diff --git a/.circleci/config.yml b/.circleci/config.yml
deleted file mode 100644
index b351548..0000000
--- a/.circleci/config.yml
+++ /dev/null
@@ -1,111 +0,0 @@
-version: 2
-
-jobs:
-  "golang-1.24":
-    docker:
-      - image: cimg/go:1.24
-    steps:
-      - checkout
-      - run: 'wget https://github.com/DataDog/zstd/files/2246767/mr.zip'
-      - run: 'unzip mr.zip'
-      - run: 'go build'
-      - run: 'PAYLOAD=`pwd`/mr go test -v'
-      - run: 'PAYLOAD=`pwd`/mr go test -bench .'
-  "golang-1.24-external-libzstd":
-    docker:
-      - image: cimg/go:1.24
-    steps:
-      - checkout
-      - run: 'sudo apt update'
-      - run: 'sudo apt install libzstd-dev'
-      - run: 'wget https://github.com/DataDog/zstd/files/2246767/mr.zip'
-      - run: 'unzip mr.zip'
-      - run: 'go build'
-      - run: 'PAYLOAD=`pwd`/mr go test -v'
-      - run: 'PAYLOAD=`pwd`/mr go test -bench .'
-  "golang-1.25":
-    docker:
-      - image: cimg/go:1.25
-    steps:
-      - checkout
-      - run: 'wget https://github.com/DataDog/zstd/files/2246767/mr.zip'
-      - run: 'unzip mr.zip'
-      - run: 'go build'
-      - run: 'PAYLOAD=`pwd`/mr go test -v'
-      - run: 'PAYLOAD=`pwd`/mr go test -bench .'
-  "golang-1.25-external-libzstd":
-    docker:
-      - image: cimg/go:1.25
-    steps:
-      - checkout
-      - run: 'sudo apt update'
-      - run: 'sudo apt install libzstd-dev'
-      - run: 'wget https://github.com/DataDog/zstd/files/2246767/mr.zip'
-      - run: 'unzip mr.zip'
-      - run: 'go build'
-      - run: 'PAYLOAD=`pwd`/mr go test -v'
-      - run: 'PAYLOAD=`pwd`/mr go test -bench .'
-  "golang-1.26":
-    docker:
-      - image: cimg/go:1.26
-    steps:
-      - checkout
-      - run: 'wget https://github.com/DataDog/zstd/files/2246767/mr.zip'
-      - run: 'unzip mr.zip'
-      - run: 'go build'
-      - run: 'PAYLOAD=`pwd`/mr go test -v'
-      - run: 'PAYLOAD=`pwd`/mr go test -bench .'
-  "golang-1.26-external-libzstd":
-    docker:
-      - image: cimg/go:1.26
-    steps:
-      - checkout
-      - run: 'sudo apt update'
-      - run: 'sudo apt install libzstd-dev'
-      - run: 'wget https://github.com/DataDog/zstd/files/2246767/mr.zip'
-      - run: 'unzip mr.zip'
-      - run: 'go build'
-      - run: 'PAYLOAD=`pwd`/mr go test -v'
-      - run: 'PAYLOAD=`pwd`/mr go test -bench .'
-  "golang-efence":
-    resource_class: xlarge
-    docker:
-      - image: cimg/go:1.26
-    steps:
-      - checkout
-      - run: 'wget https://github.com/DataDog/zstd/files/2246767/mr.zip'
-      - run: 'unzip mr.zip'
-      - run: 'go build'
-      - run: 'PAYLOAD=`pwd`/mr GODEBUG=efence=1 go test -v'
-  "golang-efence-external-libzstd":
-    resource_class: xlarge
-    docker:
-      - image: cimg/go:1.26
-    steps:
-      - checkout
-      - run: 'sudo apt update'
-      - run: 'sudo apt install libzstd-dev'
-      - run: 'wget https://github.com/DataDog/zstd/files/2246767/mr.zip'
-      - run: 'unzip mr.zip'
-      - run: 'go build -tags external_libzstd'
-      - run: 'PAYLOAD=`pwd`/mr GODEBUG=efence=1 go test -tags external_libzstd -v'
-  "golang-i386":
-    docker:
-      - image: 32bit/ubuntu:16.04
-    steps:
-      - checkout
-      - run: 'linux32 --32bit i386 ./travis_test_32.sh'
-
-workflows:
-  version: 2
-  build:
-    jobs:
-      - "golang-1.24"
-      - "golang-1.24-external-libzstd"
-      - "golang-1.25"
-      - "golang-1.25-external-libzstd"
-      - "golang-1.26"
-      - "golang-1.26-external-libzstd"
-      - "golang-efence"
-      - "golang-efence-external-libzstd"
-      - "golang-i386"
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..8cdfcd2
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,118 @@
+name: CI
+
+on:
+  push:
+    branches: [main, "1.x"]
+  pull_request:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: ci-${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: ${{ github.event_name == 'pull_request' }}
+
+jobs:
+  build-test:
+    name: golang-${{ matrix.go-version }}${{ matrix.external-libzstd && '-external-libzstd' || '' }}
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        go-version: ["1.24", "1.25", "1.26"]
+        external-libzstd: [false, true]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+      - name: Setup Go
+        uses: actions/setup-go@4a3601121dd01d1626a1e23e37211e3254c1c06c # v6.4.0
+        with:
+          go-version: ${{ matrix.go-version }}
+      - name: Install libzstd-dev
+        if: ${{ matrix.external-libzstd }}
+        run: sudo apt-get update && sudo apt-get install -y libzstd-dev
+      - name: Download payload
+        run: |
+          wget https://github.com/DataDog/zstd/files/2246767/mr.zip
+          unzip mr.zip
+      - name: Build
+        run: go build
+      - name: Test
+        run: PAYLOAD="$(pwd)/mr" go test -v
+      - name: Bench
+        run: PAYLOAD="$(pwd)/mr" go test -bench .
