diff --git a/src/opencode/devcontainer-feature.json b/src/opencode/devcontainer-feature.json
index e71927d..fe287ac 100644
--- a/src/opencode/devcontainer-feature.json
+++ b/src/opencode/devcontainer-feature.json
@@ -1,7 +1,7 @@
 {
 	"name": "opencode CLI",
 	"id": "opencode",
-	"version": "0.3.6",
+	"version": "0.3.7",
 	"description": "Installs the opencode AI coding agent CLI and ensures volume-mounted data directories are owned by the correct user.",
 	"documentationURL": "https://opencode.ai",
 	"options": {
diff --git a/src/opencode/postStartCommand.sh b/src/opencode/postStartCommand.sh
index 0a34e95..99dd1a7 100755
--- a/src/opencode/postStartCommand.sh
+++ b/src/opencode/postStartCommand.sh
@@ -5,6 +5,60 @@ echo_prefix="[opencode-poststart]"
 
 autoupdate="${AUTOUPDATE:-true}"
 
+# ensure volume-mounted config directories exist and have correct ownership
+# resolve the user and home matching where install.sh placed the config
+TARGET_USER=""
+TARGET_HOME="${HOME:-}"
+
+if [ -n "$TARGET_HOME" ]; then
+  TARGET_USER="$(getent passwd | awk -F: -v h="$TARGET_HOME" '$6 == h {print $1; exit}')" || true
+fi
+
+if [ -z "$TARGET_USER" ]; then
+  user="${_REMOTE_USER:-${USERNAME:-}}"
+  valid_user="$(getent passwd | awk -F: '$3 >= 1000 && $1 !~ /^(nobody|nfsnobody|daemon)$/ {print $1; exit 0}')" || true
+  [ -z "$valid_user" ] && valid_user="root"
+  if [ -n "$user" ]; then
+    user_shell="$(getent passwd "$user" 2>/dev/null | cut -d: -f7)" || true
+    case "$user_shell" in
+      */nologin|*/false|"")
+        user="$valid_user"
+        ;;
+    esac
+  fi
+  [ -z "$user" ] && user="$valid_user"
+  TARGET_USER="$user"
+  TARGET_HOME="$(getent passwd "$TARGET_USER" 2>/dev/null | cut -d: -f6)"
+  [ -z "$TARGET_HOME" ] && TARGET_HOME="/home/$TARGET_USER"
+fi
+
+# recreate directories masked by volume mounts
+mkdir -p "${TARGET_HOME}/.config/opencode"
+mkdir -p "${TARGET_HOME}/.local/share/opencode"
+mkdir -p "${TARGET_HOME}/.local/state/opencode"
+
+# ensure opencode.json with lsp config exists
+opencode_config="${TARGET_HOME}/.config/opencode/opencode.json"
+if [ -f "$opencode_config" ]; then
+  if ! jq -e '.lsp' "$opencode_config" >/dev/null 2>&1; then
+    jq '. + {"lsp": {}}' "$opencode_config" > "${opencode_config}.tmp" && mv "${opencode_config}.tmp" "$opencode_config"
+    echo "$echo_prefix added 'lsp' key to existing opencode.json"
+  fi
+else
+  cat > "$opencode_config" <<'EOF'
+{
+  "$schema": "https://opencode.ai/config.json",
+  "lsp": {}
+}
+EOF
+  echo "$echo_prefix created opencode.json with LSP enabled"
+fi
+
+chown -R "${TARGET_USER}:${TARGET_USER}" \
+  "${TARGET_HOME}/.config/opencode" \
+  "${TARGET_HOME}/.local/share/opencode" \
+  "${TARGET_HOME}/.local/state/opencode" 2>/dev/null || true
+
 if ! command -v opencode >/dev/null 2>&1; then
     echo "$echo_prefix opencode not found, installing..."
     curl -fsSL https://opencode.ai/install | bash
diff --git a/test/opencode/autoupdate_disabled.sh b/test/opencode/autoupdate_disabled.sh
index 4a0fc3b..97e709c 100644
--- a/test/opencode/autoupdate_disabled.sh
+++ b/test/opencode/autoupdate_disabled.sh
@@ -15,4 +15,12 @@ check "opencode.json has lsp key" jq -e '.lsp' "$OPENCODE_CONFIG"
 
 check "opencode.json lsp is empty" test "$(jq '.lsp | length' "$OPENCODE_CONFIG")" -eq 0
 
