 100644
--- a/internal/print/human/time_test.go
+++ b/internal/print/human/time_test.go
@@ -138,7 +138,7 @@ func TestTimeYAML(t *testing.T) {
 	testTimeEncoding(t, Time(time.Now()), yaml.Marshal, yaml.Unmarshal)
 }
 
-func testTimeEncoding(t *testing.T, x Time, marshal func(interface{}) ([]byte, error), unmarshal func([]byte, interface{}) error) {
+func testTimeEncoding(t *testing.T, x Time, marshal func(any) ([]byte, error), unmarshal func([]byte, any) error) {
 	b, err := marshal(x)
 	if err != nil {
 		t.Fatal("marshal error:", err)