+
+  efence:
+    name: golang-efence
+    # CircleCI ran this on resource_class: xlarge (8 vCPU). GitHub-hosted
+    # ubuntu-latest is 4 vCPU / 16 GB; if memory pressure or runtime becomes
+    # an issue under GODEBUG=efence=1, switch to a larger runner label.
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+      - name: Setup Go
+        uses: actions/setup-go@4a3601121dd01d1626a1e23e37211e3254c1c06c # v6.4.0
+        with:
+          go-version: "1.26"
+      - name: Download payload
+        run: |
+          wget https://github.com/DataDog/zstd/files/2246767/mr.zip
+          unzip mr.zip
+      - name: Build
+        run: go build
+      - name: Test (efence)
+        env:
+          GODEBUG: efence=1
+        run: PAYLOAD="$(pwd)/mr" go test -v
+
+  efence-external-libzstd:
+    name: golang-efence-external-libzstd
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+      - name: Setup Go
+        uses: actions/setup-go@4a3601121dd01d1626a1e23e37211e3254c1c06c # v6.4.0
+        with:
+          go-version: "1.26"
+      - name: Install libzstd-dev
+        run: sudo apt-get update && sudo apt-get install -y libzstd-dev
+      - name: Download payload
+        run: |
+          wget https://github.com/DataDog/zstd/files/2246767/mr.zip
+          unzip mr.zip
+      - name: Build
+        run: go build -tags external_libzstd
+      - name: Test (efence)
+        env:
+          GODEBUG: efence=1
+        run: PAYLOAD="$(pwd)/mr" go test -tags external_libzstd -v
+
+  i386:
+    name: golang-i386
+    runs-on: ubuntu-latest
+    env:
+      GOARCH: "386"
+      CGO_ENABLED: "1"
+      CC: "gcc -m32"
+    steps:
+      - name: Checkout
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+      - name: Setup Go
+        uses: actions/setup-go@4a3601121dd01d1626a1e23e37211e3254c1c06c # v6.4.0
+        with:
+          go-version: "1.26"
+      - name: Install 32-bit toolchain
+        run: sudo apt-get update && sudo apt-get install -y gcc-multilib libc6-dev-i386
+      - name: Download payload
+        run: |
+          wget https://github.com/DataDog/zstd/files/2246767/mr.zip
+          unzip mr.zip
+      - name: Build (i386)
+        run: go build
+      - name: Test (i386)
+        env:
+          DISABLE_BIG_TESTS: "1"
+          PAYLOAD: ${{ github.workspace }}/mr
+        run: go test -v
diff --git a/travis_test_32.sh b/travis_test_32.sh
deleted file mode 100755
index 264ca06..0000000
--- a/travis_test_32.sh
+++ /dev/null
@@ -1,19 +0,0 @@
-#!/bin/bash
-# Get utilities
-#yum -y -q -e 0 install wget tar unzip gcc
-apt-get update
-apt-get -y install wget tar unzip gcc
-
-# Get Go
-wget -q https://dl.google.com/go/go1.13.linux-386.tar.gz
-tar -C /usr/local -xzf go1.13.linux-386.tar.gz
-export PATH=$PATH:/usr/local/go/bin
-
-# Get payload
-wget -q https://github.com/DataDog/zstd/files/2246767/mr.zip
-unzip mr.zip
-
-# Build and run tests
-go build
-DISABLE_BIG_TESTS=1 PAYLOAD=$(pwd)/mr go test -v
-DISABLE_BIG_TESTS=1 PAYLOAD=$(pwd)/mr go test -bench .