+# test postStartCommand recreates config when missing (volume mount case)
+OPENCODE_CONFIG_BAK="$OPENCODE_CONFIG"
+rm -f "$OPENCODE_CONFIG_BAK"
+AUTOUPDATE=false bash /usr/local/share/devcontainer-features/opencode-postStartCommand.sh || true
+check "postStartCommand recreates opencode.json" test -f "$OPENCODE_CONFIG_BAK"
+check "recreated opencode.json has lsp key" jq -e '.lsp' "$OPENCODE_CONFIG_BAK"
+check "recreated opencode.json lsp is empty" test "$(jq '.lsp | length' "$OPENCODE_CONFIG_BAK")" -eq 0
+
 reportResults
\ No newline at end of file
diff --git a/test/opencode/autoupdate_enabled.sh b/test/opencode/autoupdate_enabled.sh
index 3b27772..861436a 100644
--- a/test/opencode/autoupdate_enabled.sh
+++ b/test/opencode/autoupdate_enabled.sh
@@ -17,4 +17,12 @@ check "opencode.json has lsp key" jq -e '.lsp' "$OPENCODE_CONFIG"
 
 check "opencode.json lsp is empty" test "$(jq '.lsp | length' "$OPENCODE_CONFIG")" -eq 0
 
+# test postStartCommand recreates config when missing (volume mount case)
+OPENCODE_CONFIG_BAK="$OPENCODE_CONFIG"
+rm -f "$OPENCODE_CONFIG_BAK"
+AUTOUPDATE=false bash /usr/local/share/devcontainer-features/opencode-postStartCommand.sh || true
+check "postStartCommand recreates opencode.json" test -f "$OPENCODE_CONFIG_BAK"
+check "recreated opencode.json has lsp key" jq -e '.lsp' "$OPENCODE_CONFIG_BAK"
+check "recreated opencode.json lsp is empty" test "$(jq '.lsp | length' "$OPENCODE_CONFIG_BAK")" -eq 0
+
 reportResults
\ No newline at end of file
diff --git a/test/opencode/custom_username.sh b/test/opencode/custom_username.sh
index d249541..74d8104 100755
--- a/test/opencode/custom_username.sh
+++ b/test/opencode/custom_username.sh
@@ -17,4 +17,12 @@ check "opencode.json has lsp key" jq -e '.lsp' "$OPENCODE_CONFIG"
 
 check "opencode.json lsp is empty" test "$(jq '.lsp | length' "$OPENCODE_CONFIG")" -eq 0
 
+# test postStartCommand recreates config when missing (volume mount case)
+OPENCODE_CONFIG_BAK="$OPENCODE_CONFIG"
+rm -f "$OPENCODE_CONFIG_BAK"
+AUTOUPDATE=false bash /usr/local/share/devcontainer-features/opencode-postStartCommand.sh || true
+check "postStartCommand recreates opencode.json" test -f "$OPENCODE_CONFIG_BAK"
+check "recreated opencode.json has lsp key" jq -e '.lsp' "$OPENCODE_CONFIG_BAK"
+check "recreated opencode.json lsp is empty" test "$(jq '.lsp | length' "$OPENCODE_CONFIG_BAK")" -eq 0
+
 reportResults
diff --git a/test/opencode/default.sh b/test/opencode/default.sh
index d249541..74d8104 100755
--- a/test/opencode/default.sh
+++ b/test/opencode/default.sh
@@ -17,4 +17,12 @@ check "opencode.json has lsp key" jq -e '.lsp' "$OPENCODE_CONFIG"
 
 check "opencode.json lsp is empty" test "$(jq '.lsp | length' "$OPENCODE_CONFIG")" -eq 0
 
