Merge pull request #210 from aykhans/feat/nix-flake-packaging

Add nix flake packaging

.github/workflows/lint.yaml

@@ -13,10 +13,10 @@ jobs:
     name: lint
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v7
-      - uses: actions/setup-go@v6
+      - uses: actions/setup-go@v7
         with:
-          go-version: 1.26.2
+          go-version: 1.26.5
       - name: go fix
         run: |
           go fix ./...
@@ -24,4 +24,4 @@ jobs:
       - name: golangci-lint
         uses: golangci/golangci-lint-action@v9
         with:
-          version: v2.11.4
+          version: v2.12.2

.github/workflows/release.yaml

@@ -27,7 +27,7 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
         with:
           ref: ${{ inputs.tag || github.ref }}
 
@@ -35,11 +35,11 @@ jobs:
         run: |
           echo "VERSION=$(git describe --tags --always)" >> $GITHUB_ENV
           echo "GIT_COMMIT=$(git rev-parse HEAD)" >> $GITHUB_ENV
-          echo "GO_VERSION=1.26.2" >> $GITHUB_ENV
+          echo "GO_VERSION=1.26.5" >> $GITHUB_ENV
 
       - name: Set up Go
         if: github.event_name == 'release' || inputs.build_binaries
-        uses: actions/setup-go@v6
+        uses: actions/setup-go@v7
         with:
           go-version: ${{ env.GO_VERSION }}
           cache: true
@@ -55,6 +55,8 @@ jobs:
 
           CGO_ENABLED=0 GOOS=linux   GOARCH=amd64 go build -ldflags "$LDFLAGS" -o ./sarin-linux-amd64 ./cmd/cli/main.go
           CGO_ENABLED=0 GOOS=linux   GOARCH=arm64 go build -ldflags "$LDFLAGS" -o ./sarin-linux-arm64 ./cmd/cli/main.go
+          CGO_ENABLED=0 GOOS=freebsd GOARCH=amd64 go build -ldflags "$LDFLAGS" -o ./sarin-freebsd-amd64 ./cmd/cli/main.go
+          CGO_ENABLED=0 GOOS=freebsd GOARCH=arm64 go build -ldflags "$LDFLAGS" -o ./sarin-freebsd-arm64 ./cmd/cli/main.go
           CGO_ENABLED=0 GOOS=darwin  GOARCH=amd64 go build -ldflags "$LDFLAGS" -o ./sarin-darwin-amd64 ./cmd/cli/main.go
           CGO_ENABLED=0 GOOS=darwin  GOARCH=arm64 go build -ldflags "$LDFLAGS" -o ./sarin-darwin-arm64 ./cmd/cli/main.go
           CGO_ENABLED=0 GOOS=windows GOARCH=amd64 go build -ldflags "$LDFLAGS" -o ./sarin-windows-amd64.exe ./cmd/cli/main.go
@@ -62,29 +64,29 @@ jobs:
 
       - name: Upload Release Assets
         if: github.event_name == 'release' || inputs.build_binaries
-        uses: softprops/action-gh-release@v2
+        uses: softprops/action-gh-release@v3
         with:
           tag_name: ${{ inputs.tag || github.ref_name }}
           files: ./sarin-*
 
       - name: Set up QEMU
         if: github.event_name == 'release' || inputs.build_docker
-        uses: docker/setup-qemu-action@v3
+        uses: docker/setup-qemu-action@v4
 
       - name: Set up Docker Buildx
         if: github.event_name == 'release' || inputs.build_docker
-        uses: docker/setup-buildx-action@v3
+        uses: docker/setup-buildx-action@v4
 
       - name: Login to Docker Hub
         if: github.event_name == 'release' || inputs.build_docker
-        uses: docker/login-action@v3
+        uses: docker/login-action@v4
         with:
           username: ${{ secrets.DOCKERHUB_USERNAME }}
           password: ${{ secrets.DOCKERHUB_TOKEN }}
 
       - name: Build and push Docker image
         if: github.event_name == 'release' || inputs.build_docker
-        uses: docker/build-push-action@v6
+        uses: docker/build-push-action@v7
         with:
           context: .
           platforms: linux/amd64,linux/arm64

.gitignore

@@ -1 +1,5 @@
 bin/*
+
+# Nix build artifacts
+result
+result-*

Dockerfile

@@ -1,4 +1,4 @@
-ARG GO_VERSION=1.26.2
+ARG GO_VERSION=1.26.5
 
 FROM docker.io/library/golang:${GO_VERSION}-alpine AS builder
 

README.md

@@ -3,7 +3,9 @@
 ## Sarin is a high-performance HTTP load testing tool built with Go and fasthttp.
 
 [![Go Reference](https://pkg.go.dev/badge/go.aykhans.me/sarin.svg)](https://pkg.go.dev/go.aykhans.me/sarin)
-[![Go Report Card](https://goreportcard.com/badge/go.aykhans.me/sarin)](https://goreportcard.com/report/go.aykhans.me/sarin)
+[![Docker Pulls](https://img.shields.io/docker/pulls/aykhans/sarin)](https://hub.docker.com/r/aykhans/sarin)
+[![Downloads](https://img.shields.io/github/downloads/aykhans/sarin/total?cacheSeconds=3600)](https://github.com/aykhans/sarin/releases)
+[![Lint](https://img.shields.io/github/actions/workflow/status/aykhans/sarin/lint.yaml?branch=main&label=lint)](https://github.com/aykhans/sarin/actions/workflows/lint.yaml)
 [![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
 
 </div>
@@ -34,10 +36,11 @@ Sarin is designed for efficient HTTP load testing with minimal resource consumpt
 
 ## Installation
 
-### Docker (Recommended)
+<details open>
+<summary><b>Docker</b></summary>
 
 ```sh
-docker pull aykhans/sarin:latest
+docker run -it aykhans/sarin:latest --version
 ```
 
 With a local config file:
@@ -52,11 +55,46 @@ With a remote config file:
 docker run --rm -it aykhans/sarin -f https://example.com/config.yaml
 ```
 
-### Pre-built Binaries
+</details>
+
+<details>
+<summary><b>Nix</b></summary>
+
+Run directly without installing (requires flakes enabled):
+
+```sh
+nix run github:aykhans/sarin -- -U http://example.com -r 100 -c 10
+```
+
+Install into your profile:
+
+```sh
+nix profile install github:aykhans/sarin
+```
+
+Or add it to your own flake via the overlay:
+
+```nix
+{
+  inputs.sarin.url = "github:aykhans/sarin";
+
+  # In your outputs, apply the overlay to nixpkgs:
+  # nixpkgs.overlays = [ inputs.sarin.overlays.default ];
+  # then reference pkgs.sarin
+}
+```
+
+</details>
+
+<details>
+<summary><b>Pre-built Binaries</b></summary>
 
 Download the latest binaries from the [releases](https://github.com/aykhans/sarin/releases) page.
 
-### Building from Source
+</details>
+
+<details>
+<summary><b>Building from Source</b></summary>
 
 Requires [Go 1.26+](https://golang.org/dl/).
 
@@ -72,6 +110,8 @@ CGO_ENABLED=0 go build \
     -o sarin ./cmd/cli/main.go
 ```
 
+</details>
+
 ## Quick Start
 
 Send 10,000 GET requests with 50 concurrent connections and a random User-Agent for each request:

Taskfile.yaml

@@ -3,7 +3,7 @@ version: "3"
 
 vars:
   BIN_DIR: ./bin
-  GOLANGCI_LINT_VERSION: v2.11.4
+  GOLANGCI_LINT_VERSION: v2.12.2
   GOLANGCI: "{{.BIN_DIR}}/golangci-lint-{{.GOLANGCI_LINT_VERSION}}"
 
 tasks:
@@ -74,7 +74,7 @@ tasks:
       - test -f {{.GOLANGCI}}
     cmds:
       - rm -f {{.GOLANGCI}}
-      - curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b {{.BIN_DIR}} {{.GOLANGCI_LINT_VERSION}}
+      - curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/main/install.sh | sh -s -- -b {{.BIN_DIR}} {{.GOLANGCI_LINT_VERSION}}
       - mv {{.BIN_DIR}}/golangci-lint {{.GOLANGCI}}
 
   docker-build:

cmd/cli/main.go

@@ -50,10 +50,10 @@ func main() {
 		ctx,
 		combinedConfig.Methods, combinedConfig.URL, *combinedConfig.Timeout,
 		*combinedConfig.Concurrency, combinedConfig.Requests, combinedConfig.Duration,
-		*combinedConfig.Quiet, *combinedConfig.Insecure, combinedConfig.Params, combinedConfig.Headers,
+		*combinedConfig.Progress == config.ConfigProgressTypeBar, *combinedConfig.Insecure, combinedConfig.Params, combinedConfig.Headers,
 		combinedConfig.Cookies, combinedConfig.Bodies, combinedConfig.Proxies, combinedConfig.Values,
 		*combinedConfig.Output != config.ConfigOutputTypeNone,
-		*combinedConfig.DryRun,
+		*combinedConfig.DryRun, *combinedConfig.LogLevel, *combinedConfig.LogFile,
 		combinedConfig.Lua, combinedConfig.Js,
 	)
 	_ = utilsErr.MustHandle(err,

docs/configuration.md

@@ -26,7 +26,9 @@ Use `-s` or `--show-config` to see the final merged configuration before sending
 | [Concurrency](#concurrency) | `concurrency`<br>(number)           | `-concurrency` / `-c`<br>(number)            | `SARIN_CONCURRENCY`<br>(number)  | `1`     | Number of concurrent workers |
 | [Requests](#requests)       | `requests`<br>(number)              | `-requests` / `-r`<br>(number)               | `SARIN_REQUESTS`<br>(number)     | -       | Total requests to send       |
 | [Duration](#duration)       | `duration`<br>(duration)            | `-duration` / `-d`<br>(duration)             | `SARIN_DURATION`<br>(duration)   | -       | Test duration                |
-| [Quiet](#quiet)             | `quiet`<br>(boolean)                | `-quiet` / `-q`<br>(boolean)                 | `SARIN_QUIET`<br>(boolean)       | `false` | Hide progress bar and logs   |
+| [Log Level](#log-level)     | `logLevel`<br>(string)              | `-log-level` / `-l`<br>(string)              | `SARIN_LOG_LEVEL`<br>(string)    | `error` | Runtime log levels to emit   |
+| [Log File](#log-file)       | `logFile`<br>(string)               | `-log-file` / `-w`<br>(string)               | `SARIN_LOG_FILE`<br>(string)     | -       | Write runtime logs to a file |
+| [Progress](#progress)       | `progress`<br>(string)              | `-progress` / `-p`<br>(string)               | `SARIN_PROGRESS`<br>(string)     | `bar`   | Progress display (bar/none)  |
 | [Output](#output)           | `output`<br>(string)                | `-output` / `-o`<br>(string)                 | `SARIN_OUTPUT`<br>(string)       | `table` | Output format for stats      |
 | [Dry Run](#dry-run)         | `dryRun`<br>(boolean)               | `-dry-run` / `-z`<br>(boolean)               | `SARIN_DRY_RUN`<br>(boolean)     | `false` | Generate without sending     |
 | [Insecure](#insecure)       | `insecure`<br>(boolean)             | `-insecure` / `-I`<br>(boolean)              | `SARIN_INSECURE`<br>(boolean)    | `false` | Skip TLS verification        |
@@ -131,7 +133,7 @@ sarin -U "http://example.com/users/{{ fakeit_UUID }}" -r 1000 -c 10
 
 ## Method
 
-HTTP method(s). If multiple values are provided, Sarin cycles through them in order, starting from a random index for each request. Supports [templating](templating.md).
+HTTP method(s). Defaults to `GET`. If multiple values are provided, Sarin starts at a random index and cycles through them in order. Once the cycle completes, it picks a new random starting point. Supports [templating](templating.md).
 
 **YAML example:**
 
@@ -141,9 +143,9 @@ method: GET
 # OR
 
 method:
-  - GET
+    - GET
-  - POST
+    - POST
-  - PUT
+    - PUT
 ```
 
 **CLI example:**
@@ -160,7 +162,7 @@ SARIN_METHOD=GET
 
 ## Timeout
 
-Request timeout. Must be greater than 0.
+Request timeout. Must be greater than 0. Defaults to `10s`.
 
 Valid time units: `ns`, `us` (or `µs`), `ms`, `s`, `m`, `h`
 
@@ -168,7 +170,7 @@ Valid time units: `ns`, `us` (or `µs`), `ms`, `s`, `m`, `h`
 
 ## Concurrency
 
-Number of concurrent workers. Must be between 1 and 100,000,000.
+Number of concurrent workers. Must be between 1 and 100,000,000. Defaults to `1`.
 
 ## Requests
 
@@ -182,15 +184,34 @@ Valid time units: `ns`, `us` (or `µs`), `ms`, `s`, `m`, `h`
 
 **Examples:** `1m30s`, `25s`, `1h`
 
-## Quiet
+## Log Level
 
-Hide the progress bar and runtime logs.
+Runtime log levels to emit, comma-separated. Valid levels: `info`, `error`. Defaults to `error`.
+
+- `error`: errors that occur while generating or sending a request
+- `info`: every completed response
+
+Leave empty to disable logging entirely.
+
+**Examples:** `error` (only errors), `info` (only responses), `info,error` (both)
+
+## Log File
+
+Write runtime logs to this file instead of the terminal or stderr. The parent directory must exist.
+
+```sh
+sarin -U http://example.com -r 1000 --log-file ./run.log
+```
+
+## Progress
+
+Progress display. Valid values: `bar` (default), `none`. Use `none` to hide the progress bar.
 
 ## Output
 
 Output format for response statistics.
 
-Valid formats: `table`, `json`, `yaml`, `none`
+Valid formats: `table` (default), `json`, `yaml`, `none`
 
 Using `none` disables output and reduces memory usage since response statistics are not stored.
 
@@ -204,7 +225,7 @@ Skip TLS certificate verification.
 
 ## Body
 
-Request body. If multiple values are provided, Sarin cycles through them in order, starting from a random index for each request. Supports [templating](templating.md).
+Request body. If multiple values are provided, Sarin starts at a random index and cycles through them in order. Once the cycle completes, it picks a new random starting point. Supports [templating](templating.md).
 
 **YAML example:**
 
@@ -214,9 +235,9 @@ body: '{"product": "car"}'
 # OR
 
 body:
-  - '{"product": "car"}'
+    - '{"product": "car"}'
-  - '{"product": "phone"}'
+    - '{"product": "phone"}'
-  - '{"product": "watch"}'
+    - '{"product": "watch"}'
 ```
 
 **CLI example:**
@@ -241,19 +262,19 @@ When the same key appears as **separate entries** (in CLI or config file), all v
 
 ```yaml
 params:
-  key1: value1
+    key1: value1
-  key2: [value2, value3]  # cycles between value2 and value3
+    key2: [value2, value3] # cycles between value2 and value3
 
 # OR
 
 params:
-  - key1: value1
+    - key1: value1
-  - key2: [value2, value3]  # cycles between value2 and value3
+    - key2: [value2, value3] # cycles between value2 and value3
 
 # To send both values in every request, use separate entries:
 params:
-  - key2: value2
+    - key2: value2
-  - key2: value3  # both sent in every request
+    - key2: value3 # both sent in every request
 ```
 
 **CLI example:**
@@ -278,19 +299,19 @@ When the same key appears as **separate entries** (in CLI or config file), all v
 
 ```yaml
 headers:
-  key1: value1
+    key1: value1
-  key2: [value2, value3]  # cycles between value2 and value3
+    key2: [value2, value3] # cycles between value2 and value3
 
 # OR
 
 headers:
-  - key1: value1
+    - key1: value1
-  - key2: [value2, value3]  # cycles between value2 and value3
+    - key2: [value2, value3] # cycles between value2 and value3
 
 # To send both values in every request, use separate entries:
 headers:
-  - key2: value2
+    - key2: value2
-  - key2: value3  # both sent in every request
+    - key2: value3 # both sent in every request
 ```
 
 **CLI example:**
@@ -315,19 +336,19 @@ When the same key appears as **separate entries** (in CLI or config file), all v
 
 ```yaml
 cookies:
-  key1: value1
+    key1: value1
-  key2: [value2, value3]  # cycles between value2 and value3
+    key2: [value2, value3] # cycles between value2 and value3
 
 # OR
 
 cookies:
-  - key1: value1
+    - key1: value1
-  - key2: [value2, value3]  # cycles between value2 and value3
+    - key2: [value2, value3] # cycles between value2 and value3
 
 # To send both values in every request, use separate entries:
 cookies:
-  - key2: value2
+    - key2: value2
-  - key2: value3  # both sent in every request
+    - key2: value3 # both sent in every request
 ```
 
 **CLI example:**
@@ -344,7 +365,7 @@ SARIN_COOKIE="key1=value1"
 
 ## Proxy
 
-Proxy URL(s). If multiple values are provided, Sarin cycles through them in order, starting from a random index for each request.
+Proxy URL(s). If multiple values are provided, Sarin starts at a random index and cycles through them in order. Once the cycle completes, it picks a new random starting point.
 
