diff --git a/backend/git.go b/backend/git.go
index e5135ea2..24854952 100644
--- a/backend/git.go
+++ b/backend/git.go
@@ -32,6 +32,7 @@ import (
 	"github.com/go-git/go-git/v5/plumbing/transport/ssh"
 	"github.com/go-git/go-git/v5/storage/memory"
 	"github.com/kevinburke/ssh_config"
+	homedir "github.com/mitchellh/go-homedir"
 	"github.com/spf13/pflag"
 )
 
@@ -438,6 +439,10 @@ func buildAuths(ctx context.Context, url string) ([]ssh.AuthMethod, error) {
 
 	idFiles := sshConfig.GetAll(e.Host, "IdentityFile")
 	for _, idFile := range idFiles {
+		idFile, err := homedir.Expand(idFile)
+		if err != nil {
+			continue
+		}
 		logger := logger.WithField("identity_file", idFile)
 		publicKeyAuth, err := ssh.NewPublicKeysFromFile(e.User, idFile, "")
 		if err == nil {
diff --git a/docs/guide/contributing.md b/docs/guide/contributing.md
new file mode 100644
index 00000000..a4487d36
--- /dev/null
+++ b/docs/guide/contributing.md
@@ -0,0 +1,113 @@
+---
+description: Contributing to scrt — how to build from source, run tests, and verify changes locally.
+---
+
+# Contributing <!-- omit in toc -->
+
+- [Prerequisites](#prerequisites)
+- [Clone a fork of the Repository](#clone-a-fork-of-the-repository)
+- [Build](#build)
+- [Run Tests](#run-tests)
+- [Install Locally](#install-locally)
+- [Lint Docs](#lint-docs)
+- [Verify Your Changes](#verify-your-changes)
+
+## Prerequisites
+
+- Go >= 1.18
+- Git
+- SSH key configured for GitHub (if testing git storage)
+
+## Clone a fork of the Repository
+
+```bash
+git clone https://github.com/loderunner/scrt.git
+```
+
+```bash
+cd scrt
+```
+
+## Build
+
+**Compile without producing a binary** (useful for quick syntax/type checks):
+
+```bash
+go build ./...
+```
+
+**Build the binary:**
+
+```bash
+go build -o scrt .
+```
+
+The binary will be at `./scrt` in the repository root.
+
+## Run Tests
+
+```bash
+go test ./...
+```
+
+## Install Locally
+
+**Option A — Replace the Homebrew binary (macOS):**
+
+```bash
+cp scrt /opt/homebrew/bin/scrt
+```
+
+**Option B — Install to `$GOPATH/bin`:**
+
+```bash
+go install .
+```
+
+Make sure `$GOPATH/bin` is in your `$PATH`.
+
+## Lint Docs
+
+CI runs prettier and eslint on the `docs/` directory. Run the linter locally before pushing:
+
+```bash
+cd docs && npm run lint
+```
+
+**Auto-fix formatting issues:**
+
+```bash
+cd docs && npx prettier --write .
+```
+
+## Verify Your Changes
+
+**Quick smoke test with local storage:**
+
+```bash
+./scrt init --storage=local --password=test --local-path=test.scrt
+```
+
+```bash
+./scrt set --storage=local --password=test --local-path=test.scrt mykey "myvalue"
+```
+
+```bash
+./scrt get --storage=local --password=test --local-path=test.scrt mykey
+```
+
+**Test with git storage:**
+
+```bash
+./scrt init --storage=git \
+    --password=test \
+    --git-url=git@github.com:<user>/<repo>.git \
+    --git-path=store.scrt \
+    --verbose
+```
+
+**Clean up test artifacts:**
+
+```bash
+rm -f test.scrt
+```