mehdi.cz https://www.mehdi.cz/blog Engineering work by Mehdi Akiki across startup products, financial systems, distributed infrastructure, and open-source systems including Rust, Deno, and rust-analyzer. en-us hello@mehdi.cz (Mehdi Akiki) hello@mehdi.cz (Mehdi Akiki) Tue, 16 Sep 2025 00:00:00 GMT https://www.mehdi.cz/blog/bash-arithmetic-eval Today I Learnt: Arithmetic evaluation https://www.mehdi.cz/blog/bash-arithmetic-eval Perform arithmetic inside bash scripts with $(( )) or let. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-change-directory Change directory quickly with cd https://www.mehdi.cz/blog/bash-change-directory cd navigates the working directory; use -, ~ and pushd/popd for convenience. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-chmod Change permissions with chmod https://www.mehdi.cz/blog/bash-chmod Set file permissions using chmod; octal and symbolic modes available. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-chown Today I Learnt: Change file owner with chown https://www.mehdi.cz/blog/bash-chown Change owner and group of a file. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-clear-screen Clear the terminal https://www.mehdi.cz/blog/bash-clear-screen Clear the terminal with clear or control-L, and reset a terminal that is in a bad state. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-cmp Today I Learnt: Compare files with cmp https://www.mehdi.cz/blog/bash-cmp Use cmp to compare two files byte-by-byte. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-coproc Coprocess communication with coproc https://www.mehdi.cz/blog/bash-coproc Use coproc to run a process and communicate with it via file descriptors. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-copy-file Today I Learnt: Copy files with cp https://www.mehdi.cz/blog/bash-copy-file Use cp to copy files and directories. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-create-empty-file Today I Learnt: Create an empty file with touch https://www.mehdi.cz/blog/bash-create-empty-file Create or update file timestamps with touch. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-curl Today I Learnt: Fetch a URL with curl https://www.mehdi.cz/blog/bash-curl Use curl to download or interact with HTTP endpoints. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-df Check disk free space with df https://www.mehdi.cz/blog/bash-df Use df to show disk free space; -h shows human-readable sizes. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-dirname Today I Learnt: Extract dirname from a path https://www.mehdi.cz/blog/bash-dirname Use dirname to get the directory component of a path. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-du Check disk usage with du https://www.mehdi.cz/blog/bash-du du reports directory and file sizes; use -sh for human-readable summaries. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-env Today I Learnt: Print environment variables https://www.mehdi.cz/blog/bash-env Show environment variables and inspect PATH. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-envsubst Substitute environment variables in templates with envsubst https://www.mehdi.cz/blog/bash-envsubst Use envsubst to replace $VAR placeholders in templates safely. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-export-variable Export environment variables https://www.mehdi.cz/blog/bash-export-variable export makes variables available to child processes; assign then export or do both on one line. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-find-files Today I Learnt: Find files with find https://www.mehdi.cz/blog/bash-find-files Search for files by name, type, size, and more using find. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-flock Today I Learnt: Use flock for atomic file locking https://www.mehdi.cz/blog/bash-flock Use flock to prevent concurrent script runs from clobbering files. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-free-memory Today I Learnt: Check memory with free https://www.mehdi.cz/blog/bash-free-memory Use free -h to inspect system memory usage. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-grep Search text quickly with grep https://www.mehdi.cz/blog/bash-grep Use grep for pattern search; -R to recurse, -n for line numbers, -i for ignore-case. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-head Show first lines with head https://www.mehdi.cz/blog/bash-head head prints the first N lines of a file; combine with tail or sed for ranges. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-here-string Here-strings (<<<) https://www.mehdi.cz/blog/bash-here-string Here-strings (`<<<`) feed a short string as stdin to a command. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-history Today I Learnt: Show command history with history https://www.mehdi.cz/blog/bash-history List recent shell commands. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-list-files Today I Learnt: List files with ls https://www.mehdi.cz/blog/bash-list-files Quick: list files including hidden and permissions. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-make-directory Create directories with mkdir https://www.mehdi.cz/blog/bash-make-directory Use mkdir -p to create nested directories safely from scripts. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-mkfifo Today I Learnt: Create named pipes with mkfifo https://www.mehdi.cz/blog/bash-mkfifo Use FIFOs to connect unrelated processes. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-move-file Today I Learnt: Move or rename files with mv https://www.mehdi.cz/blog/bash-move-file Move or rename files using mv. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-nice-renice Today I Learnt: Change process priority with nice and renice https://www.mehdi.cz/blog/bash-nice-renice Start a process with lower priority using nice. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-print-working-directory Today I Learnt: Print working directory with pwd https://www.mehdi.cz/blog/bash-print-working-directory Show current directory. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-printf Formatted output with printf https://www.mehdi.cz/blog/bash-printf Use printf for predictable, formatted output instead of echo. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-process-substitution Today I Learnt: Process substitution to treat commands like files https://www.mehdi.cz/blog/bash-process-substitution Use <(...) or >(...) to pass command output or input as a filename. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-read-variable Today I Learnt: Read user input in bash https://www.mehdi.cz/blog/bash-read-variable Prompt and read input into a variable with read. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-remove-file Remove a file with rm https://www.mehdi.cz/blog/bash-remove-file Use rm to remove files; consider safer alternatives interactively. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-reverse-search Reverse-search history https://www.mehdi.cz/blog/bash-reverse-search Use Ctrl+R to reverse-search your shell history interactively. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-rsync Sync with rsync https://www.mehdi.cz/blog/bash-rsync Use rsync for efficient, resumable synchronization; -a preserves attributes. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-scp Secure copy with scp https://www.mehdi.cz/blog/bash-scp Copy files over SSH using scp; consider rsync for complex syncs. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-sed Stream edit files with sed https://www.mehdi.cz/blog/bash-sed sed performs text transforms in a stream; safe inline edits with backups. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-select Today I Learnt: Interactive menus with select https://www.mehdi.cz/blog/bash-select Use select to build simple interactive menus in bash scripts. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtiladvanced https://www.mehdi.cz/blog/bash-shellcheck Lint shell scripts with shellcheck https://www.mehdi.cz/blog/bash-shellcheck Use shellcheck to find common shell scripting mistakes. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-sleep Today I Learnt: Pause with sleep https://www.mehdi.cz/blog/bash-sleep Sleep for a number of seconds. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-sort Sort and dedupe lines https://www.mehdi.cz/blog/bash-sort Sort lines and remove duplicates with sort and uniq; use -V for version-aware sorting. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-source-file Source a script into the current shell https://www.mehdi.cz/blog/bash-source-file Use `source` or `.` to run a script in the current shell so it can set variables/functions. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-ss Show listening sockets with ss https://www.mehdi.cz/blog/bash-ss ss inspects sockets; use -ltnp to list TCP listening ports with processes. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-subshell-grouping Subshells vs grouping https://www.mehdi.cz/blog/bash-subshell-grouping Use ( ) for subshells and { } for grouping commands in the current shell. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-tail Show last lines with tail https://www.mehdi.cz/blog/bash-tail Use tail to show last lines or follow a growing file. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-trap-signals Today I Learnt: Trap signals and cleanup https://www.mehdi.cz/blog/bash-trap-signals Use trap to run cleanup on EXIT or signals. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtiladvanced https://www.mehdi.cz/blog/bash-ulimit Control resources with ulimit https://www.mehdi.cz/blog/bash-ulimit Use ulimit to set resource limits for shells and processes. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-uname Today I Learnt: Show system info with uname https://www.mehdi.cz/blog/bash-uname Print kernel and OS information. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-version Show bash version https://www.mehdi.cz/blog/bash-version Display Bash version and release info. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-view-file Quickly view file contents https://www.mehdi.cz/blog/bash-view-file Use cat, less, more to view file contents; tail -f follows logs. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/bash-wget Download with wget https://www.mehdi.cz/blog/bash-wget Quick wget examples for downloading files and resuming partial downloads. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bashtil https://www.mehdi.cz/blog/case-study-projects Today I Learnt: Writing Project Case Studies That Sell https://www.mehdi.cz/blog/case-study-projects How to write concise project case studies that highlight impact and attract clients or recruiters. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) freelancecase-studyportfoliotil https://www.mehdi.cz/blog/getting-started-oso-nodejs Today I Learnt: Getting Started with Oso Authorization in Node.js https://www.mehdi.cz/blog/getting-started-oso-nodejs How to add policy-based authorization using Oso in a Node.js app with a minimal example. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) nodeauthosotil https://www.mehdi.cz/blog/github-profile-optimisation Today I Learnt: Optimizing Your GitHub Profile for Recruiters https://www.mehdi.cz/blog/github-profile-optimisation Make your GitHub profile and repos speak for you: README, pinned projects, issues, and contributions. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) githubopen-sourceportfoliotil https://www.mehdi.cz/blog/linkedin-personal-brand Today I Learnt: LinkedIn for Engineers — Practical Personal Branding https://www.mehdi.cz/blog/linkedin-personal-brand Small LinkedIn habits that make your profile and posts discoverable to recruiters and potential clients. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) linkedinpersonal-brandcareertil https://www.mehdi.cz/blog/open-source-for-recruiters Today I Learnt: Use Open Source to Get Noticed by Recruiters https://www.mehdi.cz/blog/open-source-for-recruiters How contributing to open source can surface you to recruiters and how to do it efficiently. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) open-sourcecareergithubtil https://www.mehdi.cz/blog/portfolio-structure Today I Learnt: Portfolio Structure That Gets Recruiter Attention https://www.mehdi.cz/blog/portfolio-structure A lean portfolio structure to showcase work, skills, and contact channels for recruiters and clients. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) portfoliopersonal-brandresumetil https://www.mehdi.cz/blog/show-impact-metrics Today I Learnt: Show Impact — Metrics That Recruiters and Clients Care About https://www.mehdi.cz/blog/show-impact-metrics Which metrics to show on your portfolio and how to present them so they communicate value quickly. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) metricsportfolioimpacttil https://www.mehdi.cz/blog/technical-blog-seo Today I Learnt: Technical Blogging for SEO and Visibility https://www.mehdi.cz/blog/technical-blog-seo Practical SEO tips for technical bloggers who want organic traffic and recruiter discovery. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) bloggingseotechnical-writingtil https://www.mehdi.cz/blog/technical-storytelling Today I Learnt: Technical Storytelling — Make Your Work Memorable https://www.mehdi.cz/blog/technical-storytelling How to tell the story of your technical work so recruiters and clients remember you. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) storytellingwritingportfoliotil https://www.mehdi.cz/blog/winning-proposals Today I Learnt: Write Winning Technical Proposals Quickly https://www.mehdi.cz/blog/winning-proposals A fast, repeatable proposal template to win freelance clients without over-engineering. Tue, 16 Sep 2025 00:00:00 GMT hello@mehdi.cz (Mehdi Akiki) freelanceproposalsprojectstil