 Supported protocols: `http`, `https`, `socks5`, `socks5h`
 
@@ -356,9 +377,9 @@ proxy: http://proxy1.com
 # OR
 
 proxy:
-  - http://proxy1.com
+    - http://proxy1.com
-  - socks5://proxy2.com
+    - socks5://proxy2.com
-  - socks5h://proxy3.com
+    - socks5h://proxy3.com
 ```
 
 **CLI example:**
@@ -387,9 +408,9 @@ values: "key=value"
 # OR
 
 values: |
-  key1=value1
+    key1=value1
-  key2=value2
+    key2=value2
-  key3=value3
+    key3=value3
 ```
 
 **CLI example:**

docs/examples.md

@@ -13,6 +13,7 @@ This guide provides practical examples for common Sarin use cases.
 - [File Uploads](#file-uploads)
 - [Using Proxies](#using-proxies)
 - [Output Formats](#output-formats)
+- [Runtime Logging](#runtime-logging)
 - [Docker Usage](#docker-usage)
 - [Dry Run Mode](#dry-run-mode)
 - [Show Configuration](#show-configuration)
@@ -719,7 +720,7 @@ proxy: socks5://proxy.example.com:1080
 
 </details>
 
-**Multiple proxies (load balanced):**
+**Multiple proxies (randomly cycled):**
 
 ```sh
 sarin -U http://example.com -r 1000 -c 10 \
@@ -836,10 +837,10 @@ output: none
 
 </details>
 
-**Quiet mode (hide progress bar):**
+**Hide the progress bar:**
 
 ```sh
-sarin -U http://example.com -r 1000 -c 10 -q
+sarin -U http://example.com -r 1000 -c 10 -p none
 ```
 
 <details>
@@ -849,7 +850,42 @@ sarin -U http://example.com -r 1000 -c 10 -q
 url: http://example.com
 requests: 1000
 concurrency: 10
-quiet: true
+progress: none
+```
+
+</details>
+
+## Runtime Logging
+
+`--log-level` selects which runtime logs Sarin emits (comma-separated `info` and `error`, default `error`). `error` covers request and generation errors, `info` covers every completed response (status, duration, headers, body). Logs appear in the progress log box on an interactive terminal, go to stderr when piped, or go to a file with `--log-file`.
+
+**Log responses and errors:**
+
+```sh
+sarin -U http://example.com -r 1000 -c 10 -l info,error
+```
+
+**Write logs to a file (the progress bar stays on screen):**
+
+```sh
+sarin -U http://example.com -r 1000 -c 10 -l info --log-file ./run.log
+```
+
+**Capture logs while keeping results on stdout:**
+
+```sh
+sarin -U http://example.com -r 1000 -l info -o json > stats.json 2> run.log
+```
+
+<details>
+<summary>YAML equivalent</summary>
+
+```yaml
+url: http://example.com
+requests: 1000
+concurrency: 10
+logLevel: info,error
+logFile: ./run.log
 ```
 
 </details>

docs/templating.md

@@ -183,19 +183,19 @@ body: '{{ body_FormData "image" "@https://example.com/photo.jpg" }}'
 
 # Mixed text fields and files
 body: |
-  {{ body_FormData
+    {{ body_FormData
-     "title" "My Report"
+       "title" "My Report"
-     "author" "John Doe"
+       "author" "John Doe"
-     "cover" "@/path/to/cover.jpg"
+       "cover" "@/path/to/cover.jpg"
-     "document" "@/path/to/report.pdf"
+       "document" "@/path/to/report.pdf"
-  }}
+    }}
 
 # Multiple files with same field name
 body: |
-  {{ body_FormData
+    {{ body_FormData
-     "files" "@/path/to/file1.pdf"
+       "files" "@/path/to/file1.pdf"
-     "files" "@/path/to/file2.pdf"
+       "files" "@/path/to/file2.pdf"
-  }}
+    }}
 
 # Escape @ for literal value (sends "@username")
 body: '{{ body_FormData "twitter" "@@username" }}'
@@ -226,7 +226,7 @@ body: '{"file": "{{ file_Base64 "/path/to/document.pdf" }}", "filename": "docume
 body: '{"image": "{{ file_Base64 "https://example.com/photo.jpg" }}"}'
 
