README  |  12 ++++++++++++
 go.mod  |  10 ++++++++++
 go.sum  |  14 ++++++++++++++
 main.go | 134 +++++++++++++++++++++++++++++++++++++++++++++++++++++

diff --git a/README b/README
new file mode 100644
index 0000000000000000000000000000000000000000..f707fffc633149079c47a6656d6e6aa81e8bded5d51f38ec06af397c2893dd6b
--- /dev/null
+++ b/README
@@ -0,0 +1,12 @@
+Print various GeoIP information for specified IP address.
+
+    $ sgeo 2a11:e140:0:11::1
+    Net: 2a11:e140::/32
+    ASN: 212165
+    Org: Alex Group LLC
+    City: Moscow
+    Region: Moscow
+    Country: RU (Russia)
+    Continent: EU (Europe)
+    Lat/Lon: 55.738600/37.744700
+    Distance: 12.34
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000000000000000000000000000000000000..0bcc85c68f3bfef9df30a5f7c8243554372278071773e604a04246e279af07a3
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,10 @@
+module go.stargrave.org/sgeo
+
+go 1.26.2
+
+require github.com/oschwald/geoip2-golang/v2 v2.1.0
+
+require (
+	github.com/oschwald/maxminddb-golang/v2 v2.1.1 // indirect
+	golang.org/x/sys v0.38.0 // indirect
+)
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000000000000000000000000000000000000..43a480a6c2841732d78d6568d7f36a39859b741ed3e483ecfd4899013375dc0d
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,14 @@
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/oschwald/geoip2-golang/v2 v2.1.0 h1:DjnLhNJu9WHwTrmoiQFvgmyJoczhdnm7LB23UBI2Amo=
+github.com/oschwald/geoip2-golang/v2 v2.1.0/go.mod h1:qdVmcPgrTJ4q2eP9tHq/yldMTdp2VMr33uVdFbHBiBc=
+github.com/oschwald/maxminddb-golang/v2 v2.1.1 h1:lA8FH0oOrM4u7mLvowq8IT6a3Q/qEnqRzLQn9eH5ojc=
+github.com/oschwald/maxminddb-golang/v2 v2.1.1/go.mod h1:PLdx6PR+siSIoXqqy7C7r3SB3KZnhxWr1Dp6g0Hacl8=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
+github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
+golang.org/x/sys v0.38.0 h1:3yZWxaJjBmCWXqhN1qh02AkOnCQ1poK6oF+a7xWL6Gc=
+golang.org/x/sys v0.38.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
diff --git a/main.go b/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..e1c9336d3793c6813420cfb6a058d60b9fcdbf340a59462e0c782e8e7ba14239
--- /dev/null
+++ b/main.go
@@ -0,0 +1,134 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"log"
+	"math"
+	"net/netip"
+	"os"
+	"strconv"
+	"strings"
+
+	"github.com/oschwald/geoip2-golang/v2"
+)
+
+const (
+	DegToRad = 0.017453292519943295769236907684886127134428718885417 // N[Pi/180, 50]
+)
+
+var (
+	DefaultLoc   = "55.91666666,37.81666666"
+	MyLat, MyLon float64
+)
+
+func GetDistanceKm(lat1, lon1, lat2, lon2 float64) float64 {
+	// taken from github.com/etix/mirrorbits/utils/utils.go
+	R := float64(6371) // radius of the earth in Km
+	dLat := (lat2 - lat1) * DegToRad
+	dLon := (lon2 - lon1) * DegToRad
+	a := (math.Sin(dLat/2)*
+		math.Sin(dLat/2) +
+		math.Cos(lat1*DegToRad)*
+			math.Cos(lat2*DegToRad)*
+			math.Sin(dLon/2)*
+			math.Sin(dLon/2))
+	c := 2 * math.Atan2(math.Sqrt(a), math.Sqrt(1-a))
+	return R * c
+}
+
+func main() {
+	if s, _ := os.LookupEnv("MYLOC"); s != "" {
+		DefaultLoc = s
+	}
+	myLoc := flag.String("myloc", DefaultLoc, "My location")
+	asnsPth := flag.String("asns", "asns.mmdb", "Path to database with ASNs")
+	citiesPth := flag.String("cities", "cities.mmdb", "Path to database with cities")
+	cgi := flag.Bool("cgi", false, "Be a CGI scrit")
+	flag.Parse()
+	if *cgi {
+		log.SetOutput(os.Stdout)
+		fmt.Print("Content-Type: text/plain\n\n")
+	}
+	var err error
+	{
+		cols := strings.Split(*myLoc, ",")
+		if len(cols) != 2 {
+			log.Fatal("bad -myloc format")
+		}
+		MyLat, err = strconv.ParseFloat(cols[0], 10)
+		if err != nil {
+			log.Fatal(err)
+		}
+		MyLon, err = strconv.ParseFloat(cols[1], 10)
+		if err != nil {
+			log.Fatal(err)
+		}
+	}
+	var addr string
+	if *cgi {
+		addr, _ = os.LookupEnv("PATH_INFO")
+		addr = strings.TrimLeft(addr, "/")
+	} else {
+		if flag.NArg() == 0 {
+			log.Fatal("no IP asked")
+		}
+		addr = flag.Arg(0)
+	}
+
+	ip, err := netip.ParseAddr(addr)
+	if err != nil {
+		log.Fatal(err)
+	}
+	asns, err := geoip2.Open(*asnsPth)
+	if err != nil {
+		log.Fatal(err)
+	}
+	cities, err := geoip2.Open(*citiesPth)
+	if err != nil {
+		log.Fatal(err)
+	}
+	{
+		rec, err := asns.ASN(ip)
+		asns.Close()
+		if err != nil {
+			log.Fatal(err)
+		}
+		if !rec.HasData() {
+			goto NoASN
+		}
+		fmt.Printf("Net: %v\n", rec.Network)
+		fmt.Printf("ASN: %v\n", rec.AutonomousSystemNumber)
+		fmt.Printf("Org: %v\n", rec.AutonomousSystemOrganization)
+	}
+NoASN:
+	{
+		rec, err := cities.City(ip)
+		cities.Close()
+		if err != nil {
+			log.Fatal(err)
+		}
+		if !rec.HasData() {
+			goto NoCity
+		}
+		if len(rec.City.Names.English) > 0 {
+			fmt.Printf("City: %v\n", rec.City.Names.English)
+		}
+		if len(rec.Subdivisions) > 0 {
+			fmt.Printf("Region: %v\n", rec.Subdivisions[0].Names.English)
+		}
+		fmt.Printf("Country: %v (%v)\n",
+			rec.Country.ISOCode,
+			rec.Country.Names.English)
+		fmt.Printf("Continent: %v (%v)\n",
+			rec.Continent.Code,
+			rec.Continent.Names.English)
+		if rec.Location.Latitude != nil && rec.Location.Longitude != nil {
+			fmt.Printf("Lat/Lon: %f/%f\n",
+				*rec.Location.Latitude, *rec.Location.Longitude)
+			fmt.Printf("Distance: %f\n", GetDistanceKm(
+				MyLat, MyLon, *rec.Location.Latitude, *rec.Location.Longitude))
+		}
+	}
+NoCity:
+}