Two audiences, one page
Your resume passes through an Applicant Tracking System that parses text into fields, then lands in front of a hiring manager or recruiter who spends six to fifteen seconds on the first screen. At Toolliyo we review hundreds of developer resumes for mock interviews and career coaching. The failures repeat: clever Canva layouts that ATS strips to gibberish, job descriptions copied without outcomes, and skills lists that read like a tag cloud with no proof.
This guide is practical: how to format, what to write, and how to tune for a .NET or full-stack role without sounding like you generated the whole document from a template.
ATS formatting rules that still matter in 2025
- Submit PDF only if the employer allows; when in doubt, DOCX with simple styles is safer for parsers.
- Single column layout—no tables for work history, no text boxes, no headers/footers for critical info.
- Standard section headings: Summary, Experience, Skills, Education—creative titles confuse parsers.
- Use standard fonts (Arial, Calibri, Helvetica) at 10–12 pt body.
- Contact info in body text, not only in an image or sidebar graphic.
- Avoid icons for email/phone; spell labels: Email, Phone, LinkedIn URL.
Length and structure
One page if under roughly eight years focused experience; two pages acceptable for senior/staff with consistent impact. Lead with a tight summary (three lines max) targeting the role: ".NET backend engineer with 6 years shipping B2B SaaS on Azure, EF Core, and high-volume SQL tuning." Not a life story.
Impact bullets beat task lists
Formula: Action + What + How + Result (metric when honest). Weak: "Responsible for API development." Strong: "Designed REST APIs in ASP.NET Core serving 12k RPM; cut p95 latency 40% by fixing EF N+1 queries and adding Redis cache with explicit TTL." If you lack metrics, use scope: "team of 4," "three markets," "zero-downtime migration."
Keywords without stuffing
Mirror language from the job description where truthful: ASP.NET Core, C#, EF Core, Azure, Docker, CI/CD, SQL Server, React if you used them. ATS matches tokens; humans smell keyword stuffing. Integrate terms into experience bullets, not a separate cloud of buzzwords unrelated to projects.
Skills section that helps interviews
Group: Languages, Frameworks, Data, Cloud/DevOps, Practices. Rate honestly—"Exposure" vs "Production" prevents interview traps. Do not list every technology you touched once in 2019 unless you can answer depth questions today.
Projects and portfolio for juniors and career changers
Two or three projects with live links or GitHub repos that build and run. Describe problem, your role, stack, and outcome. A deployed Toolliyo-style tutorial API beats ten unfinished repos.
What hiring managers delete quickly
- Unexplained gaps without one honest line optional in cover letter.
- "References available upon request"—wastes space.
- Photo, age, marital status—irrelevant in many markets and ATS-risky.
- Every job since 1998 with equal detail—trim early career to titles only.
- Objective paragraphs from 2005 templates.
Tailoring in thirty minutes
Keep a master resume with all bullets. For each application, reorder top three bullets per recent role to match posting priorities, adjust summary keywords, and verify title alignment (Software Engineer vs Developer is fine if consistent). Save as Role_Company.pdf for tracking.
Cover letter when worth it
Short: why this company, one proof point, availability. Not a duplicate resume. Many ATS attach it; make it parseable text.
LinkedIn alignment
Dates and titles should match resume. Recommendations and featured projects reinforce claims. Recruiters cross-check; inconsistencies trigger distrust.
Senior and staff signals
Emphasize ownership: migrations led, incidents resolved, standards introduced, mentoring, cross-team design. Staff resumes show multi-quarter initiatives and business outcomes, not only story points closed.
Common lies to avoid
Inflated titles, skills you cannot whiteboard, "led team" when you meant attended standups. Background checks and technical screens expose gaps; reputation in niche communities matters long-term.
Toolliyo career tools workflow
Draft resume, run through an ATS checker tool if available, book a mentor review for bullet rewrites, then mock interview using resume claims as the syllabus—every bullet should be defendable for ten minutes.
A software engineer resume wins when machines can parse it and humans see credible impact in seconds. Invest in bullets tied to measurable outcomes, honest keywords, and formatting boring enough for ATS—and compelling enough that a manager wants to call you.