 # Combined with values for reuse
-values: "FILE_DATA={{ file_Base64 \"/path/to/file.bin\" }}"
+values: 'FILE_DATA={{ file_Base64 "/path/to/file.bin" }}'
 body: '{"data": "{{ .Values.FILE_DATA }}"}'
 ```
 
@@ -234,7 +234,7 @@ body: '{"data": "{{ .Values.FILE_DATA }}"}'
 
 Captcha functions solve a captcha challenge through a third-party solving service and return the resulting token, which can then be embedded directly into a request. They are intended for load testing endpoints protected by reCAPTCHA, hCaptcha, or Cloudflare Turnstile.
 
-The functions are organized by service: `twocaptcha_*`, `anticaptcha_*`, and `capsolver_*`. Each accepts the API key as the first argument so no global configuration is required — bring your own key and use any of the supported services per template.
+The functions are organized by service: `twocaptcha_*`, `anticaptcha_*`, and `capsolver_*`. Each accepts the API key as the first argument so no global configuration is required. Bring your own key and use any of the supported services per template.
 
 > **Important: performance and cost:**
 >

flake.lock

@@ -0,0 +1,27 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1784796856,
+        "narHash": "sha256-wWFrV5/Qbm+lyt5x20E/bSbfJiGKMo4RCxZV8cl/WZI=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "e2587caef70cea85dd97d7daab492899902dbf5d",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,55 @@
+{
+  description = "Sarin - high-performance HTTP load testing tool built with Go and fasthttp";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+  };
+
+  outputs = { self, nixpkgs }:
+    let
+      inherit (nixpkgs) lib;
+
+      systems = [
+        "x86_64-linux"
+        "aarch64-linux"
+        "x86_64-darwin"
+        "aarch64-darwin"
+      ];
+
+      forAllSystems = f: lib.genAttrs systems (system: f nixpkgs.legacyPackages.${system});
+
+      rev = self.rev or self.dirtyRev or "unknown";
+
+      # self.lastModifiedDate is "YYYYMMDDHHMMSS"; reshape to RFC 3339 (UTC).
+      raw = self.lastModifiedDate or "19700101000000";
+      s = i: n: lib.substring i n raw;
+      buildDate = "${s 0 4}-${s 4 2}-${s 6 2}T${s 8 2}:${s 10 2}:${s 12 2}Z";
+    in
+    {
+      packages = forAllSystems (pkgs: {
+        default = pkgs.callPackage ./nix/package.nix {
+          inherit rev buildDate;
+        };
+      });
+
+      # nix run github:aykhans/sarin -- <args>
+      apps = forAllSystems (pkgs: {
+        default = {
+          type = "app";
+          program = "${self.packages.${pkgs.system}.default}/bin/sarin";
+          meta.description = "High-performance HTTP load testing tool";
+        };
+      });
+
+      devShells = forAllSystems (pkgs: {
+        default = pkgs.mkShell {
+          packages = [ pkgs.go_1_26 pkgs.golangci-lint pkgs.go-task ];
+        };
+      });
+
+      # For downstream flakes: inputs.sarin.overlays.default
+      overlays.default = final: _prev: {
+        sarin = final.callPackage ./nix/package.nix { };
+      };
+    };
+}

go.mod

@@ -1,46 +1,46 @@
 module go.aykhans.me/sarin
 
-go 1.26.2
+go 1.26.5
 
 require (
-	github.com/brianvoe/gofakeit/v7 v7.14.1
+	github.com/brianvoe/gofakeit/v7 v7.15.0
 	github.com/charmbracelet/bubbles v1.0.0
 	github.com/charmbracelet/bubbletea v1.3.10
 	github.com/charmbracelet/glamour v1.0.0
 	github.com/charmbracelet/lipgloss v1.1.1-0.20250404203927-76690c660834
 	github.com/charmbracelet/x/term v0.2.2
-	github.com/dop251/goja v0.0.0-20260311135729-065cd970411c
+	github.com/dop251/goja v0.0.0-20260723142020-b4aef50fa347
 	github.com/joho/godotenv v1.5.1
-	github.com/valyala/fasthttp v1.70.0
+	github.com/valyala/fasthttp v1.72.0
 	github.com/yuin/gopher-lua v1.1.2
 	go.aykhans.me/utils v1.0.7
-	go.yaml.in/yaml/v4 v4.0.0-rc.4
+	go.yaml.in/yaml/v4 v4.0.0-rc.6
-	golang.org/x/net v0.53.0
+	golang.org/x/net v0.57.0
 )
 
 require (
-	github.com/alecthomas/chroma/v2 v2.23.1 // indirect
+	github.com/alecthomas/chroma/v2 v2.27.0 // indirect
-	github.com/andybalholm/brotli v1.2.1 // indirect
+	github.com/andybalholm/brotli v1.2.2 // indirect
 	github.com/aymanbagabas/go-osc52/v2 v2.0.1 // indirect
 	github.com/aymerick/douceur v0.2.0 // indirect
 	github.com/charmbracelet/colorprofile v0.4.3 // indirect
 	github.com/charmbracelet/harmonica v0.2.0 // indirect
-	github.com/charmbracelet/x/ansi v0.11.6 // indirect
+	github.com/charmbracelet/x/ansi v0.11.7 // indirect
 	github.com/charmbracelet/x/cellbuf v0.0.15 // indirect
-	github.com/charmbracelet/x/exp/slice v0.0.0-20260329003944-7eda8903d971 // indirect
+	github.com/charmbracelet/x/exp/slice v0.0.0-20260726004341-482a56510f1b // indirect
 	github.com/clipperhouse/displaywidth v0.11.0 // indirect
 	github.com/clipperhouse/uax29/v2 v2.7.0 // indirect
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
-	github.com/dlclark/regexp2 v1.11.5 // indirect
+	github.com/dlclark/regexp2/v2 v2.5.2 // indirect
 	github.com/erikgeiser/coninput v0.0.0-20211004153227-1c3628e74d0f // indirect
 	github.com/go-sourcemap/sourcemap v2.1.4+incompatible // indirect
-	github.com/google/pprof v0.0.0-20260302011040-a15ffb7f9dcc // indirect
+	github.com/google/pprof v0.0.0-20260709232956-b9395ee17fa0 // indirect
 	github.com/gorilla/css v1.0.1 // indirect
-	github.com/klauspost/compress v1.18.5 // indirect
+	github.com/klauspost/compress v1.19.1 // indirect
 	github.com/lucasb-eyer/go-colorful v1.4.0 // indirect
-	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/mattn/go-isatty v0.0.24 // indirect
 	github.com/mattn/go-localereader v0.0.1 // indirect
-	github.com/mattn/go-runewidth v0.0.21 // indirect
+	github.com/mattn/go-runewidth v0.0.27 // indirect
 	github.com/microcosm-cc/bluemonday v1.0.27 // indirect
 	github.com/muesli/ansi v0.0.0-20230316100256-276c6243b2f6 // indirect
 	github.com/muesli/cancelreader v0.2.2 // indirect
@@ -50,9 +50,9 @@ require (
 	github.com/rivo/uniseg v0.4.7 // indirect
 	github.com/valyala/bytebufferpool v1.0.0 // indirect
 	github.com/xo/terminfo v0.0.0-20220910002029-abceb7e1c41e // indirect
-	github.com/yuin/goldmark v1.8.2 // indirect
+	github.com/yuin/goldmark v1.8.4 // indirect
 	github.com/yuin/goldmark-emoji v1.0.6 // indirect
-	golang.org/x/sys v0.43.0 // indirect
+	golang.org/x/sys v0.47.0 // indirect
-	golang.org/x/term v0.42.0 // indirect
+	golang.org/x/term v0.45.0 // indirect
-	golang.org/x/text v0.36.0 // indirect
+	golang.org/x/text v0.40.0 // indirect
 )

go.sum

@@ -1,21 +1,21 @@
-github.com/Masterminds/semver/v3 v3.2.1 h1:RN9w6+7QoMeJVGyfmbcgs28Br8cvmnucEXnY0rYXWg0=
+github.com/Masterminds/semver/v3 v3.5.0 h1:kQceYJfbupGfZOKZQg0kou0DgAKhzDg2NZPAwZ/2OOE=
-github.com/Masterminds/semver/v3 v3.2.1/go.mod h1:qvl/7zhW3nngYb5+80sSMF+FG2BjYrf8m9wsX0PNOMQ=
+github.com/Masterminds/semver/v3 v3.5.0/go.mod h1:4V+yj/TJE1HU9XfppCwVMZq3I84lprf4nC11bSS5beM=
 github.com/alecthomas/assert/v2 v2.11.0 h1:2Q9r3ki8+JYXvGsDyBXwH3LcJ+WK5D0gc5E8vS6K3D0=
 github.com/alecthomas/assert/v2 v2.11.0/go.mod h1:Bze95FyfUr7x34QZrjL+XP+0qgp/zg8yS+TtBj1WA3k=
-github.com/alecthomas/chroma/v2 v2.23.1 h1:nv2AVZdTyClGbVQkIzlDm/rnhk1E9bU9nXwmZ/Vk/iY=
+github.com/alecthomas/chroma/v2 v2.27.0 h1:FodwmyOBgJULFYmDqibcp9pvfDLWdtPRh9v/r5BXYZs=
-github.com/alecthomas/chroma/v2 v2.23.1/go.mod h1:NqVhfBR0lte5Ouh3DcthuUCTUpDC9cxBOfyMbMQPs3o=
+github.com/alecthomas/chroma/v2 v2.27.0/go.mod h1:NjJ3ciIgrqBNeIkWZ4e46nseoLDslxU1LmfCoL+wcY8=
 github.com/alecthomas/repr v0.5.2 h1:SU73FTI9D1P5UNtvseffFSGmdNci/O6RsqzeXJtP0Qs=
 github.com/alecthomas/repr v0.5.2/go.mod h1:Fr0507jx4eOXV7AlPV6AVZLYrLIuIeSOWtW57eE/O/4=
-github.com/andybalholm/brotli v1.2.1 h1:R+f5xP285VArJDRgowrfb9DqL18yVK0gKAW/F+eTWro=
+github.com/andybalholm/brotli v1.2.2 h1:HzTuoo2ErYQqf5qvcJInB8uvqSVxRttzkFexPWtnceM=
-github.com/andybalholm/brotli v1.2.1/go.mod h1:rzTDkvFWvIrjDXZHkuS16NPggd91W3kUSvPlQ1pLaKY=
+github.com/andybalholm/brotli v1.2.2/go.mod h1:rzTDkvFWvIrjDXZHkuS16NPggd91W3kUSvPlQ1pLaKY=
 github.com/aymanbagabas/go-osc52/v2 v2.0.1 h1:HwpRHbFMcZLEVr42D4p7XBqjyuxQH5SMiErDT4WkJ2k=
 github.com/aymanbagabas/go-osc52/v2 v2.0.1/go.mod h1:uYgXzlJ7ZpABp8OJ+exZzJJhRNQ2ASbcXHWsFqH8hp8=
 github.com/aymanbagabas/go-udiff v0.3.1 h1:LV+qyBQ2pqe0u42ZsUEtPiCaUoqgA9gYRDs3vj1nolY=
 github.com/aymanbagabas/go-udiff v0.3.1/go.mod h1:G0fsKmG+P6ylD0r6N/KgQD/nWzgfnl8ZBcNLgcbrw8E=
 github.com/aymerick/douceur v0.2.0 h1:Mv+mAeH1Q+n9Fr+oyamOlAkUNPWPlA8PPGR0QAaYuPk=
 github.com/aymerick/douceur v0.2.0/go.mod h1:wlT5vV2O3h55X9m7iVYN0TBM0NH/MmbLnd30/FjWUq4=
-github.com/brianvoe/gofakeit/v7 v7.14.1 h1:a7fe3fonbj0cW3wgl5VwIKfZtiH9C3cLnwcIXWT7sow=
+github.com/brianvoe/gofakeit/v7 v7.15.0 h1:kGLYAWN8tnmxq2PelKVK6zwpM7kMxdz9SGPH31mFkNs=
-github.com/brianvoe/gofakeit/v7 v7.14.1/go.mod h1:QXuPeBw164PJCzCUZVmgpgHJ3Llj49jSLVkKPMtxtxA=
+github.com/brianvoe/gofakeit/v7 v7.15.0/go.mod h1:QXuPeBw164PJCzCUZVmgpgHJ3Llj49jSLVkKPMtxtxA=
 github.com/charmbracelet/bubbles v1.0.0 h1:12J8/ak/uCZEMQ6KU7pcfwceyjLlWsDLAxB5fXonfvc=
 github.com/charmbracelet/bubbles v1.0.0/go.mod h1:9d/Zd5GdnauMI5ivUIVisuEm3ave1XwXtD1ckyV6r3E=
 github.com/charmbracelet/bubbletea v1.3.10 h1:otUDHWMMzQSB0Pkc87rm691KZ3SWa4KUlvF9nRvCICw=
@@ -28,14 +28,14 @@ github.com/charmbracelet/harmonica v0.2.0 h1:8NxJWRWg/bzKqqEaaeFNipOu77YR5t8aSwG
 github.com/charmbracelet/harmonica v0.2.0/go.mod h1:KSri/1RMQOZLbw7AHqgcBycp8pgJnQMYYT8QZRqZ1Ao=
 github.com/charmbracelet/lipgloss v1.1.1-0.20250404203927-76690c660834 h1:ZR7e0ro+SZZiIZD7msJyA+NjkCNNavuiPBLgerbOziE=
 github.com/charmbracelet/lipgloss v1.1.1-0.20250404203927-76690c660834/go.mod h1:aKC/t2arECF6rNOnaKaVU6y4t4ZeHQzqfxedE/VkVhA=
-github.com/charmbracelet/x/ansi v0.11.6 h1:GhV21SiDz/45W9AnV2R61xZMRri5NlLnl6CVF7ihZW8=
+github.com/charmbracelet/x/ansi v0.11.7 h1:kzv1kJvjg2S3r9KHo8hDdHFQLEqn4RBCb39dAYC84jI=
-github.com/charmbracelet/x/ansi v0.11.6/go.mod h1:2JNYLgQUsyqaiLovhU2Rv/pb8r6ydXKS3NIttu3VGZQ=
+github.com/charmbracelet/x/ansi v0.11.7/go.mod h1:9qGpnAVYz+8ACONkZBUWPtL7lulP9No6p1epAihUZwQ=
 github.com/charmbracelet/x/cellbuf v0.0.15 h1:ur3pZy0o6z/R7EylET877CBxaiE1Sp1GMxoFPAIztPI=
 github.com/charmbracelet/x/cellbuf v0.0.15/go.mod h1:J1YVbR7MUuEGIFPCaaZ96KDl5NoS0DAWkskup+mOY+Q=
 github.com/charmbracelet/x/exp/golden v0.0.0-20241011142426-46044092ad91 h1:payRxjMjKgx2PaCWLZ4p3ro9y97+TVLZNaRZgJwSVDQ=
 github.com/charmbracelet/x/exp/golden v0.0.0-20241011142426-46044092ad91/go.mod h1:wDlXFlCrmJ8J+swcL/MnGUuYnqgQdW9rhSD61oNMb6U=
-github.com/charmbracelet/x/exp/slice v0.0.0-20260329003944-7eda8903d971 h1:wae/9jUCdhUiuyCcOzZZ+vJEB7uJx+IvtTnpCqcW1ZQ=
+github.com/charmbracelet/x/exp/slice v0.0.0-20260726004341-482a56510f1b h1:VKASlRztdxT172siF4nJCwD1C+3mbveX41BiA96fIpA=
-github.com/charmbracelet/x/exp/slice v0.0.0-20260329003944-7eda8903d971/go.mod h1:vqEfX6xzqW1pKKZUUiFOKg0OQ7bCh54Q2vR/tserrRA=
+github.com/charmbracelet/x/exp/slice v0.0.0-20260726004341-482a56510f1b/go.mod h1:vqEfX6xzqW1pKKZUUiFOKg0OQ7bCh54Q2vR/tserrRA=
 github.com/charmbracelet/x/term v0.2.2 h1:xVRT/S2ZcKdhhOuSP4t5cLi5o+JxklsoEObBSgfgZRk=
 github.com/charmbracelet/x/term v0.2.2/go.mod h1:kF8CY5RddLWrsgVwpw4kAa6TESp6EB5y3uxGLeCqzAI=
 github.com/clipperhouse/displaywidth v0.11.0 h1:lBc6kY44VFw+TDx4I8opi/EtL9m20WSEFgwIwO+UVM8=
@@ -44,33 +44,35 @@ github.com/clipperhouse/uax29/v2 v2.7.0 h1:+gs4oBZ2gPfVrKPthwbMzWZDaAFPGYK72F0NJ
 github.com/clipperhouse/uax29/v2 v2.7.0/go.mod h1:EFJ2TJMRUaplDxHKj1qAEhCtQPW2tJSwu5BF98AuoVM=
 github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc h1:U9qPSI2PIWSS1VwoXQT9A3Wy9MM3WgvqSxFWenqJduM=
 github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/dlclark/regexp2 v1.11.5 h1:Q/sSnsKerHeCkc/jSTNq1oCm7KiVgUMZRDUoRu0JQZQ=
+github.com/dlclark/regexp2/v2 v2.5.2 h1:HAsucWRhsqcDzl6Ua9aR8JwYOTzrZyPrF0/FNxJVAI0=
-github.com/dlclark/regexp2 v1.11.5/go.mod h1:DHkYz0B9wPfa6wondMfaivmHpzrQ3v9q8cnmRbL6yW8=
+github.com/dlclark/regexp2/v2 v2.5.2/go.mod h1:avUrQvPaLz2DrFNHJF0taWAFFX2C1GMSSoeiqFjcBmU=
-github.com/dop251/goja v0.0.0-20260311135729-065cd970411c h1:OcLmPfx1T1RmZVHHFwWMPaZDdRf0DBMZOFMVWJa7Pdk=
+github.com/dop251/goja v0.0.0-20260723142020-b4aef50fa347 h1:RZr+96+PKQjn444QL1K9MtncwJ/PwfE+3TJLCYJL8es=
-github.com/dop251/goja v0.0.0-20260311135729-065cd970411c/go.mod h1:MxLav0peU43GgvwVgNbLAj1s/bSGboKkhuULvq/7hx4=
+github.com/dop251/goja v0.0.0-20260723142020-b4aef50fa347/go.mod h1:LiIEzozrcvNXorsG/3+ypGqdTUAqZryhzSsqi0oU/Qg=
 github.com/erikgeiser/coninput v0.0.0-20211004153227-1c3628e74d0f h1:Y/CXytFA4m6baUTXGLOoWe4PQhGxaX0KpnayAqC48p4=
 github.com/erikgeiser/coninput v0.0.0-20211004153227-1c3628e74d0f/go.mod h1:vw97MGsxSvLiUE2X8qFplwetxpGLQrlU1Q9AUEIzCaM=
 github.com/go-sourcemap/sourcemap v2.1.4+incompatible h1:a+iTbH5auLKxaNwQFg0B+TCYl6lbukKPc7b5x0n1s6Q=
 github.com/go-sourcemap/sourcemap v2.1.4+incompatible/go.mod h1:F8jJfvm2KbVjc5NqelyYJmf/v5J0dwNLS2mL4sNA1Jg=
