fix: reduce CI/release build times with cargo and Docker caching. Add Swatinem/rust-cache@v2 to all CI and release workflow jobs. Add Docker BuildKit GHA layer caching (cache-from/cache-to type=gha) to both docker/build-push-action steps. Replace Dockerfile stub-build trick with BuildKit --mount=type=cache for cargo registry and target directory.

Author: mikkeldamsgaard

.github/workflows/ci.yml

@@ -14,20 +14,23 @@ jobs:
       - uses: dtolnay/rust-toolchain@stable
         with:
           components: clippy, rustfmt
+      - uses: Swatinem/rust-cache@v2
       - run: cargo fmt --check
       - run: cargo clippy -- -D warnings
   test:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@stable
+      - uses: Swatinem/rust-cache@v2
       - run: cargo test --all
   build:
     runs-on: ubuntu-latest
     needs: [lint, test]
     steps:
       - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@stable
+      - uses: Swatinem/rust-cache@v2
       - run: cargo build --release
       - uses: actions/upload-artifact@v4
         with:

.github/workflows/release.yml

@@ -13,6 +13,7 @@ jobs:
     steps:
       - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@stable
+      - uses: Swatinem/rust-cache@v2
       - run: cargo test --all
       - uses: docker/setup-qemu-action@v3
       - uses: docker/setup-buildx-action@v3
@@ -34,6 +35,8 @@ jobs:
           tags: |
             ghcr.io/kitstream/initium:${{ steps.version.outputs.VERSION }}
             ghcr.io/kitstream/initium:latest
+          cache-from: type=gha,scope=docker-main
+          cache-to: type=gha,mode=max,scope=docker-main
           sbom: true
           provenance: true
       - uses: docker/build-push-action@v6
@@ -47,5 +50,7 @@ jobs:
           tags: |
             ghcr.io/kitstream/initium-jyq:${{ steps.version.outputs.VERSION }}
             ghcr.io/kitstream/initium-jyq:latest
+          cache-from: type=gha,scope=docker-jyq
+          cache-to: type=gha,mode=max,scope=docker-jyq
           sbom: true
           provenance: true

CHANGELOG.md

@@ -7,6 +7,18 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Fixed
+- Added Cargo dependency caching (`Swatinem/rust-cache@v2`) to all CI and release workflow jobs for faster builds
+- Added Docker BuildKit layer caching (`type=gha`) to release workflow for both main and jyq image builds
+- Replaced Dockerfile stub-build caching layer with BuildKit `--mount=type=cache` for cargo registry and target directory, enabling cross-build cache reuse
+
+### Changed
+- Replaced `regex` crate with manual envsubst parser in render module for smaller binary
+- Replaced `chrono` crate with `std::time::SystemTime` and Hinnant's civil calendar algorithm in logging module
+- Switched rustls from default crypto backends (aws-lc-rs + ring) to ring-only
+- Disabled ureq default features (gzip/brotli) to reduce dependency tree
+- Database drivers (sqlite, postgres, mysql) are now optional Cargo features (all enabled by default); build with `--no-default-features --features sqlite` for minimal binary
+
 ### Removed
 - Seed schema version 1 (flat `seed_sets` without phases): all seed specs now use phase-based structure
 - `version` field from seed spec schema: no longer required or accepted

Cargo.lock

@@ -9,20 +9,24 @@ license = "Apache-2.0"
 name = "initium"
 path = "src/main.rs"
 
+[features]
+default = ["sqlite", "postgres", "mysql"]
+sqlite = ["dep:rusqlite"]
+postgres = ["dep:postgres"]
+mysql = ["dep:mysql"]
+
 [dependencies]
 clap = { version = "4", features = ["derive"] }
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 serde_yaml = "0.9"
-regex = "1"
-chrono = { version = "0.4", default-features = false, features = ["clock"] }
 rand = "0.8"
-ureq = { version = "2", features = ["tls"] }
-rustls = "0.23"
+ureq = { version = "2", features = ["tls"], default-features = false }
+rustls = { version = "0.23", default-features = false, features = ["ring", "logging", "std", "tls12"] }
 minijinja = "2"
-rusqlite = { version = "0.31", features = ["bundled"] }
-postgres = "0.19"
-mysql = "25"
+rusqlite = { version = "0.31", features = ["bundled"], optional = true }
+postgres = { version = "0.19", optional = true }
+mysql = { version = "25", optional = true }
 
 [dev-dependencies]
 tempfile = "3"

Cargo.toml

@@ -3,9 +3,9 @@ ARG VERSION=dev
 RUN apk add --no-cache musl-dev openssl-dev openssl-libs-static perl
 WORKDIR /src
 COPY Cargo.toml Cargo.lock ./
-RUN mkdir src && echo 'fn main() {}' > src/main.rs && cargo build --release && rm -rf src
 COPY . .
-RUN touch src/main.rs && \
+RUN --mount=type=cache,target=/usr/local/cargo/registry \
+    --mount=type=cache,target=/src/target \
     cargo build --release && \
     cp target/release/initium /initium
 FROM scratch

Dockerfile

@@ -44,7 +44,7 @@ kubectl apply -f https://raw.githubusercontent.com/kitstream/initium/main/exampl
 | **Structured logging**    | `echo` statements                | JSON or text with timestamps       |
 | **Security**              | Runs as root, full shell         | Non-root, no shell, read-only FS   |
 | **Secret handling**       | Easily leaked in logs            | Automatic redaction                |
-| **Multiple tools**        | Install curl, netcat, psql…      | Single 2MB image                   |
+| **Multiple tools**        | Install curl, netcat, psql…      | Single small image                 |
 | **Reproducibility**       | Shell differences across distros | Single Rust binary, `FROM scratch` |
 | **Vulnerability surface** | Full OS + shell utils            | Zero OS packages                   |
 
@@ -78,6 +78,27 @@ initium wait-for \
 initium wait-for --target https://vault:8200/v1/sys/health --insecure-tls
 ```
 
+## Cargo Features
+
+Database drivers are optional Cargo features, all enabled by default. Disable unused drivers for a smaller binary:
+
+```bash
+# All drivers (default)
+cargo build --release
+
+# PostgreSQL + SQLite only (no MySQL)
+cargo build --release --no-default-features --features postgres,sqlite
+
+# SQLite only (smallest binary)
+cargo build --release --no-default-features --features sqlite
+```
+
+| Feature    | Default | Description        |
+| ---------- | ------- | ------------------ |
+| `sqlite`   | ✅       | SQLite driver      |
+| `postgres` | ✅       | PostgreSQL driver  |
+| `mysql`    | ✅       | MySQL/MariaDB driver |
+
 ## Helm Chart
 
 The Helm chart makes it easy to inject Initium initContainers into your deployments.

README.md

@@ -3,9 +3,9 @@ ARG VERSION=dev
 RUN apk add --no-cache musl-dev openssl-dev openssl-libs-static perl
 WORKDIR /src
 COPY Cargo.toml Cargo.lock ./
-RUN mkdir src && echo 'fn main() {}' > src/main.rs && cargo build --release && rm -rf src
 COPY . .
-RUN touch src/main.rs && \
+RUN --mount=type=cache,target=/usr/local/cargo/registry \
+    --mount=type=cache,target=/src/target \
     cargo build --release && \
     cp target/release/initium /initium
 FROM alpine:3.21