+# test postStartCommand recreates config when missing (volume mount case)
+OPENCODE_CONFIG_BAK="$OPENCODE_CONFIG"
+rm -f "$OPENCODE_CONFIG_BAK"
+AUTOUPDATE=false bash /usr/local/share/devcontainer-features/opencode-postStartCommand.sh || true
+check "postStartCommand recreates opencode.json" test -f "$OPENCODE_CONFIG_BAK"
+check "recreated opencode.json has lsp key" jq -e '.lsp' "$OPENCODE_CONFIG_BAK"
+check "recreated opencode.json lsp is empty" test "$(jq '.lsp | length' "$OPENCODE_CONFIG_BAK")" -eq 0
+
 reportResults
diff --git a/test/opencode/specific_version.sh b/test/opencode/specific_version.sh
index 872d49c..1dd0182 100755
--- a/test/opencode/specific_version.sh
+++ b/test/opencode/specific_version.sh
@@ -21,4 +21,12 @@ check "opencode.json has lsp key" jq -e '.lsp' "$OPENCODE_CONFIG"
 
 check "opencode.json lsp is empty" test "$(jq '.lsp | length' "$OPENCODE_CONFIG")" -eq 0
 
+# test postStartCommand recreates config when missing (volume mount case)
+OPENCODE_CONFIG_BAK="$OPENCODE_CONFIG"
+rm -f "$OPENCODE_CONFIG_BAK"
+AUTOUPDATE=false bash /usr/local/share/devcontainer-features/opencode-postStartCommand.sh || true
+check "postStartCommand recreates opencode.json" test -f "$OPENCODE_CONFIG_BAK"
+check "recreated opencode.json has lsp key" jq -e '.lsp' "$OPENCODE_CONFIG_BAK"
+check "recreated opencode.json lsp is empty" test "$(jq '.lsp | length' "$OPENCODE_CONFIG_BAK")" -eq 0
+
 reportResults
diff --git a/test/opencode/test.sh b/test/opencode/test.sh
index 5c30acb..3e2f4ae 100755
--- a/test/opencode/test.sh
+++ b/test/opencode/test.sh
@@ -19,4 +19,12 @@ check "opencode.json has lsp key" jq -e '.lsp' "$OPENCODE_CONFIG"
 
 check "opencode.json lsp is empty" test "$(jq '.lsp | length' "$OPENCODE_CONFIG")" -eq 0
 
+# test postStartCommand recreates config when missing (volume mount case)
+OPENCODE_CONFIG_BAK="$OPENCODE_CONFIG"
+rm -f "$OPENCODE_CONFIG_BAK"
+AUTOUPDATE=false bash /usr/local/share/devcontainer-features/opencode-postStartCommand.sh || true
+check "postStartCommand recreates opencode.json" test -f "$OPENCODE_CONFIG_BAK"
+check "recreated opencode.json has lsp key" jq -e '.lsp' "$OPENCODE_CONFIG_BAK"
+check "recreated opencode.json lsp is empty" test "$(jq '.lsp | length' "$OPENCODE_CONFIG_BAK")" -eq 0
+
 reportResults
diff --git a/wiki/architecture.md b/wiki/architecture.md
index e423018..43c91c2 100644
--- a/wiki/architecture.md
+++ b/wiki/architecture.md
@@ -8,8 +8,15 @@
 └── validate.yaml      # Validate features
 src/                    # Feature implementations
 ├── opencode/
+│   ├── devcontainer-feature.json  # metadata + options
+│   ├── install.sh                 # build-time setup
+│   ├── postStartCommand.sh        # runtime config (volume resilience)
+│   ├── README.md
+│   └── NOTES.md
+├── agents-workspace/
 │   ├── devcontainer-feature.json
 │   ├── install.sh
+│   ├── postStartCommand.sh
 │   ├── README.md
 │   └── NOTES.md
 └── agency-agents/
diff --git a/wiki/conventions.md b/wiki/conventions.md
index c9246cc..24e4f04 100644
--- a/wiki/conventions.md
+++ b/wiki/conventions.md
@@ -4,7 +4,14 @@
 