-github.com/google/pprof v0.0.0-20260302011040-a15ffb7f9dcc h1:VBbFa1lDYWEeV5FZKUiYKYT0VxCp9twUmmaq9eb8sXw=
+github.com/goccy/go-yaml v1.19.2 h1:PmFC1S6h8ljIz6gMRBopkjP1TVT7xuwrButHID66PoM=
-github.com/google/pprof v0.0.0-20260302011040-a15ffb7f9dcc/go.mod h1:MxpfABSjhmINe3F1It9d+8exIHFvUqtLIRCdOGNXqiI=
+github.com/goccy/go-yaml v1.19.2/go.mod h1:XBurs7gK8ATbW4ZPGKgcbrY1Br56PdM69F7LkFRi1kA=
+github.com/google/pprof v0.0.0-20260709232956-b9395ee17fa0 h1:du0WGc8xSKq/++e0cglxhS/mXVqsR7+c7jLEi5Vqduw=
+github.com/google/pprof v0.0.0-20260709232956-b9395ee17fa0/go.mod h1:MxpfABSjhmINe3F1It9d+8exIHFvUqtLIRCdOGNXqiI=
 github.com/gorilla/css v1.0.1 h1:ntNaBIghp6JmvWnxbZKANoLyuXTPZ4cAMlo6RyhlbO8=
 github.com/gorilla/css v1.0.1/go.mod h1:BvnYkspnSzMmwRK+b8/xgNPLiIuNZr6vbZBTPQ2A3b0=
 github.com/hexops/gotextdiff v1.0.3 h1:gitA9+qJrrTCsiCl7+kh75nPqQt1cx4ZkudSTLoUqJM=
 github.com/hexops/gotextdiff v1.0.3/go.mod h1:pSWU5MAI3yDq+fZBTazCSJysOMbxWL1BSow5/V2vxeg=
 github.com/joho/godotenv v1.5.1 h1:7eLL/+HRGLY0ldzfGMeQkb7vMd0as4CfYvUVzLqw0N0=
 github.com/joho/godotenv v1.5.1/go.mod h1:f4LDr5Voq0i2e/R5DDNOoa2zzDfwtkZa6DnEwAbqwq4=
-github.com/klauspost/compress v1.18.5 h1:/h1gH5Ce+VWNLSWqPzOVn6XBO+vJbCNGvjoaGBFW2IE=
+github.com/klauspost/compress v1.19.1 h1:VsB4HPswih7mmZ8WleSFQ75c/Ui1M4trX5oAsJnhSlk=
-github.com/klauspost/compress v1.18.5/go.mod h1:cwPg85FWrGar70rWktvGQj8/hthj3wpl0PGDogxkrSQ=
+github.com/klauspost/compress v1.19.1/go.mod h1:cwPg85FWrGar70rWktvGQj8/hthj3wpl0PGDogxkrSQ=
 github.com/lucasb-eyer/go-colorful v1.4.0 h1:UtrWVfLdarDgc44HcS7pYloGHJUjHV/4FwW4TvVgFr4=
 github.com/lucasb-eyer/go-colorful v1.4.0/go.mod h1:R4dSotOR9KMtayYi1e77YzuveK+i7ruzyGqttikkLy0=
-github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
+github.com/mattn/go-isatty v0.0.24 h1:tGZZoVgT/KiqK1c8ocVLeDS8BSWMRd47J3Lbz7vsReI=
-github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
+github.com/mattn/go-isatty v0.0.24/go.mod h1:nMCL3Zebbrt45jsMDgnfIwz6ydEQApk5oEI3HqDio6A=
 github.com/mattn/go-localereader v0.0.1 h1:ygSAOl7ZXTx4RdPYinUpg6W99U8jWvWi9Ye2JC/oIi4=
 github.com/mattn/go-localereader v0.0.1/go.mod h1:8fBrzywKY7BI3czFoHkuzRoWE9C+EiG4R1k4Cjx5p88=
 github.com/mattn/go-runewidth v0.0.12/go.mod h1:RAqKPSqVFrSLVXbA8x7dzmKdmGzieGRCM46jaSJTDAk=
-github.com/mattn/go-runewidth v0.0.21 h1:jJKAZiQH+2mIinzCJIaIG9Be1+0NR+5sz/lYEEjdM8w=
+github.com/mattn/go-runewidth v0.0.27 h1:Feg/Oou5zI/wnpgDF6omIU0OokC9GxLC/WRknhVlIR0=
-github.com/mattn/go-runewidth v0.0.21/go.mod h1:XBkDxAl56ILZc9knddidhrOlY5R/pDhgLpndooCuJAs=
+github.com/mattn/go-runewidth v0.0.27/go.mod h1:3qAiGCV4Koz/yuveO58qUefmUTRm8r0IGEXZ9jeHp/8=
 github.com/microcosm-cc/bluemonday v1.0.27 h1:MpEUotklkwCSLeH+Qdx1VJgNqLlpY2KXwXFM08ygZfk=
 github.com/microcosm-cc/bluemonday v1.0.27/go.mod h1:jFi9vgW+H7c3V0lb6nR74Ib/DIB5OBs92Dimizgw2cA=
 github.com/muesli/ansi v0.0.0-20230316100256-276c6243b2f6 h1:ZK8zHtRHOkbHy6Mmr5D264iyp3TiX5OmNcI5cIARiQI=
@@ -91,35 +93,32 @@ github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu
 github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
 github.com/valyala/bytebufferpool v1.0.0 h1:GqA5TC/0021Y/b9FG4Oi9Mr3q7XYx6KllzawFIhcdPw=
 github.com/valyala/bytebufferpool v1.0.0/go.mod h1:6bBcMArwyJ5K/AmCkWv1jt77kVWyCJ6HpOuEn7z0Csc=
-github.com/valyala/fasthttp v1.70.0 h1:LAhMGcWk13QZWm85+eg8ZBNbrq5mnkWFGbHMUJHIdXA=
+github.com/valyala/fasthttp v1.72.0 h1:R7kYdoWhn1ye1fVpP+cDHDJwYm3NkwLliwgzJ/Abg7M=
-github.com/valyala/fasthttp v1.70.0/go.mod h1:oDZEHHkJ/Buyklg6uURmYs19442zFSnCIfX3j1FY3pE=
+github.com/valyala/fasthttp v1.72.0/go.mod h1:zsbLTYqcpIktdQytlVBwIjY9La5d6bs990nBxWg8efk=
 github.com/xo/terminfo v0.0.0-20220910002029-abceb7e1c41e h1:JVG44RsyaB9T2KIHavMF/ppJZNG9ZpyihvCd0w101no=
 github.com/xo/terminfo v0.0.0-20220910002029-abceb7e1c41e/go.mod h1:RbqR21r5mrJuqunuUZ/Dhy/avygyECGrLceyNeo4LiM=
 github.com/xyproto/randomstring v1.0.5 h1:YtlWPoRdgMu3NZtP45drfy1GKoojuR7hmRcnhZqKjWU=
 github.com/xyproto/randomstring v1.0.5/go.mod h1:rgmS5DeNXLivK7YprL0pY+lTuhNQW3iGxZ18UQApw/E=
-github.com/yuin/goldmark v1.8.2 h1:kEGpgqJXdgbkhcOgBxkC0X0PmoPG1ZyoZ117rDVp4zE=
+github.com/yuin/goldmark v1.8.4 h1:oat/nd3U6NeQqFEL3xpEJq7d7c86NI+DbSNGAs4xnjA=
-github.com/yuin/goldmark v1.8.2/go.mod h1:ip/1k0VRfGynBgxOz0yCqHrbZXhcjxyuS66Brc7iBKg=
+github.com/yuin/goldmark v1.8.4/go.mod h1:ip/1k0VRfGynBgxOz0yCqHrbZXhcjxyuS66Brc7iBKg=
 github.com/yuin/goldmark-emoji v1.0.6 h1:QWfF2FYaXwL74tfGOW5izeiZepUDroDJfWubQI9HTHs=
 github.com/yuin/goldmark-emoji v1.0.6/go.mod h1:ukxJDKFpdFb5x0a5HqbdlcKtebh086iJpI31LTKmWuA=
 github.com/yuin/gopher-lua v1.1.2 h1:yF/FjE3hD65tBbt0VXLE13HWS9h34fdzJmrWRXwobGA=
 github.com/yuin/gopher-lua v1.1.2/go.mod h1:7aRmXIWl37SqRf0koeyylBEzJ+aPt8A+mmkQ4f1ntR8=
 go.aykhans.me/utils v1.0.7 h1:ClHXHlWmkjfFlD7+w5BQY29lKCEztxY/yCf543x4hZw=
 go.aykhans.me/utils v1.0.7/go.mod h1:0Jz8GlZLN35cCHLOLx39sazWwEe33bF6SYlSeqzEXoI=
-go.yaml.in/yaml/v4 v4.0.0-rc.4 h1:UP4+v6fFrBIb1l934bDl//mmnoIZEDK0idg1+AIvX5U=
+go.yaml.in/yaml/v4 v4.0.0-rc.6 h1:1h7H1ohdUh93/FyE4YaDa1Zh64K6VVbjF4K6WUxMtH4=
-go.yaml.in/yaml/v4 v4.0.0-rc.4/go.mod h1:aZqd9kCMsGL7AuUv/m/PvWLdg5sjJsZ4oHDEnfPPfY0=
+go.yaml.in/yaml/v4 v4.0.0-rc.6/go.mod h1:aZqd9kCMsGL7AuUv/m/PvWLdg5sjJsZ4oHDEnfPPfY0=
 golang.org/x/exp v0.0.0-20231006140011-7918f672742d h1:jtJma62tbqLibJ5sFQz8bKtEM8rJBtfilJ2qTU199MI=
 golang.org/x/exp v0.0.0-20231006140011-7918f672742d/go.mod h1:ldy0pHrwJyGW56pPQzzkH36rKxoZW1tw7ZJpeKx+hdo=
-golang.org/x/net v0.53.0 h1:d+qAbo5L0orcWAr0a9JweQpjXF19LMXJE8Ey7hwOdUA=
+golang.org/x/net v0.57.0 h1:K5+3DljvIuDG9/Jv9rvyMywYNFCQ9RSUY6OOTTkT+tE=
-golang.org/x/net v0.53.0/go.mod h1:JvMuJH7rrdiCfbeHoo3fCQU24Lf5JJwT9W3sJFulfgs=
+golang.org/x/net v0.57.0/go.mod h1:KpXc8iv+r3XplLAG/f7Jsf9RPszJzdR0f58q9vGOuEU=
 golang.org/x/sys v0.0.0-20210809222454-d867a43fc93e/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.47.0 h1:o7XGOvZQCADBQQ4Y7VNq2dRWQR7JmOUW8Kxx4ZsNgWs=
-golang.org/x/sys v0.43.0 h1:Rlag2XtaFTxp19wS8MXlJwTvoh8ArU6ezoyFsMyCTNI=
+golang.org/x/sys v0.47.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
-golang.org/x/sys v0.43.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
+golang.org/x/term v0.45.0 h1:NwWyBmoJCbfTHpxrWoZ9C6/VxOf7ic219I8xZZFdrf0=
-golang.org/x/term v0.42.0 h1:UiKe+zDFmJobeJ5ggPwOshJIVt6/Ft0rcfrXZDLWAWY=
+golang.org/x/term v0.45.0/go.mod h1:9aqxs0blBcrm/n0L9QW0aRVD+ktan8ssZromtqJC43w=
-golang.org/x/term v0.42.0/go.mod h1:Dq/D+snpsbazcBG5+F9Q1n2rXV8Ma+71xEjTRufARgY=
+golang.org/x/text v0.40.0 h1:Ub2Z6/xjgF1WrYQz2nuITOEegKFtiIy+rieRJ5lHZKs=
-golang.org/x/text v0.36.0 h1:JfKh3XmcRPqZPKevfXVpI1wXPTqbkE5f7JA92a55Yxg=
+golang.org/x/text v0.40.0/go.mod h1:hpnzDAfGV753zIKo+wk3u1bVKCGPbrnF7+7LBF/UHVY=
-golang.org/x/text v0.36.0/go.mod h1:NIdBknypM8iqVmPiuco0Dh6P5Jcdk8lJL0CUebqK164=
-gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
-gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

internal/config/cli.go

@@ -27,7 +27,9 @@ Flags:
     -c, -concurrency   uint       Number of concurrent requests (default %d)
     -r, -requests      uint       Number of total requests
     -d, -duration      time       Maximum duration for the test (e.g. 30s, 1m, 5h)
-    -q, -quiet         bool       Hide the progress bar and runtime logs (default %v)
+    -l, -log-level     string     Runtime log levels to emit, comma-separated (possible values: info, error) (default %s)
+    -w, -log-file      string     Write runtime logs to this file instead of the terminal/stderr
+    -p, -progress      string     Progress display (possible values: bar, none) (default '%v')
     -o, -output        string     Output format (possible values: table, json, yaml, none) (default '%v')
     -z, -dry-run       bool       Run without sending requests (default %v)
 
@@ -88,7 +90,9 @@ func (parser ConfigCLIParser) Parse() (*Config, error) {
 		concurrency  uint
 		requestCount uint64
 		duration     time.Duration
-		quiet        bool
+		logLevel     string
+		logFile      string
+		progress     string
 		output       string
 		dryRun       bool
 
@@ -127,8 +131,14 @@ func (parser ConfigCLIParser) Parse() (*Config, error) {
 		flagSet.DurationVar(&duration, "duration", 0, "Maximum duration for the test")
 		flagSet.DurationVar(&duration, "d", 0, "Maximum duration for the test")
 
-		flagSet.BoolVar(&quiet, "quiet", false, "Hide the progress bar and runtime logs")
+		flagSet.StringVar(&logLevel, "log-level", "", "Runtime log levels to emit, comma-separated (possible values: info, error)")
-		flagSet.BoolVar(&quiet, "q", false, "Hide the progress bar and runtime logs")
+		flagSet.StringVar(&logLevel, "l", "", "Runtime log levels to emit, comma-separated (possible values: info, error)")
+
+		flagSet.StringVar(&logFile, "log-file", "", "Write runtime logs to this file instead of the terminal/stderr")
+		flagSet.StringVar(&logFile, "w", "", "Write runtime logs to this file instead of the terminal/stderr")
+
+		flagSet.StringVar(&progress, "progress", "", "Progress display (possible values: bar, none)")
+		flagSet.StringVar(&progress, "p", "", "Progress display (possible values: bar, none)")
 
 		flagSet.StringVar(&output, "output", "", "Output format (possible values: table, json, yaml, none)")
 		flagSet.StringVar(&output, "o", "", "Output format (possible values: table, json, yaml, none)")
@@ -205,8 +215,12 @@ func (parser ConfigCLIParser) Parse() (*Config, error) {
 			config.Requests = new(requestCount)
 		case "duration", "d":
 			config.Duration = new(duration)
-		case "quiet", "q":
+		case "log-level", "l":
-			config.Quiet = new(quiet)
+			config.LogLevel = new(logLevel)
+		case "log-file", "w":
+			config.LogFile = new(logFile)
+		case "progress", "p":
+			config.Progress = new(ConfigProgressType(progress))
 		case "output", "o":
 			config.Output = new(ConfigOutputType(output))
 		case "dry-run", "z":
@@ -265,7 +279,8 @@ func (parser ConfigCLIParser) PrintHelp() {
 		cliUsageText+"\n",
 		Defaults.ShowConfig,
 		Defaults.Concurrency,
-		Defaults.Quiet,
+		Defaults.LogLevel,
+		Defaults.Progress,
 		Defaults.Output,
 		Defaults.DryRun,
 

internal/config/config.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"net/url"
 	"os"
+	"path/filepath"
 	"slices"
 	"strconv"
 	"strings"
@@ -17,6 +18,7 @@ import (
 	"github.com/charmbracelet/glamour/styles"
 	"github.com/charmbracelet/lipgloss"
 	"github.com/charmbracelet/x/term"
+	"go.aykhans.me/sarin/internal/sarin"
 	"go.aykhans.me/sarin/internal/script"
 	"go.aykhans.me/sarin/internal/types"
 	"go.aykhans.me/sarin/internal/version"
@@ -31,25 +33,28 @@ var Defaults = struct {
 	RequestTimeout time.Duration
 	Concurrency    uint
 	ShowConfig     bool
-	Quiet          bool
+	Progress       ConfigProgressType
 	Insecure       bool
 	Output         ConfigOutputType
 	DryRun         bool
+	LogLevel       string
 }{
 	UserAgent:      "Sarin/" + version.Version,
 	Method:         "GET",
 	RequestTimeout: time.Second * 10,
 	Concurrency:    1,
 	ShowConfig:     false,
-	Quiet:          false,
+	Progress:       ConfigProgressTypeBar,
 	Insecure:       false,
 	Output:         ConfigOutputTypeTable,
 	DryRun:         false,
+	LogLevel:       "error",
 }
 
 var (
 	ValidProxySchemes      = []string{"http", "https", "socks5", "socks5h"}
 	ValidRequestURLSchemes = []string{"http", "https"}
+	ValidLogLevels         = []string{"info", "error"}
 )
 
 var (
@@ -70,27 +75,36 @@ var (
 	ConfigOutputTypeNone  ConfigOutputType = "none"
 )
 
+type ConfigProgressType string
+
+var (
+	ConfigProgressTypeBar  ConfigProgressType = "bar"
+	ConfigProgressTypeNone ConfigProgressType = "none"
+)
+
 type Config struct {
-	ShowConfig  *bool              `yaml:"showConfig,omitempty"`
+	ShowConfig  *bool               `yaml:"showConfig,omitempty"`
-	Files       []types.ConfigFile `yaml:"files,omitempty"`
+	Files       []types.ConfigFile  `yaml:"files,omitempty"`
-	Methods     []string           `yaml:"methods,omitempty"`
+	Methods     []string            `yaml:"methods,omitempty"`
-	URL         *url.URL           `yaml:"url,omitempty"`
+	URL         *url.URL            `yaml:"url,omitempty"`
-	Timeout     *time.Duration     `yaml:"timeout,omitempty"`
+	Timeout     *time.Duration      `yaml:"timeout,omitempty"`
-	Concurrency *uint              `yaml:"concurrency,omitempty"`
+	Concurrency *uint               `yaml:"concurrency,omitempty"`
-	Requests    *uint64            `yaml:"requests,omitempty"`
+	Requests    *uint64             `yaml:"requests,omitempty"`
-	Duration    *time.Duration     `yaml:"duration,omitempty"`
+	Duration    *time.Duration      `yaml:"duration,omitempty"`
-	Quiet       *bool              `yaml:"quiet,omitempty"`
+	Progress    *ConfigProgressType `yaml:"progress,omitempty"`
-	Output      *ConfigOutputType  `yaml:"output,omitempty"`
+	Output      *ConfigOutputType   `yaml:"output,omitempty"`
