A modern, minimal lightweight API testing tool

NitroHttp

NitroHttp is a desktop HTTP client for fast API testing.

It focuses on a clean UI and practical workflows:

• Send requests quickly (GET, POST, PUT, PATCH, DELETE)
• Build query parameters visually
• Inspect response body, status, time, size, headers, and cookies
• Persist recent requests (history) and reusable requests (collections)

Features

Request builder

• HTTP methods: GET, POST, PUT, PATCH, DELETE
• URL input with automatic query-string sync from key/value parameter rows
• JSON request body editor (AvaloniaEdit)

Response viewer

• Status code + reason phrase (e.g., 200 OK)
• Response count (object/array aware for JSON)
• Elapsed time (ms) and payload size (B, KB, MB)
• Response tabs:
  • Body (pretty-printed JSON when possible)
  • Headers
  • Cookies

Request persistence

• History stores up to 50 unique recent requests
• Collections lets you save named requests
• Data is stored as JSON on disk and restored at app startup

Tech stack

• .NET net10.0
• Avalonia 11.3.x
• AvaloniaEdit 11.3.x

Project structure

• Program.cs – desktop app entrypoint
• App.axaml, App.axaml.cs – application setup and theme wiring
• MainWindow.axaml – full UI layout
• MainWindow.axaml.cs – request execution, tab logic, persistence, response rendering
• Helpers/HttpStatusHelper.cs – status code text + status group helpers
• Helpers/FormatBytes.cs – human-readable response size formatting
• Helpers/RequestStore.cs – persisted model (History, Collections)
• scripts/publish-all.sh – multi-runtime publish helper
• scripts/package-deb.sh – Linux .deb packaging helper

Prerequisites

• .NET SDK that supports net10.0
  • Verify with: dotnet --info
• Linux/macOS/Windows desktop environment

For Debian packaging:

• dpkg-deb
• python3 + pip
• Pillow (PIL) (auto-installed by script if missing)

Run locally

dotnet restore
dotnet run

Build

dotnet build -c Release

Publish binaries

Scripted publish (Linux + Windows)

bash scripts/publish-all.sh

Outputs:

• publish/linux-x64/
• publish/win-x64/

Manual publish example

dotnet publish NitroHttp.csproj \
	-c Release \
	-r linux-x64 \
	--self-contained true \
	/p:PublishSingleFile=true \
	/p:IncludeNativeLibrariesForSelfExtract=true \
	/p:PublishTrimmed=false \
	-o publish/linux-x64

Package as Debian .deb

bash scripts/package-deb.sh 1.0.0

Output package:

• dist/nitrohttp_1.0.0_amd64.deb

Install:

sudo dpkg -i dist/nitrohttp_1.0.0_amd64.deb

Data storage

NitroHttp stores request history and collections in a JSON file:

• Path base: Environment.SpecialFolder.ApplicationData
• Relative file: NitroHttp/requests.json

On Linux this typically resolves to:

• ~/.config/NitroHttp/requests.json

Stored model:

• History[]
• Collections[]
• Each item includes Method, Url, Body, Timestamp, and optional CollectionName

Usage guide

1. Select method and enter URL.
2. Add query params from the Params tab (+ Add).
3. Add JSON body in Body tab for write methods.
4. Click NITRO to send.
5. Inspect response stats and switch between Body / Headers / Cookies tabs.
6. Save frequently used requests in Collections.

Current behavior and limitations

• Request body content type is JSON (application/json) for POST, PUT, PATCH.
• Query parameters are applied by rewriting the URL from the Params panel.
• Response headers and cookies are currently populated for GET flow.
• Headers and Auth request input panels are present in UI but not yet applied to outgoing requests.
• History deduplicates by (Method, Url, Body) and keeps newest first.

Troubleshooting

• Blank response or URL error: ensure URL is not empty and includes http:// or https://.
• JSON not formatted: response is likely not valid JSON; NitroHttp shows raw text.
• Packaging fails on Linux: verify dpkg-deb, python3, and pip are installed.

Roadmap ideas

• Apply custom request headers from the Headers tab
• Apply bearer/API-key auth from the Auth tab
• Export/import collections
• Save/copy response actions wiring
• Additional body types (form-data, x-www-form-urlencoded)