diff --git a/README.md b/README.md
index 36d8180..1b7f750 100644
--- a/README.md
+++ b/README.md
@@ -90,6 +90,10 @@ Tool execution uses the configured native Landlock sandbox. Operations requiring
 
 Persistent memory is provided by [OptMem](https://github.com/VictorTaelin/OptMem) through `memory_recall` and `memory_remember`; Ollie does not maintain a second memory-file format. History management renders context, tracks usage and cost, caps oversized tool output, and compacts older material when necessary.
 
+### Future work: portable toolsrv hosts
+
+`toolsrv` should be extensible to other host operating systems so Ollie tools remain useful on as many systems as possible. This includes the host-specific execution, filesystem, process, networking, and sandbox integrations required on BSD systems, macOS, and other Unix-like platforms. `olliesrv` may remain Linux-specific; its role is the agent runtime and orchestration service, while `toolsrv` is the platform-dependent execution boundary. WSL2 should work through its Linux kernel and use the existing Linux implementation.
+
 ## Frontends
 
 Shell scripts, Acme, KDE components, and other clients create sessions, write prompts, and read files such as `chat`, `statewait`, `context`, and `feed`. They do not embed provider, tool, or agent-loop logic.
diff --git a/cmd/toolsrv/internal/exec/exec.go b/cmd/toolsrv/internal/exec/exec.go
index 43fdb67..ec31fd2 100644
--- a/cmd/toolsrv/internal/exec/exec.go
+++ b/cmd/toolsrv/internal/exec/exec.go
@@ -125,7 +125,7 @@ func executeSandboxed(ctx context.Context, toolPath, stdinData, cwd string, envE
 		}
 	}()
 
-	var sandboxCfg *sandbox.Config
+	var sandboxCfg sandbox.Sandbox
 	if !yolo {
 		cfgPath := filepath.Join(util.CfgDir(), "sandbox.yaml")
 		f, err := os.Open(cfgPath)
@@ -133,11 +133,11 @@ func executeSandboxed(ctx context.Context, toolPath, stdinData, cwd string, envE
 			return "", fmt.Errorf("sandbox config not found: %w", err)
 		}
 		defer f.Close()
-		var loadErr error
-		sandboxCfg, loadErr = sandbox.LoadSandbox(f)
+		cfg, loadErr := sandbox.LoadSandbox(f)
 		if loadErr != nil {
 			return "", loadErr
 		}
+		sandboxCfg = cfg
 	}
 
 	if timeout > 0 {
@@ -176,7 +176,7 @@ func executeSandboxed(ctx context.Context, toolPath, stdinData, cwd string, envE
 	if yolo {
 		cmd = osExec.CommandContext(ctx, interpreter[0], interpreter[1:]...)
 	} else {
-		wrapped, wrapErr := sandbox.NativeCommand(sandboxCfg, interpreter, cwd, envMap)
+		wrapped, wrapErr := sandboxCfg.Command(interpreter, cwd, envMap)
 		if wrapErr != nil {
 			return "", wrapErr
 		}
diff --git a/cmd/toolsrv/internal/sandbox/config.go b/cmd/toolsrv/internal/sandbox/config.go
index a9c1503..fc23f9c 100644
--- a/cmd/toolsrv/internal/sandbox/config.go
+++ b/cmd/toolsrv/internal/sandbox/config.go
@@ -13,6 +13,11 @@ import (
 	"gopkg.in/yaml.v3"
 )
 
+// Sandbox prepares a command for restricted execution.
+type Sandbox interface {
+	Command(originalCmd []string, cwd string, env map[string]string) ([]string, error)
+}
+
 // Config represents the sandbox configuration
 type Config struct {
 	General    GeneralConfig    `yaml:"general"`
diff --git a/cmd/toolsrv/internal/sandbox/wrapper.go b/cmd/toolsrv/internal/sandbox/wrapper.go
index 416d956..a01eb93 100644
--- a/cmd/toolsrv/internal/sandbox/wrapper.go
+++ b/cmd/toolsrv/internal/sandbox/wrapper.go
@@ -6,8 +6,8 @@ import (
 	"os"
 )
 
-// NativeCommand encodes a native sandbox helper invocation.
-func NativeCommand(cfg *Config, originalCmd []string, cwd string, env map[string]string) ([]string, error) {
+// Command encodes a native sandbox helper invocation.
+func (cfg *Config) Command(originalCmd []string, cwd string, env map[string]string) ([]string, error) {
 	envCopy := make(map[string]string, len(env))
 	for k, v := range env {
 		envCopy[k] = v