-	Insecure    *bool              `yaml:"insecure,omitempty"`
+	Insecure    *bool               `yaml:"insecure,omitempty"`
-	DryRun      *bool              `yaml:"dryRun,omitempty"`
+	DryRun      *bool               `yaml:"dryRun,omitempty"`
-	Params      types.Params       `yaml:"params,omitempty"`
+	Params      types.Params        `yaml:"params,omitempty"`
-	Headers     types.Headers      `yaml:"headers,omitempty"`
+	Headers     types.Headers       `yaml:"headers,omitempty"`
-	Cookies     types.Cookies      `yaml:"cookies,omitempty"`
+	Cookies     types.Cookies       `yaml:"cookies,omitempty"`
-	Bodies      []string           `yaml:"bodies,omitempty"`
+	Bodies      []string            `yaml:"bodies,omitempty"`
-	Proxies     types.Proxies      `yaml:"proxies,omitempty"`
+	Proxies     types.Proxies       `yaml:"proxies,omitempty"`
-	Values      []string           `yaml:"values,omitempty"`
+	Values      []string            `yaml:"values,omitempty"`
-	Lua         []string           `yaml:"lua,omitempty"`
+	Lua         []string            `yaml:"lua,omitempty"`
-	Js          []string           `yaml:"js,omitempty"`
+	Js          []string            `yaml:"js,omitempty"`
+	LogLevel    *string             `yaml:"logLevel,omitempty"`
+	LogFile     *string             `yaml:"logFile,omitempty"`
 }
 
 func (config Config) MarshalYAML() (any, error) {
@@ -173,8 +187,8 @@ func (config Config) MarshalYAML() (any, error) {
 	if config.Duration != nil {
 		addField(content, "duration", toNode(*config.Duration), "")
 	}
-	if config.Quiet != nil {
+	if config.Progress != nil {
-		addField(content, "quiet", toNode(*config.Quiet), "")
+		addField(content, "progress", toNode(string(*config.Progress)), "")
 	}
 	if config.Output != nil {
 		addField(content, "output", toNode(string(*config.Output)), "")
@@ -221,6 +235,13 @@ func (config Config) MarshalYAML() (any, error) {
 	addStringSlice(content, "values", config.Values, false)
 	addStringSlice(content, "lua", config.Lua, false)
 	addStringSlice(content, "js", config.Js, false)
+	if config.LogLevel != nil {
+		addField(content, "logLevel", toNode(*config.LogLevel), "")
+	}
+
+	if config.LogFile != nil {
+		addField(content, "logFile", toNode(*config.LogFile), "")
+	}
 
 	return root, nil
 }
@@ -295,8 +316,8 @@ func (config *Config) Merge(newConfig *Config) {
 	if newConfig.ShowConfig != nil {
 		config.ShowConfig = newConfig.ShowConfig
 	}
-	if newConfig.Quiet != nil {
+	if newConfig.Progress != nil {
-		config.Quiet = newConfig.Quiet
+		config.Progress = newConfig.Progress
 	}
 	if newConfig.Output != nil {
 		config.Output = newConfig.Output
@@ -331,6 +352,12 @@ func (config *Config) Merge(newConfig *Config) {
 	if len(newConfig.Js) != 0 {
 		config.Js = append(config.Js, newConfig.Js...)
 	}
+	if newConfig.LogLevel != nil {
+		config.LogLevel = newConfig.LogLevel
+	}
+	if newConfig.LogFile != nil {
+		config.LogFile = newConfig.LogFile
+	}
 }
 
 func (config *Config) SetDefaults() {
@@ -361,8 +388,8 @@ func (config *Config) SetDefaults() {
 	if config.ShowConfig == nil {
 		config.ShowConfig = new(Defaults.ShowConfig)
 	}
-	if config.Quiet == nil {
+	if config.Progress == nil {
-		config.Quiet = new(Defaults.Quiet)
+		config.Progress = new(Defaults.Progress)
 	}
 	if config.Insecure == nil {
 		config.Insecure = new(Defaults.Insecure)
@@ -377,6 +404,14 @@ func (config *Config) SetDefaults() {
 	if config.Output == nil {
 		config.Output = new(Defaults.Output)
 	}
+
+	if config.LogLevel == nil {
+		config.LogLevel = new(Defaults.LogLevel)
+	}
+
+	if config.LogFile == nil {
+		config.LogFile = new("")
+	}
 }
 
 // Validate validates the config fields.
@@ -426,8 +461,21 @@ func (config Config) Validate() error {
 		validationErrors = append(validationErrors, types.NewFieldValidationError("ShowConfig", "", errors.New("showConfig field is required")))
 	}
 
-	if config.Quiet == nil {
+	if config.Progress == nil {
-		validationErrors = append(validationErrors, types.NewFieldValidationError("Quiet", "", errors.New("quiet field is required")))
+		validationErrors = append(validationErrors, types.NewFieldValidationError("Progress", "", errors.New("progress field is required")))
+	} else {
+		switch *config.Progress {
+		case ConfigProgressTypeBar, ConfigProgressTypeNone:
+		default:
+			validationErrors = append(
+				validationErrors,
+				types.NewFieldValidationError(
+					"Progress",
+					string(*config.Progress),
+					fmt.Errorf("progress must be one of: %s, %s", ConfigProgressTypeBar, ConfigProgressTypeNone),
+				),
+			)
+		}
 	}
 
 	if config.Output == nil {
@@ -460,6 +508,36 @@ func (config Config) Validate() error {
 		validationErrors = append(validationErrors, types.NewFieldValidationError("DryRun", "", errors.New("dryRun field is required")))
 	}
 
+	if config.LogLevel != nil {
+		for i, level := range sarin.SplitLogLevels(*config.LogLevel) {
+			if !slices.Contains(ValidLogLevels, level) {
+				validationErrors = append(
+					validationErrors,
+					types.NewFieldValidationError(
+						fmt.Sprintf("LogLevel[%d]", i),
+						level,
+						fmt.Errorf("log level must be one of: %s", strings.Join(ValidLogLevels, ", ")),
+					),
+				)
+			}
+		}
+	}
+
+	if config.LogFile != nil && *config.LogFile != "" {
+		dir := filepath.Dir(*config.LogFile)
+		if info, err := os.Stat(dir); err != nil {
+			validationErrors = append(
+				validationErrors,
+				types.NewFieldValidationError("LogFile", *config.LogFile, fmt.Errorf("parent directory %q is not accessible", dir)),
+			)
+		} else if !info.IsDir() {
+			validationErrors = append(
+				validationErrors,
+				types.NewFieldValidationError("LogFile", *config.LogFile, fmt.Errorf("parent path %q is not a directory", dir)),
+			)
+		}
+	}
+
 	for i, proxy := range config.Proxies {
 		if !slices.Contains(ValidProxySchemes, proxy.Scheme) {
 			validationErrors = append(

internal/config/env.go

@@ -49,74 +49,6 @@ func (parser ConfigENVParser) Parse() (*Config, error) {
 		config.Files = append(config.Files, *types.ParseConfigFile(configFile))
 	}
 
-	if quiet := parser.getEnv("QUIET"); quiet != "" {
-		quietParsed, err := utilsParse.ParseString[bool](quiet)
-		if err != nil {
-			fieldParseErrors = append(
-				fieldParseErrors,
-				types.NewFieldParseError(
-					parser.getFullEnvName("QUIET"),
-					quiet,
-					errors.New("invalid value for boolean, expected 'true' or 'false'"),
-				),
-			)
-		} else {
-			config.Quiet = &quietParsed
-		}
-	}
-
-	if output := parser.getEnv("OUTPUT"); output != "" {
-		config.Output = new(ConfigOutputType(output))
-	}
-
-	if insecure := parser.getEnv("INSECURE"); insecure != "" {
-		insecureParsed, err := utilsParse.ParseString[bool](insecure)
-		if err != nil {
-			fieldParseErrors = append(
-				fieldParseErrors,
-				types.NewFieldParseError(
-					parser.getFullEnvName("INSECURE"),
-					insecure,
-					errors.New("invalid value for boolean, expected 'true' or 'false'"),
-				),
-			)
-		} else {
-			config.Insecure = &insecureParsed
-		}
-	}
-
-	if dryRun := parser.getEnv("DRY_RUN"); dryRun != "" {
-		dryRunParsed, err := utilsParse.ParseString[bool](dryRun)
-		if err != nil {
-			fieldParseErrors = append(
-				fieldParseErrors,
-				types.NewFieldParseError(
-					parser.getFullEnvName("DRY_RUN"),
-					dryRun,
-					errors.New("invalid value for boolean, expected 'true' or 'false'"),
-				),
-			)
-		} else {
-			config.DryRun = &dryRunParsed
-		}
-	}
-
-	if method := parser.getEnv("METHOD"); method != "" {
-		config.Methods = []string{method}
-	}
-
-	if urlEnv := parser.getEnv("URL"); urlEnv != "" {
-		urlEnvParsed, err := url.Parse(urlEnv)
-		if err != nil {
-			fieldParseErrors = append(
-				fieldParseErrors,
-				types.NewFieldParseError(parser.getFullEnvName("URL"), urlEnv, err),
-			)
-		} else {
-			config.URL = urlEnvParsed
-		}
-	}
-
 	if concurrency := parser.getEnv("CONCURRENCY"); concurrency != "" {
 		concurrencyParsed, err := utilsParse.ParseString[uint](concurrency)
 		if err != nil {
@@ -165,22 +97,58 @@ func (parser ConfigENVParser) Parse() (*Config, error) {
 		}
 	}
 
-	if timeout := parser.getEnv("TIMEOUT"); timeout != "" {
+	if logLevel := parser.getEnv("LOG_LEVEL"); logLevel != "" {
-		timeoutParsed, err := utilsParse.ParseString[time.Duration](timeout)
+		config.LogLevel = new(logLevel)
+	}
+
+	if logFile := parser.getEnv("LOG_FILE"); logFile != "" {
+		config.LogFile = new(logFile)
+	}
+
+	if progress := parser.getEnv("PROGRESS"); progress != "" {
+		config.Progress = new(ConfigProgressType(progress))
+	}
+
+	if output := parser.getEnv("OUTPUT"); output != "" {
+		config.Output = new(ConfigOutputType(output))
+	}
+
+	if dryRun := parser.getEnv("DRY_RUN"); dryRun != "" {
+		dryRunParsed, err := utilsParse.ParseString[bool](dryRun)
 		if err != nil {
 			fieldParseErrors = append(
 				fieldParseErrors,
 				types.NewFieldParseError(
-					parser.getFullEnvName("TIMEOUT"),
+					parser.getFullEnvName("DRY_RUN"),
-					timeout,
+					dryRun,
-					errors.New("invalid value for duration, expected a duration string (e.g., '10s', '1h30m')"),
+					errors.New("invalid value for boolean, expected 'true' or 'false'"),
 				),
 			)
 		} else {
-			config.Timeout = &timeoutParsed
+			config.DryRun = &dryRunParsed
 		}
 	}
 
+	if urlEnv := parser.getEnv("URL"); urlEnv != "" {
+		urlEnvParsed, err := url.Parse(urlEnv)
+		if err != nil {
+			fieldParseErrors = append(
+				fieldParseErrors,
+				types.NewFieldParseError(parser.getFullEnvName("URL"), urlEnv, err),
+			)
+		} else {
+			config.URL = urlEnvParsed
+		}
+	}
+
+	if method := parser.getEnv("METHOD"); method != "" {
+		config.Methods = []string{method}
+	}
+
+	if body := parser.getEnv("BODY"); body != "" {
+		config.Bodies = []string{body}
+	}
+
 	if param := parser.getEnv("PARAM"); param != "" {
 		config.Params.Parse(param)
 	}
@@ -193,10 +161,6 @@ func (parser ConfigENVParser) Parse() (*Config, error) {
 		config.Cookies.Parse(cookie)
 	}
 
-	if body := parser.getEnv("BODY"); body != "" {
-		config.Bodies = []string{body}
-	}
-
 	if proxy := parser.getEnv("PROXY"); proxy != "" {
 		err := config.Proxies.Parse(proxy)
 		if err != nil {
@@ -215,6 +179,38 @@ func (parser ConfigENVParser) Parse() (*Config, error) {
 		config.Values = []string{values}
 	}
 
+	if timeout := parser.getEnv("TIMEOUT"); timeout != "" {
+		timeoutParsed, err := utilsParse.ParseString[time.Duration](timeout)
+		if err != nil {
+			fieldParseErrors = append(
+				fieldParseErrors,
+				types.NewFieldParseError(
+					parser.getFullEnvName("TIMEOUT"),
+					timeout,
+					errors.New("invalid value for duration, expected a duration string (e.g., '10s', '1h30m')"),
+				),
+			)
+		} else {
+			config.Timeout = &timeoutParsed
+		}
+	}
+
+	if insecure := parser.getEnv("INSECURE"); insecure != "" {
+		insecureParsed, err := utilsParse.ParseString[bool](insecure)
+		if err != nil {
+			fieldParseErrors = append(
+				fieldParseErrors,
+				types.NewFieldParseError(
+					parser.getFullEnvName("INSECURE"),
+					insecure,
+					errors.New("invalid value for boolean, expected 'true' or 'false'"),
+				),
+			)
+		} else {
+			config.Insecure = &insecureParsed
+		}
+	}
+
 	if lua := parser.getEnv("LUA"); lua != "" {
 		config.Lua = []string{lua}
 	}

internal/config/file.go

@@ -192,24 +192,26 @@ func (kv *keyValuesField) unmarshalMapping(node *yaml.Node) error {
 }
 
 type configYAML struct {
+	ShowConfig   *bool              `yaml:"showConfig"`
 	ConfigFiles  stringOrSliceField `yaml:"configFile"`
-	Method       stringOrSliceField `yaml:"method"`
-	URL          *string            `yaml:"url"`
-	Timeout      *time.Duration     `yaml:"timeout"`
 	Concurrency  *uint              `yaml:"concurrency"`
 	RequestCount *uint64            `yaml:"requests"`
 	Duration     *time.Duration     `yaml:"duration"`
-	Quiet        *bool              `yaml:"quiet"`
+	LogLevel     *string            `yaml:"logLevel"`
+	LogFile      *string            `yaml:"logFile"`
+	Progress     *string            `yaml:"progress"`
 	Output       *string            `yaml:"output"`
-	Insecure     *bool              `yaml:"insecure"`
-	ShowConfig   *bool              `yaml:"showConfig"`
 	DryRun       *bool              `yaml:"dryRun"`
+	URL          *string            `yaml:"url"`
+	Method       stringOrSliceField `yaml:"method"`
+	Bodies       stringOrSliceField `yaml:"body"`
 	Params       keyValuesField     `yaml:"params"`
 	Headers      keyValuesField     `yaml:"headers"`
 	Cookies      keyValuesField     `yaml:"cookies"`
-	Bodies       stringOrSliceField `yaml:"body"`
 	Proxies      stringOrSliceField `yaml:"proxy"`
 	Values       stringOrSliceField `yaml:"values"`
+	Timeout      *time.Duration     `yaml:"timeout"`
+	Insecure     *bool              `yaml:"insecure"`