 Each feature lives in `src/<feature>/` with:
 - `devcontainer-feature.json` — metadata + options
-- `install.sh` — entrypoint script
+- `install.sh` — entrypoint script (build time)
+- `postStartCommand.sh` — post-start script (runtime)
+
+## Volume Mount Resilience
+
+Config files and directories that must survive Docker volume mounts must be created or ensured in `postStartCommand.sh`, not only in `install.sh`. Volumes mounted at runtime replace build-time directories; `postStartCommand.sh` runs after volumes are mounted and can recreate any missing state.
+
+`install.sh` may still create these files at build time for the non-volume case, but `postStartCommand.sh` must be the authoritative source for runtime state.
 
 ## Options
 
diff --git a/wiki/decisions/poststart-config-creation.md b/wiki/decisions/poststart-config-creation.md
new file mode 100644
index 0000000..26bed9a
--- /dev/null
+++ b/wiki/decisions/poststart-config-creation.md
@@ -0,0 +1,22 @@
+---
+title: PostStart config creation for volume mount resilience
+date: 2026-05-26
+status: accepted
+---
+
+## Context
+
+The `opencode` feature creates `~/.config/opencode/opencode.json` (with `lsp: {}`) during `install.sh` at build time. When a Docker volume is mounted at `/home/vscode/.config/opencode`, the volume starts empty at runtime and hides the build-time file. The `postStartCommand.sh` did not recreate it, so LSP servers remained unconfigured.
+
+The `agents-workspace` feature demonstrates the correct pattern: `install.sh` only copies the postStart script, and all actual setup happens in `postStartCommand.sh` at runtime.
+
+## Decision
+
+Move `opencode.json` creation (and directory ownership fixes) from `install.sh` into `postStartCommand.sh`, which runs every container start. `install.sh` still creates the file at build time (harmless for non-volume cases), but `postStartCommand.sh` guarantees it exists even when a volume replaces the directory.
+
+## Consequences
+
+- Volume mounts no longer break LSP server configuration
+- `postStartCommand.sh` is idempotent — if the file exists with `lsp`, it skips creation; if it exists without `lsp`, it merges it in
+- Ownership is corrected at runtime in case the volume changes UID/GID mappings
+- Tests now validate that `postStartCommand.sh` can recreate the config independently
diff --git a/wiki/features.md b/wiki/features.md
index 3022250..cf1d1d0 100644
--- a/wiki/features.md
+++ b/wiki/features.md
@@ -2,13 +2,17 @@
 
 ## opencode
 
-Installs opencode CLI and fixes volume-mounted directory permissions.
+Installs opencode CLI and ensures volume-mounted config directories are writable.
 
 Options:
 - `username` (default: _REMOTE_USER) — user to install for
 - `version` (default: empty/latest) — install specific version
 - `autoupdate` (default: true) — auto-upgrade on container start
 
+Behavior:
+- `install.sh` installs the CLI, creates directories, writes `~/.config/opencode/opencode.json` with `lsp: {}`, and generates a fix-permissions script.
+- `postStartCommand.sh` ensures `opencode.json` exists at every start (critical when `~/.config/opencode` is a volume mount), installing opencode if missing and running autoupgrade when enabled.
+
 Idempotency: marker uses version if specified, else "latest"
 
 ## agency-agents
diff --git a/wiki/index.md b/wiki/index.md
index 1d37162..c05ad09 100644
--- a/wiki/index.md
+++ b/wiki/index.md
@@ -1,10 +1,11 @@
 # Wiki
 
 - [architecture.md](architecture.md) — project structure and feature layout
-- [conventions.md](conventions.md) — feature structure and option patterns
+- [conventions.md](conventions.md) — feature structure, option patterns, volume mount resilience
 - [features.md](features.md) — available features and their purpose
 - [publishing.md](publishing.md) — release workflow and GHCR publishing
 - [testing.md](testing.md) — testing commands and CLI usage
+- [decisions/poststart-config-creation.md](decisions/poststart-config-creation.md) — runtime config creation for volume mount support
 
 ## Operations