Installation

skyl is four Go modules in one repository. Which ones you install determines what dependencies you inherit, so this page is worth two minutes even though the command is one line.

You will learn

Which module to install, and what each one costs you
Why the Anthropic adapter is a separate go get
The Go version floor for each module, and why they differ
How to verify the install without an API key

The core library#

Terminal

go get github.com/BAGOMBEKA-JOB-DEV/skyl

That gives you the Client, the conversation model, streaming, the error surface, and three of the four adapters — openai, gemini, and openaicompat.

It requires Go 1.22 or later, and it has zero external dependencies. Not "few". None. go.mod has no require block for anything outside the standard library.

Deep diveWhy zero dependencies is a feature and not a boast

Every dependency in a library is imposed on everyone who imports it, forever — including their security scanners, their upgrade schedule, and their vulnerability triage rota. A logging framework you chose in 2024 becomes a CVE someone else has to respond to in 2027.

skyl's engineering rules make this concrete: the core module takes only what it genuinely needs, and it turns out a well-written HTTP client needs nothing. net/http and encoding/json are enough.

The consequence you can see: go get on skyl adds one line to your go.sum tree instead of forty.

The Anthropic adapter#

Claude support is a separate module, and you install it explicitly:

Terminal

go get github.com/BAGOMBEKA-JOB-DEV/skyl/provider/anthropic

It requires Go 1.24 or later.

The reason is the one above, applied honestly. This adapter is built on the official anthropic-sdk-go, which brings roughly a dozen transitive dependencies and sets its own Go floor. Putting it in the core module would charge every skyl user — including people who only ever call Gemini — for a vendor SDK they never touch.

The optional extras#

Two more modules exist. You install them only if you want what they do.

Module	Import path	Go	Dependencies
skyl	`github.com/BAGOMBEKA-JOB-DEV/skyl`	1.22	noneThe core library. Zero external dependencies.
provider/anthropic	`github.com/BAGOMBEKA-JOB-DEV/skyl/provider/anthropic`	1.24	anthropic-sdk-goA separate module, because the official SDK brings a dozen transitive dependencies.
gateway	`github.com/BAGOMBEKA-JOB-DEV/skyl/gateway`	1.25	go-chi/chi, skyl/otelThe optional HTTP service. Importing the core library never pulls in chi.
otel	`github.com/BAGOMBEKA-JOB-DEV/skyl/otel`	1.25	go.opentelemetry.io/otelOpenTelemetry instrumentation. Nobody who does not want it pays for it.

gateway exposes skyl over HTTP so non-Go services can reach models through one audited egress point. otel turns skyl's hook events into OpenTelemetry spans and metrics. Both are separate modules for the same reason as Anthropic: chi and the OpenTelemetry SDK are real dependency graphs, and someone importing a library should get a library.

Terminal

go get github.com/BAGOMBEKA-JOB-DEV/skyl/gateway
go get github.com/BAGOMBEKA-JOB-DEV/skyl/otel

Which Go version do I need?#

The floors differ, and they are not arbitrary — since Go 1.21 the go directive is a hard requirement rather than a suggestion, so each module declares the floor its dependencies actually set.

If you install…	You need
just the core library	Go 1.22
core + provider/anthropic	Go 1.24
core + gateway or otel	Go 1.25

Check yours:

Terminal

go version

Verifying the install#

You do not need a credential to check that it works. Run the sandbox in one terminal:

Terminal

go run github.com/BAGOMBEKA-JOB-DEV/skyl/cmd/skyl-sandbox

Then run this program:

verify/main.goCompiles

package main

import (
	"context"
	"fmt"
	"log"

	"github.com/BAGOMBEKA-JOB-DEV/skyl"
	"github.com/BAGOMBEKA-JOB-DEV/skyl/provider/openai"
)

func main() {
	client := skyl.New(openai.New("sandbox-key",
		openai.WithBaseURL("http://127.0.0.1:8099/openai/v1")))

	resp, err := client.Complete(context.Background(), &skyl.Request{
		Model:     "gpt-5.6",
		MaxTokens: 64,
		Messages:  []skyl.Message{skyl.UserText("What is the capital of France?")},
	})
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(resp.Text())
}

package main

import (
	"context"
	"fmt"
	"log"

	"github.com/BAGOMBEKA-JOB-DEV/skyl"
	"github.com/BAGOMBEKA-JOB-DEV/skyl/provider/openai"
)

func main() {
	client := skyl.New(openai.New("sandbox-key",
		openai.WithBaseURL("http://127.0.0.1:8099/openai/v1")))

	resp, err := client.Complete(context.Background(), &skyl.Request{
		Model:     "gpt-5.6",
		MaxTokens: 64,
		Messages:  []skyl.Message{skyl.UserText("What is the capital of France?")},
	})
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(resp.Text())
}

Output

Paris

If that prints, your install is correct and your adapter is wired properly — without spending anything or provisioning a key.

Adding a real credential#

When you are ready, set the environment variable for whichever provider you plan to use:

Terminal

export ANTHROPIC_API_KEY=sk-ant-...
export OPENAI_API_KEY=sk-...
export GEMINI_API_KEY=...

skyl never reads these itself — it has no configuration layer and no environment-variable convention. You pass the key to the provider constructor, which means the key's lifetime and source are entirely yours to control. See Credentials and Environment.

Recap

go get github.com/BAGOMBEKA-JOB-DEV/skyl — core library, Go 1.22, zero dependencies.
provider/anthropic is a separate module needing Go 1.24, because it wraps the official SDK.
openai, gemini and openaicompat ship inside the core module and cost you nothing.
gateway and otel are optional modules requiring Go 1.25.
The sandbox lets you verify the install with no API key and no cost.
skyl reads no environment variables of its own; you pass credentials to the constructor.

Try out some challenges

Each of these is solvable with what this page covered. Run them against the sandbox — no API key needed.

Prove the dependency claim

After go get github.com/BAGOMBEKA-JOB-DEV/skyl, confirm for yourself that the core module pulls in nothing external.

Show hint

go list can print a module's requirements without you reading go.mod.

Show solution

go list -m all | grep -v '^github.com/BAGOMBEKA-JOB-DEV/skyl'

go list -m all | grep -v '^github.com/BAGOMBEKA-JOB-DEV/skyl'

In a project whose only dependency is skyl, this prints your own module and nothing else. Add provider/anthropic and run it again to see the difference — that difference is exactly what ADR-0006 is protecting you from.

Point the verifier at a different sandbox mount

The program above talks to the openai mount. Change it to use the gemini adapter against the Gemini mount instead.

Show hint

Each mount has its own base URL and its own model catalogue. The sandbox serves gemini-3.6-flash, not gpt-5.6.

Show solution

goCompiles

client := skyl.New(gemini.New("sandbox-key",
	gemini.WithBaseURL("http://127.0.0.1:8099/gemini/v1beta")))

resp, err := client.Complete(context.Background(), &skyl.Request{
	Model:     "gemini-3.6-flash",
	MaxTokens: 64,
	Messages:  []skyl.Message{skyl.UserText("What is the capital of France?")},
})

client := skyl.New(gemini.New("sandbox-key",
	gemini.WithBaseURL("http://127.0.0.1:8099/gemini/v1beta")))

resp, err := client.Complete(context.Background(), &skyl.Request{
	Model:     "gemini-3.6-flash",
	MaxTokens: 64,
	Messages:  []skyl.Message{skyl.UserText("What is the capital of France?")},
})

Note that only the constructor and the model string changed — the Request, the call, and the response handling are identical. That is the whole argument for skyl in four lines.