 	Lua          stringOrSliceField `yaml:"lua"`
 	Js           stringOrSliceField `yaml:"js"`
 }
@@ -231,33 +233,7 @@ func (parser ConfigFileParser) ParseYAML(data []byte) (*Config, error) {
 
 	var fieldParseErrors []types.FieldParseError
 
-	config.Methods = append(config.Methods, parsedData.Method...)
-	config.Timeout = parsedData.Timeout
-	config.Concurrency = parsedData.Concurrency
-	config.Requests = parsedData.RequestCount
-	config.Duration = parsedData.Duration
 	config.ShowConfig = parsedData.ShowConfig
-	config.Quiet = parsedData.Quiet
-
-	if parsedData.Output != nil {
-		config.Output = new(ConfigOutputType(*parsedData.Output))
-	}
-
-	config.Insecure = parsedData.Insecure
-	config.DryRun = parsedData.DryRun
-	for _, kv := range parsedData.Params {
-		config.Params = append(config.Params, types.Param(kv))
-	}
-	for _, kv := range parsedData.Headers {
-		config.Headers = append(config.Headers, types.Header(kv))
-	}
-	for _, kv := range parsedData.Cookies {
-		config.Cookies = append(config.Cookies, types.Cookie(kv))
-	}
-	config.Bodies = append(config.Bodies, parsedData.Bodies...)
-	config.Values = append(config.Values, parsedData.Values...)
-	config.Lua = append(config.Lua, parsedData.Lua...)
-	config.Js = append(config.Js, parsedData.Js...)
 
 	if len(parsedData.ConfigFiles) > 0 {
 		for _, configFile := range parsedData.ConfigFiles {
@@ -265,6 +241,22 @@ func (parser ConfigFileParser) ParseYAML(data []byte) (*Config, error) {
 		}
 	}
 
+	config.Concurrency = parsedData.Concurrency
+	config.Requests = parsedData.RequestCount
+	config.Duration = parsedData.Duration
+	config.LogLevel = parsedData.LogLevel
+	config.LogFile = parsedData.LogFile
+
+	if parsedData.Progress != nil {
+		config.Progress = new(ConfigProgressType(*parsedData.Progress))
+	}
+
+	if parsedData.Output != nil {
+		config.Output = new(ConfigOutputType(*parsedData.Output))
+	}
+
+	config.DryRun = parsedData.DryRun
+
 	if parsedData.URL != nil {
 		urlParsed, err := url.Parse(*parsedData.URL)
 		if err != nil {
@@ -274,6 +266,18 @@ func (parser ConfigFileParser) ParseYAML(data []byte) (*Config, error) {
 		}
 	}
 
+	config.Methods = append(config.Methods, parsedData.Method...)
+	config.Bodies = append(config.Bodies, parsedData.Bodies...)
+	for _, kv := range parsedData.Params {
+		config.Params = append(config.Params, types.Param(kv))
+	}
+	for _, kv := range parsedData.Headers {
+		config.Headers = append(config.Headers, types.Header(kv))
+	}
+	for _, kv := range parsedData.Cookies {
+		config.Cookies = append(config.Cookies, types.Cookie(kv))
+	}
+
 	for i, proxy := range parsedData.Proxies {
 		err := config.Proxies.Parse(proxy)
 		if err != nil {
@@ -284,6 +288,12 @@ func (parser ConfigFileParser) ParseYAML(data []byte) (*Config, error) {
 		}
 	}
 
+	config.Values = append(config.Values, parsedData.Values...)
+	config.Timeout = parsedData.Timeout
+	config.Insecure = parsedData.Insecure
+	config.Lua = append(config.Lua, parsedData.Lua...)
+	config.Js = append(config.Js, parsedData.Js...)
+
 	if len(fieldParseErrors) > 0 {
 		return nil, types.NewFieldParseErrors(fieldParseErrors)
 	}

internal/sarin/runner.go

@@ -2,8 +2,13 @@ package sarin
 
 import (
 	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"log"
 	"net/url"
 	"os"
+	"strings"
 	"sync"
 	"sync/atomic"
 	"time"
@@ -14,20 +19,153 @@ import (
 	"go.aykhans.me/sarin/internal/types"
 )
 
-type runtimeMessageLevel uint8
+type runtimeLogLevel uint8
 
 const (
-	runtimeMessageLevelWarning runtimeMessageLevel = iota
+	runtimeLogLevelInfo runtimeLogLevel = iota
-	runtimeMessageLevelError
+	runtimeLogLevelError
 )
 
-type runtimeMessage struct {
+type runtimeLog struct {
 	timestamp time.Time
-	level     runtimeMessageLevel
+	level     runtimeLogLevel
 	text      string
 }
 
-type messageSender func(level runtimeMessageLevel, text string)
+type runtimeLogger func(level runtimeLogLevel, text string)
+
+// SplitLogLevels parses a comma-separated log-level string into a deduplicated
+// slice of level tokens (surrounding whitespace trimmed, empties dropped). Level
+// names are matched case-sensitively, like the other enum options.
+func SplitLogLevels(levels string) []string {
+	var out []string
+	seen := make(map[string]bool)
+	for part := range strings.SplitSeq(levels, ",") {
+		token := strings.TrimSpace(part)
+		if token == "" || seen[token] {
+			continue
+		}
+		seen[token] = true
+		out = append(out, token)
+	}
+	return out
+}
+
+// respLogger logs a single completed response.
+type respLogger func(duration time.Duration, resp *fasthttp.Response)
+
+func noopLog(runtimeLogLevel, string)               {}
+func noopRespLog(time.Duration, *fasthttp.Response) {}
+
+// gateSendLog wraps emit with level filtering decided once from the enabled
+// levels. It stays general (any level filters correctly) while avoiding a
+// per-log check when both levels are on and any work at all when both are off.
+func gateSendLog(logInfo, logError bool, emit func(level runtimeLogLevel, text string)) runtimeLogger {
+	switch {
+	case logInfo && logError:
+		return emit
+	case logInfo:
+		return func(level runtimeLogLevel, text string) {
+			if level == runtimeLogLevelInfo {
+				emit(level, text)
+			}
+		}
+	case logError:
+		return func(level runtimeLogLevel, text string) {
+			if level == runtimeLogLevelError {
+				emit(level, text)
+			}
+		}
+	default:
+		return noopLog
+	}
+}
+
+// respBodySnippetLen bounds how many bytes of the body the compact (TUI)
+// rendering shows.
+const respBodySnippetLen = 100
+
+// formatRuntimeLogLine renders a runtime log as a plain (unstyled) line for
+// stderr output. ANSI styling is left to the TUI.
+func formatRuntimeLogLine(timestamp time.Time, level runtimeLogLevel, text string) string {
+	levelStr := "ERROR"
+	if level == runtimeLogLevelInfo {
+		levelStr = "INFO"
+	}
+	return "[" + timestamp.Format("15:04:05") + "] " + levelStr + ": " + text
+}
+
+// respToLog renders a response as a compact one-line summary for the TUI log box
+// (the "[time] INFO:" prefix is added by the TUI).
+func respToLog(duration time.Duration, resp *fasthttp.Response) string {
+	var sb strings.Builder
+	sb.WriteString(statusCodeToString(resp.StatusCode()))
+	sb.WriteString(" ")
+	sb.WriteString(Duration(duration).String())
+	if snippet := bodySnippet(resp.Body(), respBodySnippetLen); snippet != "" {
+		sb.WriteString(" | ")
+		sb.WriteString(snippet)
+	}
+	return sb.String()
+}
+
+type respLogEntry struct {
+	Status   int                 `json:"status"`
+	Duration string              `json:"duration"`
+	Headers  map[string][]string `json:"headers,omitempty"`
+	Body     string              `json:"body,omitempty"`
+}
+
+// respToLogJSON renders a response as a single, self-contained JSON line so the
+// stderr stream stays valid NDJSON (pipeable to jq or any consumer).
+func respToLogJSON(duration time.Duration, resp *fasthttp.Response) string {
+	entry := respLogEntry{
+		Status:   resp.StatusCode(),
+		Duration: Duration(duration).String(),
+		Headers:  collectRespHeaders(resp),
+		Body:     string(resp.Body()),
+	}
+	data, err := json.Marshal(entry)
+	if err != nil {
+		return `{"error":"failed to marshal response log"}`
+	}
+	return string(data)
+}
+
+func collectRespHeaders(resp *fasthttp.Response) map[string][]string {
+	headers := make(map[string][]string)
+	for key, value := range resp.Header.All() {
+		k := string(key)
+		headers[k] = append(headers[k], string(value))
+	}
+	return headers
+}
+
+// bodySnippet returns the first maxLen bytes of body collapsed onto a single
+// line (control characters replaced with spaces), with an ellipsis when truncated.
+func bodySnippet(body []byte, maxLen int) string {
+	if len(body) == 0 {
+		return ""
+	}
+
+	truncated := false
+	if len(body) > maxLen {
+		body = body[:maxLen]
+		truncated = true
+	}
+
+	s := strings.Map(func(r rune) rune {
+		if r == '\n' || r == '\r' || r == '\t' {
+			return ' '
+		}
+		return r
+	}, string(body))
+
+	if truncated {
+		s += "..."
+	}
+	return s
+}
 
 type sarin struct {
 	workers        uint
@@ -40,11 +178,14 @@ type sarin struct {
 	totalRequests  *uint64
 	totalDuration  *time.Duration
 	timeout        time.Duration
-	quiet          bool
+	showProgress   bool
 	skipCertVerify bool
 	values         []string
 	collectStats   bool
 	dryRun         bool
+	logInfo        bool
+	logError       bool
+	logFile        string
 
 	hostClients []*fasthttp.HostClient
 	responses   *SarinResponseData
@@ -65,7 +206,7 @@ func NewSarin(
 	workers uint,
 	totalRequests *uint64,
 	totalDuration *time.Duration,
-	quiet bool,
+	showProgress bool,
 	skipCertVerify bool,
 	params types.Params,
 	headers types.Headers,
@@ -75,6 +216,8 @@ func NewSarin(
 	values []string,
 	collectStats bool,
 	dryRun bool,
+	logLevel string,
+	logFile string,
 	luaScripts []string,
 	jsScripts []string,
 ) (*sarin, error) {
@@ -82,6 +225,17 @@ func NewSarin(
 		workers = 1
 	}
 
+	// Resolve which log levels are enabled once, up front.
+	var logInfo, logError bool
+	for _, level := range SplitLogLevels(logLevel) {
+		switch level {
+		case "info":
+			logInfo = true
+		case "error":
+			logError = true
+		}
+	}
+
 	hostClients, err := newHostClients(ctx, timeout, proxies, workers, requestURL, skipCertVerify)
 	if err != nil {
 		return nil, err
@@ -111,11 +265,14 @@ func NewSarin(
 		totalRequests:  totalRequests,
 		totalDuration:  totalDuration,
 		timeout:        timeout,
-		quiet:          quiet,
+		showProgress:   showProgress,
 		skipCertVerify: skipCertVerify,
 		values:         values,
 		collectStats:   collectStats,
 		dryRun:         dryRun,
+		logInfo:        logInfo,
+		logError:       logError,
+		logFile:        logFile,
 		hostClients:    hostClients,
 		fileCache:      NewFileCache(time.Second * 10),
 		scriptChain:    scriptChain,
@@ -128,73 +285,95 @@ func NewSarin(
 	return srn, nil
 }
 
-func (q sarin) GetResponses() *SarinResponseData {
+func (s sarin) GetResponses() *SarinResponseData {
-	return q.responses
+	return s.responses
 }
 
-func (q sarin) Start(ctx context.Context, stopCtrl *StopController) {
+func (s sarin) Start(ctx context.Context, stopCtrl *StopController) {
 	jobsCtx, jobsCancel := context.WithCancel(ctx)
 
 	var workersWG sync.WaitGroup
-	jobsCh := make(chan struct{}, max(q.workers, 1))
+	jobsCh := make(chan struct{}, max(s.workers, 1))
 
 	var counter atomic.Uint64
 
 	totalRequests := uint64(0)
-	if q.totalRequests != nil {
+	if s.totalRequests != nil {
-		totalRequests = *q.totalRequests
+		totalRequests = *s.totalRequests
 	}
 
-	var streamCtx context.Context
+	onTerminal := term.IsTerminal(os.Stdout.Fd())
-	var streamCancel context.CancelFunc
+	// The progress bar needs an interactive terminal to render.
-	var streamCh chan struct{}
+	showProgressBar := s.showProgress && onTerminal
-	var messageChannel chan runtimeMessage
+	// The bubbletea TUI hosts the bar and/or the live log box, so it runs whenever
-	var sendMessage messageSender
+	// either has something to show: the bar, or logs that would land in the box
+	// (i.e. logs are enabled and not redirected to a file).
+	runTUI := showProgressBar || (onTerminal && (s.logInfo || s.logError) && s.logFile == "")
 
-	if !q.quiet && !term.IsTerminal(os.Stdout.Fd()) {
+	// Open the log file up front, before registering any defer, so a bad path
-		q.quiet = true
+	// exits cleanly.
+	var logFile *os.File
+	if s.logFile != "" {
+		f, err := os.OpenFile(s.logFile, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0o600)
+		if err != nil {
+			fmt.Fprintln(os.Stderr, "failed to open log file "+s.logFile+": "+err.Error())
+			os.Exit(1)
+		}
+		defer f.Close() //nolint:errcheck
+		logFile = f
 	}
 
-	if q.quiet {
+	var (
-		sendMessage = func(level runtimeMessageLevel, text string) {}
+		streamCtx     context.Context
-	} else {
+		streamCancel  context.CancelFunc
+		streamCh      chan struct{}
+		tuiLogChannel chan runtimeLog
+	)
+	if runTUI {
 		streamCtx, streamCancel = context.WithCancel(context.Background())
 		defer streamCancel()
 		streamCh = make(chan struct{})
-		messageChannel = make(chan runtimeMessage, max(q.workers, 1))
+		tuiLogChannel = make(chan runtimeLog, max(s.workers, 1))
-		sendMessage = func(level runtimeMessageLevel, text string) {
+	}
-			messageChannel <- runtimeMessage{
+
-				timestamp: time.Now(),
+	// Route logs: to the file if given, else to the TUI log box while it runs,
-				level:     level,
+	// otherwise to stderr.
-				text:      text,
+	var (
-			}
+		sendLog     runtimeLogger
-		}
+		sendRespLog respLogger
+	)
+	switch {
+	case logFile != nil:
+		sendLog, sendRespLog = s.newWriterLog(logFile)
+	case runTUI:
+		sendLog, sendRespLog = s.newChannelLog(tuiLogChannel)
+	default:
+		sendLog, sendRespLog = s.newWriterLog(os.Stderr)
 	}
 
 	// Start workers
-	q.startWorkers(&workersWG, jobsCh, q.hostClients, &counter, sendMessage)
+	s.startWorkers(&workersWG, jobsCh, s.hostClients, &counter, sendLog, sendRespLog)
 
-	if !q.quiet {
+	if runTUI {
-		// Start streaming to terminal
 		//nolint:contextcheck // streamCtx must remain active until all workers complete to ensure all collected data is streamed
-		go q.streamProgress(streamCtx, stopCtrl, streamCh, totalRequests, &counter, messageChannel)
+		go s.streamProgress(streamCtx, stopCtrl, streamCh, totalRequests, &counter, tuiLogChannel, showProgressBar)
 	}
 
 	// Setup duration-based cancellation
-	q.setupDurationTimeout(ctx, jobsCancel)
+	s.setupDurationTimeout(ctx, jobsCancel)
 	// Distribute jobs to workers.
 	// This blocks until all jobs are sent or the context is canceled.
-	q.sendJobs(jobsCtx, jobsCh)
+	s.sendJobs(jobsCtx, jobsCh)
 
 	// Close the jobs channel so workers stop after completing their current job
 	close(jobsCh)
 	// Wait until all workers stopped
 	workersWG.Wait()
-	if messageChannel != nil {
+	if tuiLogChannel != nil {
-		close(messageChannel)
+		close(tuiLogChannel)
 	}
 
-	if !q.quiet {
+	if runTUI {
 		// Stop the progress streaming
 		streamCancel()
 		// Wait until progress streaming has completely stopped
@@ -202,6 +381,45 @@ func (q sarin) Start(ctx context.Context, stopCtrl *StopController) {
 	}
 }
 
+// newWriterLog builds the loggers that write formatted lines to w (a log file or
+// stderr). sendLog stays general (it filters by each log's level); sendRespLog
+// only ever emits info, so its decision is baked once into a no-op when off.
+func (s sarin) newWriterLog(w io.Writer) (runtimeLogger, respLogger) {
+	// log.Logger serializes writes with its own mutex, so concurrent workers
+	// won't interleave lines.
+	logger := log.New(w, "", 0)
+
+	sendLog := gateSendLog(s.logInfo, s.logError, func(level runtimeLogLevel, text string) {
+		logger.Println(formatRuntimeLogLine(time.Now(), level, text))
+	})
+
+	var sendRespLog respLogger = noopRespLog
+	if s.logInfo {
+		sendRespLog = func(duration time.Duration, resp *fasthttp.Response) {
+			logger.Println(formatRuntimeLogLine(time.Now(), runtimeLogLevelInfo, respToLogJSON(duration, resp)))
+		}
+	}
+
+	return sendLog, sendRespLog
+}
+
+// newChannelLog builds the loggers that feed the TUI log box through ch, with the
+// same gating as newWriterLog.
+func (s sarin) newChannelLog(ch chan<- runtimeLog) (runtimeLogger, respLogger) {
+	sendLog := gateSendLog(s.logInfo, s.logError, func(level runtimeLogLevel, text string) {
+		ch <- runtimeLog{timestamp: time.Now(), level: level, text: text}
+	})
+
+	var sendRespLog respLogger = noopRespLog
+	if s.logInfo {
+		sendRespLog = func(duration time.Duration, resp *fasthttp.Response) {
+			ch <- runtimeLog{timestamp: time.Now(), level: runtimeLogLevelInfo, text: respToLog(duration, resp)}
+		}
+	}
+
+	return sendLog, sendRespLog
+}
+
 // newHostClients initializes HTTP clients for the given configuration.
 // It can return the following errors:
 // - types.ProxyDialError
@@ -228,18 +446,18 @@ func newHostClients(
 	)
 }
 
-func (q sarin) startWorkers(wg *sync.WaitGroup, jobs <-chan struct{}, hostClients []*fasthttp.HostClient, counter *atomic.Uint64, sendMessage messageSender) {
+func (s sarin) startWorkers(wg *sync.WaitGroup, jobs <-chan struct{}, hostClients []*fasthttp.HostClient, counter *atomic.Uint64, sendLog runtimeLogger, sendRespLog respLogger) {
-	for range max(q.workers, 1) {
+	for range max(s.workers, 1) {
 		wg.Go(func() {
-			q.Worker(jobs, NewHostClientGenerator(hostClients...), counter, sendMessage)
+			s.Worker(jobs, NewHostClientGenerator(hostClients...), counter, sendLog, sendRespLog)
 		})
 	}
 }
 
-func (q sarin) setupDurationTimeout(ctx context.Context, cancel context.CancelFunc) {
+func (s sarin) setupDurationTimeout(ctx context.Context, cancel context.CancelFunc) {
-	if q.totalDuration != nil {
+	if s.totalDuration != nil {
 		go func() {
-			timer := time.NewTimer(*q.totalDuration)
+			timer := time.NewTimer(*s.totalDuration)
 			defer timer.Stop()
 			select {
 			case <-timer.C:
@@ -251,9 +469,9 @@ func (q sarin) setupDurationTimeout(ctx context.Context, cancel context.CancelFu
 	}
 }
 
-func (q sarin) sendJobs(ctx context.Context, jobs chan<- struct{}) {
+func (s sarin) sendJobs(ctx context.Context, jobs chan<- struct{}) {
-	if q.totalRequests != nil && *q.totalRequests > 0 {
+	if s.totalRequests != nil && *s.totalRequests > 0 {
-		for range *q.totalRequests {
+		for range *s.totalRequests {
 			if ctx.Err() != nil {
 				break
 			}

internal/sarin/tui.go

@@ -16,24 +16,61 @@ import (
 type tickMsg time.Time
 
 var (
-	helpStyle           = lipgloss.NewStyle().Foreground(lipgloss.Color("#d1d1d1"))
+	helpStyle  = lipgloss.NewStyle().Foreground(lipgloss.Color("#d1d1d1"))
-	errorStyle          = lipgloss.NewStyle().Foreground(lipgloss.Color("#FC5B5B")).Bold(true)
+	errorStyle = lipgloss.NewStyle().Foreground(lipgloss.Color("#FC5B5B")).Bold(true)
-	warningStyle        = lipgloss.NewStyle().Foreground(lipgloss.Color("#FFD93D")).Bold(true)
+	infoStyle  = lipgloss.NewStyle().Foreground(lipgloss.Color("#5BC0FC")).Bold(true)
-	messageChannelStyle = lipgloss.NewStyle().
+
-				Border(lipgloss.ThickBorder(), false, false, false, true).
+	errorLabel = errorStyle.Render("ERROR: ")
-				BorderForeground(lipgloss.Color("#757575")).
+	infoLabel  = infoStyle.Render("INFO: ")
-				PaddingLeft(1).
+
-				Margin(1, 0, 0, 0).
+	logChannelStyle = lipgloss.NewStyle().
-				Foreground(lipgloss.Color("#888888"))
+			Border(lipgloss.ThickBorder(), false, false, false, true).
+			BorderForeground(lipgloss.Color("#757575")).
+			PaddingLeft(1).
+			Margin(1, 0, 0, 0).
+			Foreground(lipgloss.Color("#888888"))
 )
 
+// renderRuntimeLog builds a single styled log line for the TUI log box.
+func renderRuntimeLog(log runtimeLog) string {
+	label := errorLabel
+	if log.level == runtimeLogLevelInfo {
+		label = infoLabel
+	}
+	return "[" + log.timestamp.Format("15:04:05") + "] " + label + log.text
+}
+
+// renderLogBox renders the styled log box, or "" when there are no lines.
+func renderLogBox(logs []string) string {
+	var b strings.Builder
+	for i, line := range logs {
+		if len(line) > 0 {
+			b.WriteString(line)
+			if i < len(logs)-1 {
+				b.WriteString("\n")
+			}
+		}
+	}
+	if b.Len() == 0 {
+		return ""
+	}
+	return logChannelStyle.Render(b.String())
+}
+
+func helpLine(cancelling bool) string {
+	if cancelling {
+		return helpStyle.Render("Stopping... (Ctrl+C again to force)")
+	}
+	return helpStyle.Render("Press Ctrl+C to quit")
+}
+
 type progressModel struct {
 	progress   progress.Model
 	startTime  time.Time
-	messages   []string
+	logs       []string
 	counter    *atomic.Uint64
-	current    uint64
 	maxValue   uint64
+	showBar    bool
 	ctx        context.Context //nolint:containedctx
 	stop       func()
 	cancelling bool
@@ -59,19 +96,8 @@ func (m progressModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		}
 		return m, nil
 
-	case runtimeMessage:
+	case runtimeLog:
-		var msgBuilder strings.Builder
+		m.logs = append(m.logs[1:], renderRuntimeLog(msg))
-		msgBuilder.WriteString("[")
-		msgBuilder.WriteString(msg.timestamp.Format("15:04:05"))
-		msgBuilder.WriteString("] ")
-		switch msg.level {
-		case runtimeMessageLevelError:
-			msgBuilder.WriteString(errorStyle.Render("ERROR: "))
-		case runtimeMessageLevelWarning:
-			msgBuilder.WriteString(warningStyle.Render("WARNING: "))
-		}
-		msgBuilder.WriteString(msg.text)
-		m.messages = append(m.messages[1:], msgBuilder.String())
 		if m.ctx.Err() != nil {
 			return m, tea.Quit
 		}
@@ -92,38 +118,27 @@ func (m progressModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 }
 
 func (m progressModel) View() string {
-	var messagesBuilder strings.Builder
+	var b strings.Builder
-	for i, msg := range m.messages {
+	if box := renderLogBox(m.logs); box != "" {
-		if len(msg) > 0 {
+		b.WriteString(box)
-			messagesBuilder.WriteString(msg)
+		b.WriteString("\n")
-			if i < len(m.messages)-1 {
-				messagesBuilder.WriteString("\n")
-			}
-		}
 	}
 
-	var finalBuilder strings.Builder
+	if m.showBar {
-	if messagesBuilder.Len() > 0 {
+		current := m.counter.Load()
-		finalBuilder.WriteString(messageChannelStyle.Render(messagesBuilder.String()))
+		b.WriteString("\n ")
-		finalBuilder.WriteString("\n")
+		b.WriteString(strconv.FormatUint(current, 10))
+		b.WriteString("/")
+		b.WriteString(strconv.FormatUint(m.maxValue, 10))
+		b.WriteString(" - ")
+		b.WriteString(time.Since(m.startTime).Round(time.Second / 10).String())
+		b.WriteString("\n ")
+		b.WriteString(m.progress.ViewAs(float64(current) / float64(m.maxValue)))
 	}
 
-	m.current = m.counter.Load()
+	b.WriteString("\n\n  ")
-	finalBuilder.WriteString("\n ")
+	b.WriteString(helpLine(m.cancelling))
-	finalBuilder.WriteString(strconv.FormatUint(m.current, 10))
+	return b.String()
-	finalBuilder.WriteString("/")
-	finalBuilder.WriteString(strconv.FormatUint(m.maxValue, 10))
-	finalBuilder.WriteString(" - ")
-	finalBuilder.WriteString(time.Since(m.startTime).Round(time.Second / 10).String())
-	finalBuilder.WriteString("\n ")
-	finalBuilder.WriteString(m.progress.ViewAs(float64(m.current) / float64(m.maxValue)))
-	finalBuilder.WriteString("\n\n  ")
-	if m.cancelling {
-		finalBuilder.WriteString(helpStyle.Render("Stopping... (Ctrl+C again to force)"))
-	} else {
-		finalBuilder.WriteString(helpStyle.Render("Press Ctrl+C to quit"))
-	}
-	return finalBuilder.String()
 }
 
 func progressTickCmd() tea.Cmd {
@@ -138,7 +153,8 @@ type infiniteProgressModel struct {
 	spinner    spinner.Model
 	startTime  time.Time
 	counter    *atomic.Uint64
-	messages   []string
+	logs       []string
+	showBar    bool
 	ctx        context.Context //nolint:containedctx
 	quit       bool
 	stop       func()
@@ -158,19 +174,8 @@ func (m infiniteProgressModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		}
 		return m, nil
 
-	case runtimeMessage:
+	case runtimeLog:
-		var msgBuilder strings.Builder
+		m.logs = append(m.logs[1:], renderRuntimeLog(msg))
-		msgBuilder.WriteString("[")
-		msgBuilder.WriteString(msg.timestamp.Format("15:04:05"))
-		msgBuilder.WriteString("] ")
-		switch msg.level {
-		case runtimeMessageLevelError:
-			msgBuilder.WriteString(errorStyle.Render("ERROR: "))
-		case runtimeMessageLevelWarning:
-			msgBuilder.WriteString(warningStyle.Render("WARNING: "))
-		}
-		msgBuilder.WriteString(msg.text)
-		m.messages = append(m.messages[1:], msgBuilder.String())
 		if m.ctx.Err() != nil {
 			m.quit = true
 			return m, tea.Quit
@@ -189,64 +194,60 @@ func (m infiniteProgressModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 }
 
 func (m infiniteProgressModel) View() string {
-	var messagesBuilder strings.Builder
+	var b strings.Builder
-	for i, msg := range m.messages {
+	if box := renderLogBox(m.logs); box != "" {
-		if len(msg) > 0 {
+		b.WriteString(box)
-			messagesBuilder.WriteString(msg)
+		b.WriteString("\n")
-			if i < len(m.messages)-1 {
-				messagesBuilder.WriteString("\n")
-			}
-		}
 	}
 
-	var finalBuilder strings.Builder
+	// Without a spinner, the view is just the log box (plus help until quit).
-	if messagesBuilder.Len() > 0 {
+	if !m.showBar {
-		finalBuilder.WriteString(messageChannelStyle.Render(messagesBuilder.String()))
+		if !m.quit {
-		finalBuilder.WriteString("\n")
+			b.WriteString("\n\n  ")
+			b.WriteString(helpLine(m.cancelling))
+		}
+		return b.String()
 	}
 
 	if m.quit {
-		finalBuilder.WriteString("\n  ")
+		b.WriteString("\n  ")
-		finalBuilder.WriteString(strconv.FormatUint(m.counter.Load(), 10))
+		b.WriteString(strconv.FormatUint(m.counter.Load(), 10))
-		finalBuilder.WriteString("  ")
+		b.WriteString("  ")
-		finalBuilder.WriteString(infiniteProgressStyle.Render("∙∙∙∙∙"))
+		b.WriteString(infiniteProgressStyle.Render("∙∙∙∙∙"))
-		finalBuilder.WriteString("  ")
+		b.WriteString("  ")
-		finalBuilder.WriteString(time.Since(m.startTime).Round(time.Second / 10).String())
+		b.WriteString(time.Since(m.startTime).Round(time.Second / 10).String())
-		finalBuilder.WriteString("\n\n")
+		b.WriteString("\n\n")
 	} else {
-		finalBuilder.WriteString("\n  ")
+		b.WriteString("\n  ")
-		finalBuilder.WriteString(strconv.FormatUint(m.counter.Load(), 10))
+		b.WriteString(strconv.FormatUint(m.counter.Load(), 10))
-		finalBuilder.WriteString("  ")
+		b.WriteString("  ")
-		finalBuilder.WriteString(m.spinner.View())
+		b.WriteString(m.spinner.View())
-		finalBuilder.WriteString("  ")
+		b.WriteString("  ")
-		finalBuilder.WriteString(time.Since(m.startTime).Round(time.Second / 10).String())
+		b.WriteString(time.Since(m.startTime).Round(time.Second / 10).String())
-		finalBuilder.WriteString("\n\n  ")
+		b.WriteString("\n\n  ")
-		if m.cancelling {
+		b.WriteString(helpLine(m.cancelling))
-			finalBuilder.WriteString(helpStyle.Render("Stopping... (Ctrl+C again to force)"))
-		} else {
-			finalBuilder.WriteString(helpStyle.Render("Press Ctrl+C to quit"))
-		}
 	}
-	return finalBuilder.String()
+	return b.String()
 }
 
-func (q sarin) streamProgress(
+func (s sarin) streamProgress(
 	ctx context.Context,
 	stopCtrl *StopController,
 	done chan<- struct{},
 	total uint64,
 	counter *atomic.Uint64,
-	messageChannel <-chan runtimeMessage,
+	logChannel <-chan runtimeLog,
+	showBar bool,
 ) {
 	var program *tea.Program
 	if total > 0 {
 		model := progressModel{
 			progress:  progress.New(progress.WithGradient("#151594", "#00D4FF")),
 			startTime: time.Now(),
-			messages:  make([]string, 8),
+			logs:      make([]string, 8),
 			counter:   counter,
-			current:   0,
 			maxValue:  total,
+			showBar:   showBar,
 			ctx:       ctx,
 			stop:      stopCtrl.Stop,
 		}
@@ -274,7 +275,8 @@ func (q sarin) streamProgress(
 			),
 			startTime: time.Now(),
 			counter:   counter,
-			messages:  make([]string, 8),
+			logs:      make([]string, 8),
+			showBar:   showBar,
 			ctx:       ctx,
 			stop:      stopCtrl.Stop,
 			quit:      false,
@@ -287,7 +289,7 @@ func (q sarin) streamProgress(
 	defer stopCtrl.AttachProgram(nil)
 
 	go func() {
-		for msg := range messageChannel {
+		for msg := range logChannel {
 			program.Send(msg)
 		}
 	}()

internal/sarin/worker.go

@@ -29,11 +29,12 @@ func statusCodeToString(code int) string {
 	return strconv.Itoa(code)
 }
 
-func (q sarin) Worker(
+func (s sarin) Worker(
 	jobs <-chan struct{},
 	hostClientGenerator HostClientGenerator,
 	counter *atomic.Uint64,
-	sendMessage messageSender,
+	sendLog runtimeLogger,
+	sendRespLog respLogger,
 ) {
 	req := fasthttp.AcquireRequest()
 	resp := fasthttp.AcquireResponse()
@@ -43,9 +44,9 @@ func (q sarin) Worker(
 	// Create script transformer for this worker (engines are not thread-safe)
 	// Scripts are pre-validated in NewSarin, so this should not fail
 	var scriptTransformer *script.Transformer
-	if !q.scriptChain.IsEmpty() {
+	if !s.scriptChain.IsEmpty() {
 		var err error
-		scriptTransformer, err = q.scriptChain.NewTransformer()
+		scriptTransformer, err = s.scriptChain.NewTransformer()
 		if err != nil {
 			panic(err)
 		}
@@ -53,79 +54,84 @@ func (q sarin) Worker(
 	}
 
 	requestGenerator, isDynamic := NewRequestGenerator(
-		q.methods, q.requestURL, q.params, q.headers, q.cookies, q.bodies, q.values, q.fileCache, scriptTransformer,
+		s.methods, s.requestURL, s.params, s.headers, s.cookies, s.bodies, s.values, s.fileCache, scriptTransformer,
 	)
 
-	if q.dryRun {
+	if s.dryRun {
 		switch {
-		case q.collectStats && isDynamic:
+		case s.collectStats && isDynamic:
-			q.workerDryRunStatsWithDynamic(jobs, req, requestGenerator, counter, sendMessage)
+			s.workerDryRunStatsWithDynamic(jobs, req, requestGenerator, counter, sendLog)
-		case q.collectStats && !isDynamic:
+		case s.collectStats && !isDynamic:
-			q.workerDryRunStatsWithStatic(jobs, req, requestGenerator, counter, sendMessage)
+			s.workerDryRunStatsWithStatic(jobs, req, requestGenerator, counter, sendLog)
-		case !q.collectStats && isDynamic:
+		case !s.collectStats && isDynamic:
-			q.workerDryRunNoStatsWithDynamic(jobs, req, requestGenerator, counter, sendMessage)
+			s.workerDryRunNoStatsWithDynamic(jobs, req, requestGenerator, counter, sendLog)
 		default:
-			q.workerDryRunNoStatsWithStatic(jobs, req, requestGenerator, counter, sendMessage)
+			s.workerDryRunNoStatsWithStatic(jobs, req, requestGenerator, counter, sendLog)
 		}
 	} else {
 		switch {
-		case q.collectStats && isDynamic:
+		case s.collectStats && isDynamic:
-			q.workerStatsWithDynamic(jobs, req, resp, requestGenerator, hostClientGenerator, counter, sendMessage)
+			s.workerStatsWithDynamic(jobs, req, resp, requestGenerator, hostClientGenerator, counter, sendLog, sendRespLog)
-		case q.collectStats && !isDynamic:
+		case s.collectStats && !isDynamic:
-			q.workerStatsWithStatic(jobs, req, resp, requestGenerator, hostClientGenerator, counter, sendMessage)
+			s.workerStatsWithStatic(jobs, req, resp, requestGenerator, hostClientGenerator, counter, sendLog, sendRespLog)
-		case !q.collectStats && isDynamic:
+		case !s.collectStats && isDynamic:
-			q.workerNoStatsWithDynamic(jobs, req, resp, requestGenerator, hostClientGenerator, counter, sendMessage)
+			s.workerNoStatsWithDynamic(jobs, req, resp, requestGenerator, hostClientGenerator, counter, sendLog, sendRespLog)
 		default:
-			q.workerNoStatsWithStatic(jobs, req, resp, requestGenerator, hostClientGenerator, counter, sendMessage)
+			s.workerNoStatsWithStatic(jobs, req, resp, requestGenerator, hostClientGenerator, counter, sendLog, sendRespLog)
 		}
 	}
 }
 
-func (q sarin) workerStatsWithDynamic(
+func (s sarin) workerStatsWithDynamic(
 	jobs <-chan struct{},
 	req *fasthttp.Request,
 	resp *fasthttp.Response,
 	requestGenerator RequestGenerator,
 	hostClientGenerator HostClientGenerator,
 	counter *atomic.Uint64,
-	sendMessage messageSender,
+	sendLog runtimeLogger,
+	sendRespLog respLogger,
 ) {
 	for range jobs {
 		req.Reset()
 		resp.Reset()
 
 		if err := requestGenerator(req); err != nil {
-			q.responses.Add(err.Error(), 0)
+			s.responses.Add(err.Error(), 0)
-			sendMessage(runtimeMessageLevelError, err.Error())
+			sendLog(runtimeLogLevelError, err.Error())
 			counter.Add(1)
 			continue
 		}
 
 		startTime := time.Now()
-		err := hostClientGenerator().DoTimeout(req, resp, q.timeout)
+		err := hostClientGenerator().DoTimeout(req, resp, s.timeout)
+		respDuration := time.Since(startTime)
+
 		if err != nil {
-			q.responses.Add(err.Error(), time.Since(startTime))
+			s.responses.Add(err.Error(), respDuration)
 		} else {
-			q.responses.Add(statusCodeToString(resp.StatusCode()), time.Since(startTime))
+			s.responses.Add(statusCodeToString(resp.StatusCode()), respDuration)
+			sendRespLog(respDuration, resp)
 		}
 		counter.Add(1)
 	}
 }
 
-func (q sarin) workerStatsWithStatic(
+func (s sarin) workerStatsWithStatic(
 	jobs <-chan struct{},
 	req *fasthttp.Request,
 	resp *fasthttp.Response,
 	requestGenerator RequestGenerator,
 	hostClientGenerator HostClientGenerator,
 	counter *atomic.Uint64,
-	sendMessage messageSender,
+	sendLog runtimeLogger,
+	sendRespLog respLogger,
 ) {
 	if err := requestGenerator(req); err != nil {
 		// Static request generation failed - record all jobs as errors
 		for range jobs {
-			q.responses.Add(err.Error(), 0)
+			s.responses.Add(err.Error(), 0)
-			sendMessage(runtimeMessageLevelError, err.Error())
+			sendLog(runtimeLogLevelError, err.Error())
 			counter.Add(1)
 		}
 		return
@@ -135,49 +141,57 @@ func (q sarin) workerStatsWithStatic(
 		resp.Reset()
 
 		startTime := time.Now()
-		err := hostClientGenerator().DoTimeout(req, resp, q.timeout)
+		err := hostClientGenerator().DoTimeout(req, resp, s.timeout)
+		respDuration := time.Since(startTime)
 		if err != nil {
-			q.responses.Add(err.Error(), time.Since(startTime))
+			s.responses.Add(err.Error(), respDuration)
 		} else {
-			q.responses.Add(statusCodeToString(resp.StatusCode()), time.Since(startTime))
+			s.responses.Add(statusCodeToString(resp.StatusCode()), respDuration)
+			sendRespLog(respDuration, resp)
 		}
 		counter.Add(1)
 	}
 }
 
-func (q sarin) workerNoStatsWithDynamic(
+func (s sarin) workerNoStatsWithDynamic(
 	jobs <-chan struct{},
 	req *fasthttp.Request,
 	resp *fasthttp.Response,
 	requestGenerator RequestGenerator,
 	hostClientGenerator HostClientGenerator,
 	counter *atomic.Uint64,
-	sendMessage messageSender,
+	sendLog runtimeLogger,
+	sendRespLog respLogger,
 ) {
 	for range jobs {
 		req.Reset()
 		resp.Reset()
 		if err := requestGenerator(req); err != nil {
-			sendMessage(runtimeMessageLevelError, err.Error())
+			sendLog(runtimeLogLevelError, err.Error())
 			counter.Add(1)
 			continue
 		}
-		_ = hostClientGenerator().DoTimeout(req, resp, q.timeout)
+		startTime := time.Now()
+		err := hostClientGenerator().DoTimeout(req, resp, s.timeout)
+		if err == nil {
+			sendRespLog(time.Since(startTime), resp)
+		}
 		counter.Add(1)
 	}
 }
 
-func (q sarin) workerNoStatsWithStatic(
+func (s sarin) workerNoStatsWithStatic(
 	jobs <-chan struct{},
 	req *fasthttp.Request,
 	resp *fasthttp.Response,
 	requestGenerator RequestGenerator,
 	hostClientGenerator HostClientGenerator,
 	counter *atomic.Uint64,
-	sendMessage messageSender,
+	sendLog runtimeLogger,
+	sendRespLog respLogger,
 ) {
 	if err := requestGenerator(req); err != nil {
-		sendMessage(runtimeMessageLevelError, err.Error())
+		sendLog(runtimeLogLevelError, err.Error())
 
 		// Static request generation failed - just count the jobs without sending
 		for range jobs {
@@ -188,80 +202,84 @@ func (q sarin) workerNoStatsWithStatic(
 
 	for range jobs {
 		resp.Reset()
-		_ = hostClientGenerator().DoTimeout(req, resp, q.timeout)
+		startTime := time.Now()
+		err := hostClientGenerator().DoTimeout(req, resp, s.timeout)
+		if err == nil {
+			sendRespLog(time.Since(startTime), resp)
+		}
 		counter.Add(1)
 	}
 }
 
-func (q sarin) workerDryRunStatsWithDynamic(
+func (s sarin) workerDryRunStatsWithDynamic(
 	jobs <-chan struct{},
 	req *fasthttp.Request,
 	requestGenerator RequestGenerator,
 	counter *atomic.Uint64,
-	sendMessage messageSender,
+	sendLog runtimeLogger,
 ) {
 	for range jobs {
 		req.Reset()
 		startTime := time.Now()
 		if err := requestGenerator(req); err != nil {
-			q.responses.Add(err.Error(), time.Since(startTime))
+			s.responses.Add(err.Error(), time.Since(startTime))
-			sendMessage(runtimeMessageLevelError, err.Error())
+			sendLog(runtimeLogLevelError, err.Error())
 			counter.Add(1)
 			continue
 		}
-		q.responses.Add(dryRunResponseKey, time.Since(startTime))
+		s.responses.Add(dryRunResponseKey, time.Since(startTime))
 		counter.Add(1)
 	}
 }
 
-func (q sarin) workerDryRunStatsWithStatic(
+func (s sarin) workerDryRunStatsWithStatic(
 	jobs <-chan struct{},
 	req *fasthttp.Request,
 	requestGenerator RequestGenerator,
 	counter *atomic.Uint64,
-	sendMessage messageSender,
+	sendLog runtimeLogger,
 ) {
 	if err := requestGenerator(req); err != nil {
 		// Static request generation failed - record all jobs as errors
 		for range jobs {
-			q.responses.Add(err.Error(), 0)
+			s.responses.Add(err.Error(), 0)
-			sendMessage(runtimeMessageLevelError, err.Error())
+			sendLog(runtimeLogLevelError, err.Error())
 			counter.Add(1)
 		}
 		return
 	}
 
 	for range jobs {
-		q.responses.Add(dryRunResponseKey, 0)
+		s.responses.Add(dryRunResponseKey, 0)
 		counter.Add(1)
 	}
 }
 
-func (q sarin) workerDryRunNoStatsWithDynamic(
+func (s sarin) workerDryRunNoStatsWithDynamic(
 	jobs <-chan struct{},
 	req *fasthttp.Request,
 	requestGenerator RequestGenerator,
 	counter *atomic.Uint64,
-	sendMessage messageSender,
+	sendLog runtimeLogger,
 ) {
 	for range jobs {
 		req.Reset()
 		if err := requestGenerator(req); err != nil {
-			sendMessage(runtimeMessageLevelError, err.Error())
+			sendLog(runtimeLogLevelError, err.Error())
 		}
 		counter.Add(1)
 	}
 }
 
-func (q sarin) workerDryRunNoStatsWithStatic(
+func (s sarin) workerDryRunNoStatsWithStatic(
 	jobs <-chan struct{},
 	req *fasthttp.Request,
 	requestGenerator RequestGenerator,
 	counter *atomic.Uint64,
-	sendMessage messageSender,
+	sendLog runtimeLogger,
 ) {
 	if err := requestGenerator(req); err != nil {
-		sendMessage(runtimeMessageLevelError, err.Error())
+		sendLog(runtimeLogLevelError, err.Error())
 	}
 
 	for range jobs {

nix/package.nix

@@ -0,0 +1,44 @@
+{ lib
+, buildGoModule
+, go_1_26
+, rev ? "unknown"
+, buildDate ? "unknown"
+}:
+
+(buildGoModule.override { go = go_1_26; }) (finalAttrs: {
+  pname = "sarin";
+  version = "1.4.0"; # bump per release
+
+  src = lib.cleanSource ../.;
+
+  vendorHash = "sha256-/r2mioVoMbrboumF0sjHhharkGImQAShmiOQtdS5DaE=";
+
+  subPackages = [ "cmd/cli" ];
+
+  env.CGO_ENABLED = 0; # fully static binary
+
+  ldflags = [
+    "-s"
+    "-w"
+    "-X=go.aykhans.me/sarin/internal/version.Version=v${finalAttrs.version}"
+    "-X=go.aykhans.me/sarin/internal/version.GitCommit=${rev}"
+    "-X=go.aykhans.me/sarin/internal/version.BuildDate=${buildDate}"
+  ];
+
+  preBuild = ''
+    ldflags+=("-X 'go.aykhans.me/sarin/internal/version.GoVersion=$(go version)'")
+  '';
+
+  # cmd/cli produces a binary named "cli"; rename it to "sarin".
+  postInstall = ''
+    mv $out/bin/cli $out/bin/sarin
+  '';
+
+  meta = {
+    description = "High-performance HTTP load testing tool built with Go and fasthttp";
+    homepage = "https://github.com/aykhans/sarin";
+    license = lib.licenses.mit;
+    mainProgram = "sarin";
+    maintainers = [ ];
+  };
+})